|[^lriJiJ| liril[rirgfiirLlffmJ|ririif f^ i 1 1 1 1 i i i i 1 i THE LIBRARIES COLUMBIA UNIVERSITY r5i General Library i 1 1 1 1 1 1 1 i 1 1 E] [inJj Juil|pjDl riJi'/fmJ[ iin]|?ijOf r^ \ DESCRIPTION or THE WESTERN ISLANDS OF SCOTLAND. VOL. I. LONDON : rniNTED UV J. MOVLS, CISKVILLE STlir.FT. DESCRIPTION THE WESTERN ISLANDS SCOTLAND, INCLUDING THE ISLE OF MAN COMPRISING AN ACCOUNT OF THEIR GEOLOGICAL STRUCTURE; REMARKS ON THEIR AGRICULTURE, SCENERY, AND ANTIQUITIES. BY JOHN MACCULLOCH, M. D. IN THREE VOLUMES. VOL. I. LONDON: PRINTED FOR ARCHIBALD CONSTABLE AND CO. EDINBURGH j AND HURST, ROBINSON, AND CO. CHEAPSIDE, LONDON. 1819. CONTENTS TO THE FIRST VOLUME. Page Introductory Remarks on the general Disposition of the Western Islands .••.. 1 Introductory Remarks on the Gneiss Islands 3 lona 5 Tirey 22 Coll 51 Barra 70 Vatersa. Sandera. Pabba. Muldonich. Mingala. Bernera* 84 Eriska. Fudia. Hellesa. Gia 87 South Uist 91 Benbecula 99 North Uist 118 Rona (West) 152 Harris • 154 Taransa. Scarpa. Scalpa. 168 Lewis • 171 The Flannan Isles 198 Sulisker. North Rona 204 Rona (East) 212 Concluding Remarks on the Gneiss Islands 216 vi CONTENTS. Page Introductory Remarks on the Trap Islands 235 Rasay 239 Flodda 259 Sky 262 Soa 420 Pabba. Guilleraon 422 Longa 424 Scalpa 426 The Shiant Isles 435 Canna 445 Sandy Isle 465 Rum 473 Egg 507 Muck 523 Inch Kenneth 527 Mull 530 Ulva. Gometra. Colonsa. Eorsa 581 The Treshinish Isles 585 PREFACE. The following book owes its existence to a collection of papers originally drawn up for the Geological Society. Circumstances, consisting chiefly in their accumulation, induced me to bring the whole into one general view, and to add that which was wanting to render the Work a connected geological account of all the Western islands. In carrying this design into execution, it became necessary to re-model the greater number of these detached essays ; on account of the numerous con- nexions existing among the several islands, and the frequent repetitions of similar facts which were discovered by thus approximating them under one collective point of view. Many omissions were thus unavoidably made ; so that, in a great number of cases, the descriptions of individual islands will appear superficial and imperfect, even where they were ori- ginally full. In a topographic view, it would have been desirable to have retained the whole of them entire ; but as the chief interest of such details is rather of a general than a local nature, that accuracy would scarcely have compensated for the tedious length and frequent repetitions which would have resulted from such a procedure. It will however be perceived, viii PREFACE. that the deficiency occurring in one, is supplied in some other island of analogous structure ; and it has every where been attempted, so to refer and arrange the several facts, as to enable the reader to supply for himself whatever may be wanting towards a minute account of each ; as far at least as they are known to myself. In thus approximating the islands of analogous structure, for the purpose of rescinding repetitions or superfluities, an attempt has also been made to unite them, as far as possible, into groups regulated by their natural affinities. Thus they mutually assist in explaining the structure of each other; that which is obscure in one, being elucidated by some other of the group ; while the interest of the whole is increased by the comparison. To aid the geological reader in deducing from them those general conclusions which are more interesting to him than a naked col- lection of topographic details, an article is subjoined to each division, in which it is attempted to bring the principal facts into one condensed point of view. By this it is hoped that his progress through the work will be facilitated, and that a small portion at least of that fatigue, which is always the result of a long continued statement of details, will be removed. As it is not however probable that the conclusions of the reader will always coincide with those of the writer, there is still abundant room left for his own reflec- tions. Lastly, in examining the general relations of the different individuals of each group, it has also been attempted to connect them with the adjoining main- land, wherever it appeared necessary to do so for their PREFACE. ix illustration ; avoiding, as far as possible, any en- croachment on such a description of it as can only be the result of future investigations. It is probable that some assistance will thus be afforded to those who may hereafter, with more industry or oppor- tunities, supersede the wish of the author to extend this survey to the Scottish continent. In approximating the several parts, it became very soon visible that the incessant repetition of mere geological details, would produce a book which would be repulsive to a general reader, and laborious in no common degree, even to a geo- logical one. To relieve this uniformity, as far as was possible consistently with the scale and design of the Work, a variety of matter, of a more mis- cellaneous and general nature, has therefore been introduced into the account of several of the islands, just as it happened to be found in the writer's journal. The more slender notices of this kind have naturally fallen into the form of notes; and it was no part of the plan to introduce a personal narrative into the description of a country so often visited by travellers. Those travellers have, with various powers and with different success, related much of that which might otherwise have fallen to the lot of the author to describe; but they have not related all, as no one of them has made such wide excursions. That which has already been described, has rarely been touched again, as it could not often have been done better: nor was it a part of this plan to write an universal work on a subject so extensive as the present ; including, as it does, matter so various, and so intimately connected with the ancient history and present State of the Highlands of Scotland. If any X PREFACE. apology for the scattered position and desultory style of these remarks is necessary, it can only be said that they are introduced just where they arose. To have arranged them in a systematic form, would have led the reader to expect more than was intended, and would have given an air of pretension which the writer is abundantly conscious he could not have justified by a corresponding execution. It must also be remembered that a work may be too long; and that it was necessary to economize the allotted space for that which was the leading object, namely, the geological history of the islands. If the warmth of Caledonian feelings on subjects which relate to Scotland has any where been offended, it would be a source of regret : the writer has himself carried into that country no small share of Caledonian affections, hereditary and acquired ; but he has attempted to view these questions with the eye of an unprejudiced " Sassanach." In the details of the Work, every island which appeared deserving of notice has been described, from North Rona to the Isle of Man. The ex- ceptions that will be found, consist chiefly of the numerous islets which lie on the shores of the Long island, connected principally with North Uist. They presented nothing to require any further notice than that which is given in the map, where their composition is indicated. Every islet, however small, wherever it offered any peculiarity requiring remark, has been introduced. If any apo- logy is deemed necessary for here including the Isle of Man, it must be recollected that it once formed a political part of the Western islands. With the assistance to be derived from the maps, it PREFACE. xi is hoped that the account of the geological topography will generally be found as complete as the present state of the geography of these islands permitted. To render such details rigidly correct, requires a degree of geographical accuracy which is not at present attainable, and an extended scale of engrav- ings which the necessary economy of the plan did not permit. As many of the papers which gave rise to this Work, were drawn up at different and distant periods, and with other views; and as some parts were un- avoidably written while the remainder was going through the press, incongruities and repetitions, and probably, contradictions also, will be discovered. On reviewing indeed many parts of it, after four years, I find much that might be altered and much that might be improved. But the fluctuations of opinion, or the increase of knowledge, to which every observer must be subject, are scarcely greater than those by which the science of geology is now almost daily affected. Had the Work been kept to the Horatian period, it would doubtless have required more altera- tions. Had it been written nine years hence, it might have been even more defective ; as the science might have still further outstripped the acquirements of the author. Whatever may happen in this respect, it is still hoped that the facts will prove useful. As far as they have been carefully investigated, they will assist others in laying the foundation of a more accurate and extended knowledge of this subject: even where these state- ments shall prove unfounded, they will stimulate future observers, in examining and controverting them, xii PREFACE. to elicit the truth where it has here been misrepre- sented or overlooked. In many instances that have come under review in the examination of these islands, it would have been desirable to have referred to corresponding appear- ances on the continent of Europe, or in other analogous situations ; as such comparisons must have materially increased the general interest of the facts here described. But those countries are unknown to me; and in attempting to compare my own ob- servations with those recorded by authors, I have been unable to satisfy myself respecting their corre- spondence ; partly from uncertainty as to the use of terms, partly from a doubt whether, in many cases, the observations in question were purely practical, and, occasionally, from the broad and abstract mode in which those statements are made, and the rapid and general manner in which the examinations appear to have been conducted. With respect to the observations of British geolo- gists, I have, for other reasons, rarely been able to derive advantage from them. These have been prin- cipally limited to the secondary country of England, while the present relate chiefly to the primary rocks. Further, as the light under which many of these facts have appeared to myself, has sometimes differed from that in which they have been viewed by others, comparisons of such a nature would have inevitably led to a species of controversial examination which it seemed desirable to avoid, and which would have prolonged the Work without much apparent utility. Where it was impossible to avoid such remarks with- PREFACE. xiii out leaving the subject in darkness, they have been introduced. I must not however terminate this part of the subject without noticing Professor Jameson's work on the same tract of country. I would willingly have shortened my own labour by being indebted to it, and am glad to bear testimony to the accuracy of his ac- count, as far as the facts have been described. The difference of the plan on which this survey was con- ducted, rendered it necessary to examine every thing, and deprived me of the assistance which I might otherwise have derived from that work ; which in- cludes, moreover, but a small portion of the territory which has here been investigated. If the following descriptions should sometimes appear unnecessarily minute, and therefore prolix, it must be recollected that a merely topographical account would contribute nothing towards geological science. That science remains yet to be created ; and the facts that are to be collected towards it, must be viewed in the manner which our present conjectures as to their eventual utility may suggest as prospectively most conducive towards that leading object. When geological analogies and relations shall become thoroughly understood, a work on mineral topography will be comparatively brief, and may admit of being superficial. It is moreover impos- sible, in the present state of the science, to foresee the utility of minute research, or the serious defi- ciencies which may hereafter be found to arise from the neglect of circumstances apparently trifling. The classical naturalists doubtless imagined that they had given descriptions by Avhich the objects of their investigations could be for ever recognised. Our xiv PREFACE. early mineralogists and geologists also, appear to have been satisfied with their own limited accounts of the subjects of their researches. Yet we are hardly able to refer with certainty to one object in the descriptions of the former; and the obser- vations of the latter scarcely enter at present as a constituent into the science. The recent light thrown on geology by the minute circumstances which attend tne junctions of different classes of rock and the passage of veins, are too well known to require to be pointed out among the latest im- provements in the mode of observation. It has also been imagined, that from thus mi- nutely detailing some of these appearances, the geological student, to whom practical investigations are yet unknown, may derive rules for his guidance, and, without the formality of instruction, receive hints that may tend to shorten his labour and direct his attention to those circumstances in the history of rocks which appear to be the most important and the most in need of illustration. I fear the reader will have reason to complain that he cannot here discover any traces of a general theory, nor sufficient references to past theories to guide his steps through the multitude of details. If he should also complain that disorder has been introduced into a system which possesses, at least, a respectable regularity, I can only say that the want of coincidence between the present facts and our systems, cannot be a greater cause of inconvenience to him than it was to myself The want of a theory to which the observed appearances could be recon- ciled, proved a constant source of difficulty, and of PREFACE. XV labour ; and the doubts which thence arose respecting their truth, were of a nature to demand frequent comparisons, and repeated examinations. Such as the facts are, I have however attempted, as far as the plan of the work permitted, to place them in such a light as to render them useful to those who may possess greater inclination or greater power to arrange them under some general theory. If they feel the same difficulties in this respect as myself, they will not be in haste. Wherever the observations disagree with received opinions, I can only trust that the references to the places where they were made, are so precisely detailed that any one may find the means either of verifying or of correcting them. If there are inconsistencies, it is to be hoped that they will be found to lie between the facts and previous opinions : they may often, perhaps, exist in the observations ; but they will not be found in Nature. To investigate well is the first duty of a naturalist, and to relate the truth is the duty of all; but every one imagines himself alone to be free of prejudices. There is much yet to be done by those who cultivate this science, but in pursuing his investigations, it is especially necessary for the geologist never to lose sight of the rule of Seneca ; " Nihil magis praestandum quam ne pecorum ritu sequamur antecedentium gregem, pergentes non quS, eundem est sed qua itur." OBSERVATIONS THE GEOLOGY OF THE WESTERN ISLES OF SCOTLAND. INTRODUCTORY REMARKS ON THE GENERAL DIS- POSITION OF THE WESTERN ISLANDS. For the purpose of rendering the physical description of these islands more intelligible in a topographic view, and more interesting to the geologist in a scientific one, I have divided them into five distinct groups. These are distinguished by the names of the Gneiss, the Trap, the Sandstone, the Schistose, and the Clyde islands*. The four first are associations strictly natural, since a com- munity of structure, with a considerable geographical con- nexion, pervades each group. The last is founded chiefly on geographical community of position in the islands it includes ; although, even in this, certain common characters will be found in a greater or less degree to predominate through the whole. By treatmg of them in this manner the relations which they bear to the continent of Scot- land will be the more readily understood ; while from the great length of line they occupy on the western coast, and the analogy of their structure and disposition to those of the continental strata, they will be found to illus- trate in a very considerable degree its geological history. It is impossible to cast our eyes on the map wdthout being struck by the general north-easterly tendency, not * To these have been added two distinct articles, which conld not he included in either division, VOL. I. B 2 INTRODUCTORY REMARKS. only of tlie western coast, but of the leading vallies and ridges of Scotland. An analogous disposition will be found to prevail in these islands ; and the variations, which occasionally amount to a few points on the con- tinental shore, will receive illustration from circum- stances that will come under review in giving the details of the individual islands. These bearings of the coast and of the ridges of hills, will be seen, in most cases, to follow the directions of the strata, as will be exemplified in Sky and in many other places ; although in a few, as in Bute for example, there is a want of this coincidence. I must here remark generally, that the imperfections of the Map form a source of occasional error and render it difficult to ascertain the general bearings, whether of the land or the strata; a defect which there is no immediate prospect of removing. Examples in illustration of this remark will occur in the course of the investigation. To what extent the description of these Islands may assist in laying a foundation for determining the general structure of the Highland district, is a question that involves con- siderations too numerous to admit of a definitive answer. We may expect, that in a certain degree similar rocks will be found on the prolonged bearings of those which have been ascertained ; and, as far as my observations have gone, such continuations can be traced over a space, at least sufficient to regulate considerably the plan of any geologist, who shall pursue the investigation of the neighbouring main land*. Causes, too well known to require mention, limit the assistance to be derived from this circumstance; yet, when the Islands shall have been described, it will be seen that a considerable step has been gained, and a point of departure fixed for the future examination of the Highland and motintainous division of Scotland. * While this work is passing through tlie press, I am in tlie act of verifying the truth of this conjecture, by an extensive examination of tlie western coast. Sept. 1818. GNEISS ISLANDS. GENERAL REMARKS. 3 INTRODUCTORY REMARKS on the GNEISS ISLANDS, The first group, in the order of examination that I have adopted, is that of the Gneiss Islands. The greatest body of this rock occupies the outer chain of the Western Isles, which is so nearly identical from one end to the other, as to admit of httle variety in description. The next portion, in point of dimension, forms the chain of Coll and Tirey ; while lona, separated from these by a wide channel, may almost be considered as independent. Rona, and the northern part of Rasay, present a tract equally independent, and far removed from all the others. The general bearings of these several divisions will be found to conform more or less accurately to the leading lines of the coasts of Scotland, as I have before remarked of the islands in general; subject, at the same time, to that deviation which has been already noticed. Yet it will be seen that I have been unable to determine the actual bearings of the strata in the outer chain, popularly known by the name of the Long Island. I do not, however, hold this to be a reason for assuming the non-existence of such a continuous bearing in its stratification, but .should rather consider the directions of the coast lines as sufficient indications of what I have been unable to prove from an examination of the strata. This deficiency may possibly have arisen from my own inattention; but it will at any rate prove, that the observations have not been biassed by theoretic views. I am rather inclined to attribute it to the contortion and displacement of the strata which the gneiss invariably presents wherever I have examined it, throughout the course of that extensive phain. Hence, it becomes impracticable to trace the 4 GNEISS ISLANDS.^ — GENERAL REMARKS. alignement of the limited portions, which alone are amenable to strict investigation; while it is equally im- possible to cast a more extensive view over the whole, from the interrupted nature of the ground, and the evanescence of the indications of bearing, when points, sufl&ciently distant to admit of their being comprehended on a large scale, are taken. The contemplation of Coll and Tirey, as well as of lona, may perhaps confirm this suspicion, and add weight to the opinion, that the forms of the coasts in the Long Island depend on the direction of the strata. In these islands it is often equally impossible to trace the bearings of the gneiss ; yet in certain places, where granite veins do not interfere, it will hereafter be seen that the beds are perfectly straight, and that' their bearings correspond with the position and leading outlines of the chain. The same circumstance is visible in lona, where the prevailing straightness of the beds enables us to compare them with the general form of the island. But this con- formity, if it be thought not sufficiently established by these arguments, or if it be considered worthy of further confirmation, must be left for the determination of future observers. I shall therefore proceed to describe the several islands in the order which appears most con- venient, reserving all general comparisons till each group has been described. This description will be found to comprise all the principal, and even some of the sub- sidiary islands : those only being omitted which partake of a common character, and present nothing but a repetition of the same appearances. ION A. — DESCRIPTION. lONA. The historical and antiquarian celebrity of this little island renders it an object of perpetual attraction to the numerous visitors who now annually frequent these regions, so lately almost unknown to any but the natives and those immediately connected with them. Being easy of access, and occupying but little of the time usually allotted to Staffa, the prime object of attraction, it is the resort of all who have, in defiance of the rude seas or still ruder rocks of Mull, ]3enetrated thus far, either in search of the picturesque or for the gratification of general curiosity. Added to this, the descriptions of Cordiner, Pennant, and others, with the remarks of Doctor Johnson, have made its history nearly as familiar as its name ; giving it, in fact, an importance to which it possesses no claims, either from the antiquity or extent, the beauty or curiosity, of its architectural remains. In any other situation, the remains of lona Vv^ould be con- signed to neglect and oblivion; but connected as they are with an age distinguished for the ferocity of its manners and its independence of regular government, standing a solitary monument of religion and literature, such as religion and literature then were, the mind im- perceptibly recurs to the time when this island was the " light of the western world," " a gem in the ocean ;" and is led to contemplate with veneration its silent and ruined structures. Even at a distance, the aspect of the Cathedral, insignificant as its dimensions are, produces a strong feeling of delight in him, who, long coasting the rugged and barren rocks of Mull, or buffetted by turbulent waves, beholds its tower first rising out of the deep ; giving to this desolate region an air of civiliza- tion, and recalling the consciousness of that human * See the Map of Mull. 6 lONA. DESCRIPTION. society, which, presenting elsewhere no visible traces, seems to have abandoned these rocky shores to the cor- morant and the seagull. This island is about three miles in length, and one in breadth, being placed nearly in a north-easterly direction. Its eastern coast is separated from Mull by a nar- row sound, which, although obstructed by a partial shoal, affords passage with a leading wind to large ships navigating these seas. The western side is beset with numerous small islands and rocks : many are also scattered about its northern and southern extremities, near the latter of which the green island of Soa stretches to sea at a considerable distance. The surface of lona is low, rising into numerous irre- gular elevations, which seldom exceed 100 feet. Its highest hill may be about 400, and is situated at the northern extremity of the island. The coast is, for the most part, indented by small rocky bays divided by similar promontories ; but at the north-western side it presents one large plain terminating in a flat shore of sand chiefly composed of broken shells. Another sandy and low plain to the east, contains the ancient remains and the modern village. This plain is but of small extent, and the soil, although arable, is of a light and sandy quahty, applicable almost only, and that by the assistance of sea weed, to the cultivation of barley and potatoes. A small quantity of lye is grown ; but oats, as in similar soils elsewhere, do not succeed. The upland is a checquered mixture of rocks and pasture, generally moorish, displaying, towards its northern end, a mere labyrinth of rocks, among which it is difficult to explore a way. A few ridges of corn are occasionally found in this upland where the soil is sandy; but it is chiefly pastured by black cattle ; which, together with kelp, grown on the shores, and fish, in the taking of which the in- habitants display an industry unusiial in this country, form the disposable produce of the island. The population amounts to 450, the rent to £.300 ; and the land is divided lONA. — AGRICULTURE. / into distinct crofts, in the manner now becoming generally prevalent. This division is but recent, lona, like most of the farms of the Western Islands, having been, till lately, held in run-rig, as it is called, and each farm annually divided by lot. No plan could well have been devised more effectual in preventing the good treatment, as well as the improvement of the soil; every man's interest being thus set in decided opposition to that of the collective farm, and of the landholder. But the practice is fast expiring, as well as the whole system of tacks and sub- tenantry, with which it was connected. An amelioration in the mode of culture will, to a certain extent, naturally follow : but- the consequent rehef to the population of these islands can only be temporary. The lapse of time will again, as it is speedily doing, generate a population as redundant as it was under a worse cultivation, and again produce the same poverty and miseiy; if, indeed, the state of these small tenants can be considered as any thing at present but a perpetual contest with poverty. A far different system must be adopted, before any per- manent amehoration in the condition of the people can be effected. The number of persons above mentioned corresponds to about ninety families ; five and a fraction constituting the average of a Highland family*. Thus three pounds, or thir- teen shiUings per individual, becomes the annual rent of a tenement of land, the house having no value : and this, with some fluctuation in different places, will be found to represent pretty nearly the average rent of an individual throughout these islands. But I shall hereafter give a more general account of these subjects, foreseeing that partial details would otherwise be inevitable, and that they would scarcely be intelligible to those to whom the * It is, perhaps, superfluous to say, that celibacy is nearly unknown^ in these islands. lONA. ANTIQUITIES. country is not practically known; however brief that account must, from the nature of this work, be made. Were I to omit all notice of the antiquities of this island, the blank might appear to result from negligence, or from a want of proper curiosity : yet the subject has been nearly exhausted by numerous writers, and scarcely admits of revival, even for the pui-pose of relieving the barrenness of that which forms the principal featui'e of these volumes. It is pleasing, in the meantime, to see the effect which these writings, and the increased diffusion of a regard for the arts, have produced, in exciting a decent attention to the preservation of monuments which may rather be considered as historical, than as works of art. They are no longer degraded to the purposes of stabhng for cattle, nor dilapidated for the erection of cottages for the in- habitants. It is difficult to conjecture whether there are any remains so ancient as the time of St. Columba. If there are any such, they are probably to be found among the monumental stones : and among the crowd of those which are mixed together, of all ages, and in different styles, of which many have also been removed and again re- placed for purposes of recent interment, it would be impossible to distinguish those of high antiquity, deficient as they probably are both in sculpture and inscriptions. To search for such remains among the buildings, appears useless ; since the state of society in these regions, in the middle of the sixth century when Columba landed, must have rendered the early settlers incapable of erecting pei-manent works in stone and lime ; the use of which was an improvement belonging to much later times. The original abbey, improperly so called, (since the introduction of monastic regimen was long pos- terior to the time of Colmiiba,) appears to have been lONA. — ANTIQUITIES. 9 built of wattles; a species of structure equally used in South Britain in the common dwellings, as in the earliest rehgious edifices after the introduction of Christianity, and recorded in the history of the foundation of Glastonbury : a practice from which some antiquaries, following the hints thrown out by Warburton, have attempted to deduce a visionary theory of the origin of Gothic architecture. An imaginary high antiquity has been assigned to the present buildings; no record of the real times of their erection having survived the decree of the Synod of Argyll, which overturned all that a mob of reformers was capable of destroying, and dispersed, together with the library of the monastery, (the object of regrets perhaps much misplaced,) all the writings which could have thrown light on the subject. It is futile to quote the testimony of Boethius, or of any early writer, in competition with the internal evidence derived from the buildings them- selves ; while Pennant, although aware of the fabulous nature of that testimony, has left the question unexamined, the history of our ecclesiastical architecture not having been an object of general attention at the time his account was written. If it were possible to draw a permanent and effectual distinction between the earliest specimens of this style of architecture and those which followed the Norman invasion, we should be perhaps justified in referring St. Oran's Chapel, which bears marks of the highest antiquity, to the Saxon age. The smallness of its scale, which is sixty feet by twenty, its general rudeness, and the per- petual repetition of the chevron moulding in the low circular arch that forms the doorway, assimilate it to those buildings in England which have been supposed prior to the eleventh century. But architects are too little satisfied with respect to Saxon buildings, to admit of such a decision : it can only be presumed from the poverty of the style and execution; circumstances which might easily have arisen from the poverty of the 10 lONA.-— ANTIQUITIES. monasteiy, and the peculiar remoteness of its situation. The tombs within, of which one is placed under a canopy of three pointed arches, offer no objection to such a distant origin, as these are all evidently posterior to the building itself. The Chapel of the Nunnery is, perhaps, the next in order of antiquity, the arches being also round, but without ornaments : and as the whole style of the building partakes of the general plan of the Norman churches before orna- ments came into use, and previous to any appearance of the pointed arch or of the other pecuharities Avhich were introduced at a later date, I should be inclined, from internal evidence, to place it beyond the twelfth century. The structure of St. Mary's Church, which was at the same time the Abbey Church and the Cathedral of the Diocese of the Isles, bespeaks a later origin, and can- not be referred to a date more distant than the early part of the thirteenth century, if it be even of an antiquity so high*. It is in the form of a cross, with a square tower at the intersection, but of small dimensions and executed in a manner which bespeaks both the limited means of the founders, and the inexpertness of the artists ; circumstances in general sufficiently visible in a great number of the ecclesiastical remains of Scotland. The length from east to west is about one hundred and twenty feet, and that of the transept about seventy. The tower is about seventy feet in height. This is hghted on two sides ; on one by a window, consisting of a plain slab, perforated with quatrefoils ; on the other, by a circular light, with spirally-curved muUions, one of the varieties of the Catherine wheel window. Th6 shafts of * It must be observed, however, that this church bears marks of two distinct periods, the earlier part being to the eastward of the tower. It is probable that this end corresponds more nearly in date with the Nunnery chapel tlian the western one, to which the following remarks are chiefly applicable. Those mixtures of style which have arisen from addition and reparation, arc a frequent source of difficulty to antiquaries. lONA. ANTIQUITIES. 11 the pillars in the church are cylindrical and plain, like those of the Norman era. They are surmounted by short capitals, often sculptured with grotesque and ill executed figures, and separated from the shaft by the corded moulding, which in some cases runs also through the walls on the same level. These pillars support ranges of pointed arches, of a curvature intermediate between those of the first and the second styles which charac- terize the two most beautiful periods of Gothic architec- ture, their soffits being fluted wdth plain and somewhat rude mouldings. A second and smaller tier of arches is perforated in the wall above these, sometimes circular, and at others terminating in a sort of trefoil head : a kind of machicolated corbel table surmounts the whole. I need not enumerate the other ornaments or circum- stances which are found in this building; the object being to describe these remains only in as far as is necessarj"^ for ascertaining the limits of the dates of their erection. The mixture of styles, of which the leading features have thus been given, bespeaks a date near to that here assigned to this building ; which is confirmed by in- numerable examples in England, where the same mixture prevails and where the real dates have been ascertained. I must nevertheless remark, while on the subject of dates, that the evidence respecting them to be derived from style in the ecclesiastical buildings of Scotland, is far less satisfactory than from similar works in England, uncertain as that often is; since in the former country specimens occur in styles which had in the latter been then abandoned, even for a century or much more, in favour of more recent systems ; as may be proved by the recorded dates. I may quote the Cathedral of Dunkeld as a remarkable example of this fact ; nor are the causes difficult to conjecture. From this consideration it is possible that the Cathedral of lona may be even more modem than the date to which I have referred it : we are certain that it cannot be earlier. It is unnecessary to 2 12 lONA. —-ANTIQUITIES. notice the buildings appertaining to the Nunnery or the Abbey, since they are mere ruins, neither presenting any interest, nor affording any elucidation with respect to their dates. Granite, found on the opposite shore of MuH, gneiss, hornblende slate, and clay slate, the produce of the island itself, enter conjointly into these structures ; the roofs having been covered with mica slate, and the carved ornaments of the interior executed in sand-stone, brought, possibly, from Gribon in Mull. It is impossible, as I have already said, to form any conjecture respecting the unsculptured grave stones, or even about those which are rudely sculptured and bear no inscription. Tradition is on this subject of no value. It is sufficient to remark, that one of the earliest actually bearing a date, is the tomb of Lachlan M'Kinnon, in 1489. That of the Abbot M'Kinnon, which is in the choir of the cathedral, is of 1500; that of the Prioress Anna, of 1511. These inscriptions are in the Saxon character. There are also some traces of inscriptions in the Gaehc alphabet to be seen, but undated. It is perhaps incumbent on a mineralogist to state, that the Abbot M'Kinnon's tomb is neither formed of black marble, nor basalt, both of which have been asserted by different observers ; but of a micaceous schist, with a mixture of hornblende. The botanist must also be told that the Byssus lolithus does not grow on this tomb, as mentioned by Lightfoot, but on that of the Abbot Kenneth opposite, one of the Mackenzies of Seaforth. The sculptures on the best of these are but indifferent, if we except those that consist of mere tracery ; in which we are often at a loss whether most to admire the persevering intricacy of the designs, or the refractory nature of the material in which they have been executed, which is, I believe invariably, mica slate. Swords, ships, and armorial bearings, with ill executed bass reliefs of warriors, form the chief objects of the others. The ships are the most interesting, as serving to give us an idea of the knowledge which these islanders lONA. — ANTIQUITIES. IS possessed of navigation. The prow and stern are alike, and protracted into long curves upwards, like many of the galleys of the Romans. The latter is furnished with a well constructed rudder, and the rigging consists of a single square sail, placed a midships, the yard being slung in the centre, and furnished with braces aft. There is no appearance of a provision for rowing, nor is there any bowsprit. As the sail is fastened to the yard by four points only, it is probable that these ships, or rather boats, were but of small dimensions*. The occasional addition of the ship on the grave stone, may perhaps suggest the idea, that the persons whom these stones record were not interred on the spot, but that it signified the tomb to be honoraiy, like the /%f/ov of the Greeks, and erected to the memory of one whose body lay in a foreign land, or was buried in the ocean. The frequent mention in the ancient poetiy of this country, of the pleasure which the ghosts of the deceased derived from the contemplation of their own " grey stones," and the " calling on the ghost " to the habitation which was erected for the body, (the \J.y%ay&)y/a) present analogies between the Greek and Celtic superstitions on the subject of funerals, which, while they bespeak, like many other circumstances, a common, though distant origin, give a colour to this opinion. Thus also the Romans, " Gaudent compositi cineres sua nomina did — " and thus iEneas calls on Deiphobus, when he erects his monument on the Rhsetean shore. The number of the tombs here is great ; but much disturbance has taken place among them from recent interments; and it is probable, that many also have disappeared in consequence of the progress of agriculture, and the re-edification of cottages. At this moment, no conjecture can be formed respecting the distinct funereal allotments of the Kings of Scotland, Ireland, and Noi-way ; * PI. 30. Fig. 6. 14 lONA. ■ — GEOLOGY. of which we have nevertheless sufficient historical record in the narrative of Dean Monroe. It is not easy to wander among these remains uninfluenced by the re- collections they are calculated to excite. He who can here abstract himself from the living objects round him, and abandon his mind to the visions of the past, will long after recur, with feelings of pleasing melancholy, to the few hours which he has spent among the tombs of lona. Among other superstitions which have lost their hold on the minds of the people throughout this country, that of the Clach brath has passed away ; yet the boys of the village still supply a stone for every visitor to turn round on its bed ; and thus, in the wearing of this typical globe, to contribute his share to the final dissolution of all things. Many votive chapels seem to have once existed in this sacred ground ; but they have entirely disappeared, to- gether with the greater number of the 360 crosses, which it is said once to have possessed, and of which the greatest portion was, probably, also of votive origin. One of these is at present in Campbelltown, in good pre- servation : it is covered with an ornamental pattern, to- gether with a Latin inscription in the Saxon character. Three only remain at lona; of which one, entire and uninjured, is formed of a very long and thin slab of mica slate, and covered with ornamental sculptures of very perfect workmanship. The places of a few others which have been removed are still known, but the greater number is said to have been thrown into the sea by the orders of the reforming Synod. But I must pass from these pursuits to objects of less Qfeneral interest. Although the rocks which compose this island appear, on a superficial view, to be nearly identical throughout, and to consist of different varieties of gneiss, they will lONA. — GEOLOGY. 15 be found to present many circumstances interesting to the science of geology. It is difficult to reduce their descrip- tion to geogTaphical order, from the want of names and of a detailed map ; but I shall adopt what appears the most intelligible method, and trace them by the line of the coast. From the Town to beyond the Bay of Martyrs, the prevalent, or perhaps the sole rock, is a very black compact clay slate, which occasionally contains horn- blende, and, in some few instances, mica. There is, however, no real micaceous schist, or at least I did not observe it. It has been imagined to exist here, because most of the tombs and crosses are carved in a stone of this kind. It appears rather, that like the sand-stone in the groinings of the arches and the ornamental carvings of the soffits and capitals, it was brought from the main land, where it abounds along a considerable range of the western coast. Not far below the town and a little before the clay slate terminates, a vein of black basalt is found tra- versing it; the only instance of this kind which fell in my way throughout the island. I must now remark, that the opposite coast of Mull consists of a red large-grained granite, which has been much us6d in building the Cathedral. A few rocks of this substance are found on the neighbouring shore of lona, below the Bay of Martyrs ; one of which approaches so near to it as to be in contact with the schist: they are very evidently continuations of the rock of Mull. The schist at this place puts on a remarkable appearance. Externally, it displays a singular mixture of black and red. On breaking, it is found to be possessed of unusual hardness, the fracture being as acute and cutting as that of sihceous schist. In many places it loses its black colour and becomes grey ; in others, it is partially mixed and mottled with red felspar ; which at length increasing in quantity, it appears on the very verge of passing into \6 lONA. GEOLOGY. the gi'anite with which it is so nearly in contact. The sea prevents the actual and exact contact of the two rocks from being veiy fully examined ; else it is probable that a still more perfect series of this transition might be observed. The contact of argillaceous schist with granite is not rare in Scotland; but this is the only instance I have witnessed in which the interference of the latter is of such a nature as to produce the appearance of a real transition from the one to the other rock. Proceeding southwards along protuberances and chfFs of a substance which holds an intermediate place between clay slate and gneiss, a large mass of rock presents itself in a most conspicuous manner from the almost snovvy whiteness of its surface, which is visible from a considerable distance, even at sea. This white colour is found on examination to proceed from the decomposition of felspar, often so far advanced as almost to pass into porcelain clay. The rock itself is an irregular body of 100 feet or more in thickness, and 600 in length. It cannot be called a bed, but appears to be rather a shapeless mass ; having the same connexion with the beds of rock in which it is involved, as we usually find in serpentine, and not unfrequently in limestone, in similar situations. It is a compact felspar, having the small splintery fracture and imperfectly translucent appearance at the edges, of a rock sometimes described by the name of hornstone, which is a very frequent base of certain por- phyries. It is extremely refractoiy to the hammer*. In * There are few geologists who have not been occasionally foiled in their attempts to break such rocks witli tlie lianmiers in common use. 1 can, from long experience, recommend the following shape. It is either spheroidal, or ellipsoidal, the largest diameter in the latter case not ex- ceeding four inches. The weight need not exceed three pounds and a hidf. It is evident that the centre of gravity, and consequently the whole momen- tum, will be so directed towards the point of contact, as in almost every position to produce the maximum effect ; a circumstance only accident- lONA. GEOLOGY. 17 colour it is sometimes of a pure white, but more com- monly it is mottled, or stained with various shades of grey and brown : occasionally also it is of a greenish colour. Nearly similar in direction, and removed at a very small distance by a few beds of argillaceous schist, is found the well known marble for which lona has been long celebrated. I should rather say, the place of the marble, as nearly the whole of the bed has been long since removed. Portions of the walls, and those parts which were inaccessible to the quarry-men by reason of the sea, still remain to show what it has been. It is not a regular bed, since it terminates abruptly at a short distance from the sea, but is rather one of those isolated masses which are of frequent occurrence in many of the schistose rocks, as well as in gneiss. It is from twenty to thirty feet in breadth, and is elevated at an angle of 80 or 85 degrees, dipping to the eastward and directed towards the south, not above 100 yards of its length being- visible. All the useful parts have been wrought out, and, it is said, but without sufficient foundation, that the hio-h altar of the cathedral consisted of it. That altar has disappeared, whether in consequence of the superstitious avidity of pilgrims and visitors for its frag- ments, as report says, cannot now be determined. The texture of this marble is compact, its fracture splintery, and its colour white, often however with a slight greenish tinge. It is incapable of receiving a polish, its aspect remaining eitlier unifomily dull, or as if mottled with ally occuning in the long bladed prismatic hammer. From the sphericity of the surface, that momentum is also directed on one point, instead of being divided over a large space, as in the flat faced hammer, thus producing that vibration by which rocks are split. The relative position of the centre of gravity and the point of impulse, also prevents that injury to the wrist which so often follows a misdirected blow with the long hammer ; its lever acting against the operator. To these advantages I may add, durability ; the form preventing the steel from flying off, as in the common construction. VOL. I. C 18 lONA. GEOLOGY. streaks and drops of oil. In many places it has a schistose tendency, more particularly where it. approaches to the schist in which it lies. Here also it becomes mag- nesian, and passes by irregular gradations into a steati- tical calcareous schist. It contains in some parts distinct leaves of translucent schistose steatite having an ap- pearance and colour much like that of half frozen olive oil. Dark green foliated steatite is also found in it, accompanied by pale yellowish green and by dark green noble serpentine; which, when detached and rounded on the shore, are well known to the visitors of lona, and have been often mistaken for jade. I observed only one specimen containing asbestos. At the points of junction with the schist it is partially mixed with and passes into it, as the limestones which lie in mica slate are known to do, by a sort of alternating gradation. But it presents also a phenomenon scarcely to be expected here ; a contortion, by which it is irregu- larly drawn out, and waved together with the accompa- nying schist; the parts being involved and entangled in a confused manner*. As the beds of gneiss have all suffered contortion and derangement, there is, however, no reason why the accompanying limestone should be exempt, be the cause what it mayf-. The beds of rock which succeed in proceeding north- ward, appear to be generally placed in a vertical direction, but in a very irregular manner and with very little * PI. II. fig. 5. f In the posthumous papers of the late Doctor Walker, it is said, that green serpentine is found on the shore at the south side of lona, and that it may be quarried to any extent. Though prepared to look for it I did not find any other serpentine but that which is con- tained in the marble. Had it been small in quantity, I might perhaps have overlooked it; as among a wilderness of grey rocks of which the external aspect is alike, it is scarcely possible to examine the com- position of every portion ; but I can hardly conceive that any extensive rocks of this nature can exist here. I am more inclined to imagine bomc error in the statement. lONA. GEOLOGY. 19 semblance of a direct continuity. Those hitherto de- scribed are either argillaceous schist, or contain that substance as a leading ingredient; but at this point the siliceous matter becomes predominant, or, at least, very conspicuous. These rocks have frequently the ex- ternal aspect of granite, and have been mistaken for granite veins, which on a distant view they resemble. The granitic ingredient is a compact mixture of felspar and quartz, which is either disposed in laminai in the schist, or is mixed with it in an irregular manner. Thus the rock resembles a gneiss, though it consists, in strictness, of a laminated mixture of granite and clay slate. It alternates, as far as alternation can be pro- nounced of rocks so irregular, with the hard argillaceous schist. This rock is therefore either unprovided with a name, or else it must be considered as a variety of gneiss. If so, both the geological position and the definition of gneiss require to be corrected, since it alternates here with clay slate, and also contains it as an ingredient. Both these circumstances have, in fact, been prematurely limited, and the connexions and definition of this rock, like that of many others, established on too narrow a foundation. The structure of the remaining part of the island con- firms this view of the nature of the rock above described. It may be stated in gen,eral terms, as there appears nothing further in its various aspects requiring a minute detail. By degrees the anomalous gneiss gives way to one of a more ordinary structure, consisting of quartz, felspar, and horn- blende, disposed in a regularly laminated form, and containing beds both of common hornblende slate, and unlaminated granite; mixtures almost always found to accompany each other in this country in those gneiss rocks of which hornblende forms an ingredient. Still further towards the north end of the island, gneiss con- taining mica is to be seen, and of this, several varieties, 20 lOXA. — GEOLOGY. in every possible complication of structure and position, are continued to the extremity of the island. One peculiarity attends all the rocks of lona, namely, the oreat abundance of a substance hitherto considered as compact epidote, which is every where found in them. It is particularly prevalent in that bay, situated towards the west, known by the name of Port na Curachan, where St. Columba is said to have first landed, and which is marked by large conical heaps of pebbles, the penitentiary labours, as tradition says, of pilgrims to his shrine*. It here forms either large lumps or la- minae imbedded in the gneiss, and in some situations enters into it as a constituent part. In other places, it is found mixed with hornblende in various ways, or else serving for a base in which crystals of hornblende are imbedded; forming a rock which has been mis- taken for serpentine. As this substance does not appear to be very common, and seems to have in a great measure escaped attention, a description of its predominant characters will not be superfluous. It is generally pale green, at times approaching to yellow. The fracture is intermediate between the con- choidal and flat splintery, and it is exceedingly difficult to break, the fragments being slightly translucent on the edges. It does not easily yield to the file, and scratches quartz, while in return it is scratched by that substance. Its specific gravity is the same as that of quartz, but it has not been analyzed. From a comparison of the characters of numerous specimens selected from different places, I am inclined to consider it as a variety of compact felspar, and it will indeed be found to pass occasionally into the more common varieties of that substance. It forms a conspicuous portion of a gneiss abounding on the west coast of Ross-shire. ♦ In this spot is found that beautiful and rare Conferva, the atia of Dillwyn; not in streams, but in standing pools. lONA. — GEOLOGY. 21 The gneiss of lona is by no means abundant in granite veins. A few, however, but those of a small size, may be seen towards the middle and north end of the island. Here the schistus entirely vanishes and the rocks as- sume the more decided character of gneiss. At the same time, the regular disposition of the beds is much dis- turbed, or disappears altogether. I observed no other granite in the island than these veins and that rock near the Bay of Martyrs described at the beginning of this sketch. One porphyry vein may be seen traversing the gneiss in a small bay situated between the marble rock and Port na Curachan. It runs in a S. S. W. direction, dipping about 35 degrees, and is seven feet in thickness. It contains both mica and hornblende, imbedded together with felspar crystals in the common base of compact felspar. If there are any other veins of this description they escaped my observation. Only one other rock occurred to vary the uniformly tedious recurrence of the gneiss, and this is situated in the interior not far from Bloody Bay. It is a lime- stone, containing both mica and noble serpentine distri- buted through it in minute spots, in such quantity as nearly to overpower the calcareous base. It is a stone of extraordinary toughness. Whatever minerals lona may still possess concealed among its wearisome rocks, they remain to reward the toils of some future geologist. I shall scarcely visit it again, having fulfilled the Gaelic proverb, which in verse not less rude than the translation, asserts that There never yet came man to I* Who did not come times three. * I, («*t' sIox"*)? the Island, from the religious veneration attached to it. lona — I-thona; the Island of Waves. I-Columb-kil ; the Island of Columba's Cell. 22 TIllEY. GENERAL DESCRIPTION-. TIREY*. This island forms, together with Coll, a sort of chain, the general disposition of both being similar, and the mineral composition nearly identical. They may, indeed, in a geological point of view, be almost considered as one object, since their geographical discontinuity is attended with no change in the nature or disposition of their rocks. The sound by which they are separated scarcely exceeds half a mile at its narrowest part ; and its depth, which is no where more than six or seven fathoms, is rendered in many places much shallower by interspersed rocks and sand banks. The position of the chain, extending from the southern end of Tirey to the Cairns of Coll, is direct, and on the S.W. by W. rhumb; the total length being 25 miles, or a little more. The shores offer frequent, but not extensive indentations, consisting of sandy bays separated by ridges of rock. They abound in the common fuci, which are manufactured into kelp, and are frequented by the fish usual in these seas, cod, plaice, coal fish, and gurnards ; but the fisheiy forms no regular part of the pursuit of the inhabitants, as it does in many of the other islands. Tirey is the soutliernmost of the two, its length being twelve miles, and its greatest mean breadth about four. Its general surface is flat, and so low that it is scarcely elevated twenty feet above the high water mark, affording a free passage to the western winds, which sweep it with unrestrained violence. Having no trees, and scarcely any enclosures to check their force, the gales pass over, the * This name has been a source of difRculty to Gaelic etymologists. Tu', a region, (Gaelic.) Tirim, — dry, — is more appropriate. In the Swedish, Tiur, a bull. Muck, Canna, Soa, and Inish Capel, all offer analogies in favour of this derivation. See the general map. 2 TIREY. — GENERAL DESCRIPTION. 23 island as they do over the sea, materially disturbing the operations of agriculture by dispersing the seed together with the loose and dry soil; and often breaking down the crops both of corn and potatoes when these have attained to their full growth. The southern half of the island is almost an uninter- rupted plain, with a few scattered rocky elevations; but towards the northern end the rocks become numerous, and, as in lona, at length occupy the greater part of the surface, impeding the cultivation of the soil, and condemning it to perpetual pasturage. At the northern extremity there are considerable accumulations of blown sand. Notwithstanding the general flatness of the surface, Tirey presents three distinct hills near its southern ex- tremity, the highest of which scarcely attains the elevation of 400 feet. A few low hills tov/ards the northern end range from 30 to 60, and would scarcely be noticed in a country less flat than this. It contains two small lakes, one at its southern and the other at its western side, be- sides some smaller pools ; but presents no stream or running water except that which is discharged from one of the lakes and applied to the use of a mill. This want of streams arises from the flatness of the land, as, although the climate is far from wet when compared with the neighbouring high lands, there seldom passes a week in any season of the year without rain. To compensate this defect, water is procured by digging, within a few feet of the surface ; and in various parts of the island where there is a want of drainage it is also found producing marshy spots. The soil is in general light, consisting of sand mixed with peat earth ; but the island is remarked for its fertility, forming, in proportion to its extent, one of the most valuable tracts of land in these seas. This fertility is partly the result of the calcareous nature of the sand, which contains, together with quartz, a large proportion 24 TIILEY. GENERAL DESCRIPTJON. of shells, and partly that of the regular and constant moisture which it derives from its climate and exposure^ as well as from its flatness. It produces but little peat for fuel, and this forms one of the greatest deductions from its value ; the inhabitants being under the necessity of bringing this important article from the opposite coast of Mull. The regular state of moisture in the soil is every where indicated by the Iris pseudacorus. Polygonum viviparum, and other aquatic plants, which are found flourishing in every corn field ; little concern being felt, in the Highland system of farming, about the growth of weeds. The natural pastures, which, from their position and soil, are the driest, are surprisingly rich, and pro- duce white clover in such abundance as nearly to exclude the graminecc; that plant being the invariable tenant of all the calcareous soils of the Highlands. A remarkable plain towards the centre of the island is known by the name of the Reef, and comprises a space of 1250 Scottish acres, (1562 English,) as flat as the sea, and scarcely interrupted by a single eminence or even by a stone ; offering a singular spectacle of richness and verdure. This plain, from a dread of the effect of the winds should the surface be once broken, is kept in a state of perpetual pasture. In the want of wood, Tirey resembles many of its neighbours, but is even more completely deficient in this article than perhaps any one of them ; since, with the exception of the Salix argentea of Smith, (the arenaria of Lightfoot,) it may truly be said not to possess a ligneous fibre. Tirey suffers but httle from the sand inundations, except towards its northern end. There is consequently but little apparent change in the coast line, even on the western side; where, if in any part, the changes from this cause would occur ; although, if we are to believe Martin, the Reef was in his day subject to inundation from the sea. Although the want of shelter in the island may be in many respects injurious to agriculture, yet it is TIREY. GENERAL DESCRIPTION. 25 doubtless one of the leading causes of the general fertility of the soil, and of the little injury which re- sults from the sand drift, the effects of which in many of the Western Islands are so conspicuous, and often so injurious. In consequence of its level and unobstructed surface, the sand is distributed by the winds over the flat parts of the island in so equable a manner as to im- prove the whole by the perpetual renewal of a calcareous manure ; while it scarcely any where accumulates to such a degree as to suffocate or repel vegetation. The differ- ences in this respect are very apparent, where the rocky surface, affording local shelter, causes the sand to accu- mulate, as on the northern end of this island and through- out the whole of Coll ; and they will receive further illustration hereafter, when the state of the sandy accu- mulations on the western shores of the Long Island are described. I may add, that the moisture of Tirey, arising from the causes formerly stated, affords a powerful pro- tection against the blowing away of the soil ; by maintaining a perpetual coat of vegetation on the surface, which prevents the wind from acting on it. From these circum- stances, the cultivated land of the island is perhaps in many cases less profitable than it would be in pasturage, were it possible to calculate its value on any other agricultural system than that which the extreme population of this island, as of many other parts of the Highlands, renders necessaiy, or rather indispensable. In consequence of this state of the soil, cross ploughing is rarely used, but the seed being sown on the first furrows, is harrowed in by a light harrow, so that in springing it assumes the appearance of a drilled crop in eveiy respect but cleanness ; since the intermediate sod is generally occupied by an equal line of weeds. Under even this miserable proceeding, good crops of barley, oats, potatoes, and flax are produced; sown grass and turnips having here, as in most of the islands, scarcely yet found their way into the agricultural system. The chief manure in use, is that of drift fuci. Q6 TIREY.^ — AGRICULTURE. As the frequent recurrence of this subject in the different islands might lead to repetitions inconsistent with the principal object of this work, it will be more useful to give a sketch of the agricultural condition of the country in general, reserving for their proper places any peculiarities by which the several islands may differ in practice from each other, and from the system generally prevalent. Without such a sketch, it would be impossible to render remarks of that nature intelligible; on account of the ancient and imperfect practices by which the agriculture of the Western Islands is charac- terized*. The natural connexion indeed between the soil of any country and its geological structure is, except in the case of some alluvial districts, so intimate, that it is impossible to treat of the geology of a district, without bestowing at least a transient attention on this subject. It would be overrating the advantages of geological knowledge to assert that it can offer much aid to agri- culture, yet it may still be a useful auxiliary in certain cases ; independently of the pleasure which is always derived by the scientific labourers in any pursuit, from tracing the mutual aid which the several branches of science and art afford each other. To point out all the circumstances in which the study of geology may bear on the pursuits of agriculture, would lead into a length of discussion ill calculated for a work of this nature. In describing the system of agriculture followed in tTiese islands, I shall confine myself chiefly to the ancient practices, which are still the most prevalent; it would be superfluous to dwell on the recent improvements which * I shall hereafter merely notice such facts as may occur to illustrate this art, just as they may chance to present themselves in the course of this investigation. Such notices may possibly interest those to vyhom the country under review is but little known ; and they will at any rate serve to enliven a subject not sufficiently various to keep up the attention of the general reader. TIREV. AGRICULTURE. 27 have been adopted, corresponding as they do with the more perfect systems in general use. Time is, however, rapidly diminishing the number of these ancient usages, and the progress of improvement is, if slowly, yet cer- tainly, confining them within a smaller circle. When ancient systems are discovered to be prejudices, their downfal is not distant. To make such errors matter of reproach is unjust : they are of all times, and have been accompanied by similar errors in all the branches of human knowledge. The causes by which they are here still maintained are abundantly obvious ; and it is rather matter of surprise that so much has been done in a period so short, than that any thing should remain to be accomplished. Under the ancient system of policy and manners, a scanty and imperfect cultivation of corn was limited to the few spots surrounding villages (if such they might be called) which were immediately under the eyes of the cultivators, and thus more secure from destruction by an enemy: a consideration of importance at a time when eveiy great family was an independent state, and these states were in perpetual hostility. Sheep were, from their habits, ill adapted to the system of pasturage connected with this condition of things, the chief wealth of the inhabitants consisting in cattle ; the con- stant objects of depredation, and the fruitful sources of war. Under such a system, a scanty population with difficulty found a supply of food, and the obvious con- sequences are too apparent throughout the whole history of the country, to a period even as late as the middle of the last century. The introduction of the potatoe, and the increase of sheep pasturage, made the first material change in the system; and, in consequence of these innovations, the population increased and has continued to increase to this day. But here the improve- ment may be said to have ceased ; at least no radical additions have been made, although modifications of 28 TIREY, AGRICULTURE. both these great steps, as well as of many parts of the ancient practices, have been introduced, so as to pro- duce in effect changes of great importance. The reader will easily trace in the following details that which has been done, and that which is yet wanting to bring the more antiquated districts to a level with those which have already adopted the improvements of their more enlightened neighbours. The first step in innovation is the most difficult. The stranger who for the first time visits this country, sees with surprise scanty crops of corn distributed in detached beds of earth which have been collected for its cultivation ; or so disposed among a labyrinth of rocks that scarcely an uninterrupted space of half a rood, often of only a few square yards, is to be seen together; while the shortness of the straw and the thinness of the ear, mark the struo-gles which even this miserable crop has made for existence. He again sees this crop exposed to the storms of August, or drenched in the rains, perhaps for weeks after it has been cut down, and probably laments that human industry should be so far mis-directed ; while, like many even of the natives themselves, he w^ill condemn any further attempts to increase or improve this department of rural economy. The prevalence of this opinion among the natives has been one leading cause of the very evil thus lamented ; since by tying them down to the ill-conducted practices of their ancestors, it has prevented those improvements in the agricultural department of farming which more experienced observers and more enterprising cultivators have shown to be possible. It will indeed be soon perceived by any observer who will bestow attention on the subject, and abstract the effect of first impressions, that the efforts of art are in this country rarely directed to counteract the injuries or supply the deficiencies of nature; that it too often co-operates with them, and that, under a system adapted to the wants and pecu- TIREY. AGRICULTURE. 29 liarities of the climate and soil, of which the severity and defects are too often overrated, improvements of a radical nature and a considerable extension of the present system may be effected. As far as climate is concerned, earlier as well as better crops will be the result of improvements in the methods of tillage ; and the harvest, of which the uncertainty chiefly depends on its lateness, will be ready at a better season. A further effect also of an improvement in the system, would be a more regular occupation throughout the year; of which a great portion is now spent without employment, while at one particular season its whole accumulated labours are pressing on the farmer for attention. The introduction of green crops, for example, a necessary part of the improved or convertible system, would tend to divide the occupations of the year, and at the same time preserve the stock of the farm fit for labour when wanted. Such also is the connexion between pasturage and agri- culture, that an increase in the latter will enable the insular farmer to rear a greater number as well as a better breed of cattle and sheep, and to deliver their produce to the market, not only of superior quality, but m better condition. The ancient system consisted in producing crops of corn, either with or without manure, as that could be procured, from the richest fields ; and this practice was continued till the land refused to bear any longer ; such grass or weeds as happened to grow on it, were then suffered to accumulate for a series of years, and the same process was repeated in a perpetual rota- tion. The natural pastures were at the same time grazed by the indigenous cattle, by which they were almost invariably overstocked to such a degree, that numbers died at the end of every winter. Finally, the farms, held in run-rig, or common, were overrun with superfluous horses. Such is still the funda- mental part of the present system^ where better practices 30 TIREY.; — AGRICULTURE. have not been introduced ; and these are far from bearing even a tolerable proportion to the whole. Isla, Colonsa, Gigha, Sky, Mull, Coll, Rasay, and a few tracts in the Long Island, exhibit, in fact, almost the only excep- tions. If the details of the tillage be examined, they will be found as defective as the general plan. No winter or autumnal ploughing is used, but this operation is con- ducted in the spring in a most inefficient and slovenly manner. The traveller who chances not to arrive until the harvest is ready, may be surprised to see so many examples of what he will imagine to be the modern drill husbandry, but will soon discover that the appearance arises from the seed having been sown after one ploughing, as mentioned in Tirey. Thus it is lodged in the furrows, where it is afterwards imperfectly covered by a bad har- row ; producing a late crop, yet not a clean one, while the advantages arising from deep ploughing are neglected. Cases indeed occur of soils so light and sandy, as in Tirey and many parts of the Long Island, where neither the srround nor the seed could resist the efforts of the wind, were it thoroughly ploughed. In such cases the interest of the farmer, as well as that of his neighbours, would be to avoid ploughing altogether, and to lay down such fields in grass. But two causes prevent this, the tempta- tion offered by sea weed, and the smallness of farms ; which compel the little tenant, who possibly has no other land but a driving sand, to procm-e a crop of corn from it on the best terms he can ; an argument among many which will occur at every step, for a different division, and in many cases for an enlargement of farms. It would lead into details inconsistent with the object of this sketch, to particularize the defects in harrowing, scarifying, weeding, and other operations connected with ploughing ; or to notice the total absence of some, such, for instance, as that of rolling. The reader must perceive that under the system de- TIREY. AGRICULTURE. 31 scribed, scarcely any notion is entertained of the rotation of crops, or of the advantages to be derived from it. Fallowing is not practised, perhaps it might not often be required. Where potatoes have been planted, either on old ridges or for the bringing in of waste lands, a large quantity of manure is applied ; and this serves generally for the crops of corn that are to succeed, although a small quantity is occasionally used with them. Barley thus succeeds to potatoes, while that again is followed by oats for two or three, or even a greater number of years, till the land fairly refuses to yield more. In other cases, the barley is sown with manure, and the oats follow as before. Turnips, pease, beans, grass seeds, and clover, are unknown ; and the art of farming is thus at least reduced to a system which it requires but little knowledge to conduct. Not so, however, the expense, which is great in proportion to the imperfec- tion of the modes and the scantiness of the produce. It is no diminution of the expense that it is not found in the farmer's accounts ; that his labour and tlie labour of his family are reckoned as nothing; and that the keep of his useless horses does not enter into his calculation. His want of calculation would be a more appropriate term, since the slightest attention to this subject would show, that the cultivation of a few acres could never repay the expense of four or five horses and as many people, were he even rewarded with a full crop. If it be considered that his crop sometimes does not produce the double of his seed, and that four returns in oats are a good crop, we can scarcely set a sufficient price on his grain, or discover by what means he is enabled to pay any rent for the land on which his industry is thus wasted. Besides barley and oats, a small quantity of rye is cultivated in some of the sandy islands, since a crop of this grain can be obtained after oats have ceased to grow . These crops are both short and thin. 32 TIREY. AGRICULTURE. The species of barley exclusively used is bear, which, from its early ripening and other qualities, is best adapted to the climate ; and which seems not to admit of any bet- ter substitute, or of any other improvement than that of a more careful selection of the seed. The insular farmer, contrary to the general practice, and from mistaken notions of economy, makes choice of the worst part of his grain for this purpose. The same praise cannot be given to the species of oats which is in most use. This is a small dark grain, commonly called the grey oat, and it is of a most unprofitable nature. Three returns are the average produce of this grain, the aspect of which, when in a state for cutting, is such, that a stranger would often with difficulty believe that any serious designs of that nature were entertained. The seeds, or else the soil, are often so full of the Holcus avenaceus, that many square yards will sometimes occur in a field, not containing one plant of oats in the yard. Notwith- standing the small value of this grain, and the scan- tiness of the produce, the natives are still strongly attached to it on account of its power of resisting high winds, as it does not lose the little grain which it possesses by shaking. The introduction of a better oat would be among the first, and apparently among the easiest improvements in the agriculture of these islands. The sickle is invariably used in reaping all grain, although the necessity of expedition in the process of harvesting, arising from the uncertainty of the climate, would suggest the scythe as preferable, wherever the roughness of the surface does not prevent its use. Great part of the straw is used in thatching, and the thatch being ill applied requires constant renewal, inducing a wasteful expenditure of this scarce and useful article. An additional waste is produced by the process of burning or graddaning, as it is called; used in some places for converting the corn quickly into bread. The grain is roasted while in the sheaf, in the flame of the straw, TIREY. AGRICULTURE. 33 more than a third part of which is thus destroyed : the taste of this bread is agreeable, although its com- plexion is black ; but the practice is now becoming rare. More usually the oats, like the barley, are kiln- dried in the ear and then ground into meal. The quern is now rarely to be seen, as mills have been erected in most of the islands; but it is. still to be found in some of the smaller ones, forming a most laborious occupation for the women, on whom this, as well as many other parts of the economy of a highland family, falls. The several sorts of grain are formed into cakes in nearly the same manner, by tempering the meal with water and toasting it before the fire ; an operation requiring a perpetually recurring and daily labour. A portion of the barley is sometimes converted into whiskey, and almost always in an illicit manner : but this trade is in a manner engrossed by certain districts, from which others are supplied by means of a fraudulent commerce ; the division of labour, but little known in the islands, having found its way into this branch of their rural economy*. The cultivation of potatoes is practised in these islands to a great extent, and with success ; and the effect of it in bettering the condition of the people, and in in- creasing their numbers, has, as in all other instances, been very great. It is, perhaps, not over-rating the use of this root to say, that it forms more than two-thirds of the food of the people. It was not introduced without diffi- culty ; but such a breach once made in the philosophy of a country is an earnest of the possibility of further improvements when sufficient argmiients can be produced in their favour. Such arguments ought to be founded on example and demonstrable success ; since these are the only ones which the condition of such a country * Since this was written, a change of the system of revenue, as it affects the highland distilleries, has been effected by the legislature. It yet remains, however, to be seen what its effects will be, as well on these illicit practices as on the state of agriculture. VOL. I. D 34 TIREY. AGRICULTURE. admits. It is true that there are circumstances which seem at present to be a bar to any innovations, even though fortified vrith these arguments ; and which Time himself, the great innovator, cannot remove till many preparatory inroads on the present system shall have been effected. But the detail of these would lead into econo- mical discussions of wide extent, too wide at least for the brief sketch which I proposed to give. The general mode of cultivating potatoes is in lazy- beds, as they are called, the intermediate earth being often removed, even to a great extent, on thin rocky soils or on peat mosses, and large drains being thus left between them. These beds are highly manured, generally with sea-weed, since the greater number of farms, indeed nearly the whole population of the islands, lies near the sea. The sets are dibbled in, and are in general carefully weeded ; the care bestowed on this justly favoured crop forming a strong contrast to the prevailing slovenliness of the insular agriculture. Receiving this article when its treatment was well understood, the Highlanders neces- sarily took with it the rules for its cultivation, and no breach of ancient habits was required. The beds which I have described are made up either by the spade or the more powerful instrument the caschrom, often on the bare rock, and they present a singular spectacle to the lowland or English traveller Avho for the first time witnesses this mode of culture. He will naturally revolt at what he considers misdirected industry and extravagant expense, not reflecting that the divided nature of the tenures and the superfluity of the population cause this waste of toil, and that such a practice is the necessary consequence of the present state of the country. An advantage at first not contem- plated is also the result of this system, namely, the acqui- sition of much arable land from the waste ; since it is by the potatoe culture that the peat mosses are brought into a state of aration. There can be no question respecting the TIRFY. AGRICULTURE. 35 imperfection and expense of such a system of cultivation^ abstractedly considered : but the question here, as in many other cases, is not about that which is best, but that which is most suitable to the present state of the country. The enlargement of farms and the conversion of tenants into labourers, or, what will necessarily be the other alternative, the removal of the present population and the introduc- tion of a more able and poAverful class of tenantry, must precede the introduction of a cheaper husbandry with respect to this root, namely, the drilling and horse-hoeing system. He who has but an acre to cultivate, must cul- tivate it with his own hands ; he who has no plough, must use a spade. The caschrom here mentioned is much used in Sky and in the Long Isle, and is an instrument of considerable efficacy and power : it is rather a plough than a spade, and will perform twice as much work as the latter with the same labour. It is a singular circumstance, that an instrument so simple and so nearly a-kin to the plough, and at the same time of apparently great antiquity, should be limited to this country. No trace of it is to be seen among those drawings, whether Egyptian or Hindoo, which represent the plough in its most simple and original state. It would seem to have been the invention of man where the co-operation of animals in his agricultural la- bours was unknown. Its advantage in this country over the plough arises from its being applicable to the cultiva- tion of rocky ground where a plough cannot be used, or to that of boggy and soft land where a horse cannot walk. Many districts, now in a high state of cultivation, could not otherwise be tilled ; and as long as the present system continues, the caschrom* will maintain its ground. As the cultivation of grasses forms no part of the ancient system, the hay of the islands is the produce of natural meadows, and, in many cases, of waste scraps of land, whence it is cut and saved at a great expense of * PI. 30, Fig. 4. 36 TlllEY. AGRICULTURE. labour and time ; while it is also contaminated with rushes and other aquatic plants, the usual inhabitants of such situations. Scarcely any attention, except some feeble attempts towards draining, is bestowed on the meadows ; ^vhich are left as they were found, to the care of Nature. Hence their produce is deficient both in quantity and value, while the hay being rarely secured sooner than the corn is frequently damaged, and even the total loss of the crop, in consequence of its lateness is not uncommon. The cultivation of flax is carried on, but to an incon- siderable extent ; and, as may easily be imagined, not in the best manner. That of hemp is still more limited ; indeed it can scarcely be said to exist, since it is only occasionally seen in small patches ; the produce being con- fined to the very limited consumption of the country, in the shape of twine or fishing lines. Whether these two substances may be considered advantageous or otherwise when viewed abstractedly in an agricultural light, the question with respect to these islands is of a different nature. Where the operations of agriculture are carried on, in the manner already described, by a superfluous number of hands, and where much time will consequently at certain portions of the year be unemployed, it must be desirable to invent new modes of occupation, until the division of labour, the sure concomitant of improvement, shall have taken place. The manufacture of these sub- stances for the current wants of the community requires little or no capital; and the produce can always com- mand a ready market ; thus holding out employment to those who are inclined to profit by it, and operating as a stimulus to a people whose industry is not dead, but, for want of objects, dormant. The ultimate effects may in other respects be even more advantageous, though less immediately obvious ; namely, a taste for occupations different from those of agriculture, whicli notoriously engross too large a proportion of the Highland population, and a demonstration that the means of living TIllEY. AGRICULTURE. 37 are to be procured by other methods than the possession of land. The present habits of subsisting poorly on the produce of land by an alternation of severe labour and idleness, have no tendency to correct themselves. The forcible establishment of manufactures and of fisheries are projects only for inconsiderate benevolence : it is by the gradual change of opinions and practices, by the presentation of new motives and the creation of new desires, that the state of society must be changed. All that which ought to follow, will proceed in its natural order, without force, without loss, and without disappointment. The system of pasturage forms the remaining and the chief branch of the rural economy of the islands. It is evident that the high mountain pastures which constitute the principal part of the country, are in a great measure incapable of improvement ; but the natives seem unfor- tunately to have formed the same opinion respecting the lovv^er ones, and thus to have neglected those obvious improvements of enclosing, top-dressing, draining, or laying down to grass after occasional cultivation, by which their value would be so materially increased. The possible improvements of that which may be called waste land, may also be considered as pointing rather to an ameliorated system of pasturage, than to agriculture properly speaking. The chief part of such wastes is moor land, formed principally of a mixed and dry peaty soil, commonly thin, and placed on a bottom of gravel or coarse clay ; the produce consisting chiefly of heaths, with several coarse grasses and some mosses. Where these lands approach the sea the growth of such plants is checked, and at last destroyed ; a fine green pasture succeeding, which, under proper management, is capable of producing good crops of corn. The shores of the Lono; Island, wherever the numerous inlets of the sea intersect these moors, show striking examples of the fer- tiUzing powers which the vicinity of the salt water pos- 38 TIREY. AGRICULTURE. sesses ; or else of the Influence which it exerts in prevent- ing the growth of bog plants and the consequent gene- ration of peat. The same effects are produced by the application of calcareous manures ; under which treatment the useless plants disappear and are succeeded by clover and valuable grasses. An excellent black mould is formed in a few years when cultivation has followed that practice ; and this is more particularly the case in those islands where the substratum is of trap. The same effect of converting the moor land into green pasture is produced by turning the surface, while the pasturing of cattle pre- vents it from returning to its primitive state. The ex- pense is in many cases a serious obstacle to any of these modes of improvement, and in certain situations an insur- mountable one ; but they are, nevertheless, applicable to many thousands of acres now nearly useless, from which the returns would be both immediate and profit- able. Those who have wandered over the brown and bare lands of Lewis, or of Sky, may easily imagine the different aspect these islands would assume were such improvements carried into effect. That they will be effected at some distant day there is no reason to doubt. Under circumstances of equal difficulty, of less knowledge, and as little wealth, have some of the principal pastures and cul- tivated lands of Britain been rescued from heath and barrenness. With regard to the improvement of mountain land, the pasturage of sheep appears the only expedient. This is well known to banish heath and improve the natural grasses ; and the extension of this practice, which is not yet fully acted on although its value is well understood, will ultimately do all which art will probably ever effect on soils of this description. The methods of reclaiming peat mosses are, at present, perfectly known, and the experiments of many enlight- ened cultivators have proved that the profits are suffi- ciently tempting. If there are obstacles to tlie further TIREY. AGRICULTURE. 39 increase of this kind of improvement, they must be sought for, not in want either of knowledge of the means or of conviction of their efficacy, but in those circumstances in the condition of the people, the deficiency of capital, the smallness of the possessions, and the want of secure leases, which in every situation must be impediments to improvement. The introduction of the potatoe system has, even in the hands of the smallest tenants, led to the im- provement of much peat land, as I already remarked, for here the reward immediately follows the labour ; while the means, as far as to the extent yet tried, are in the hands of every one. He who has made the first step has overcome his inertia, and will easily be induced to make a second if he has the means to make it, and a continuation of the sti- mulus is held out to him. Much has been already effected in favour of the Highland tenant by the division of farms, which has for the first- time given him an interest in his possessions, and has also served to demonstrate to him how much his prosperity is connected with his industry. Under the crofting system much land will yet be re- claimed ; but it is plain that nothing short of a greater capital, larger possessions, and longer security, can do much for the lands that are yet in a state of nature. These are the leading wants of the system. It must be added, that there is an obvious want of industry in the character of the small Highland tenants, although much paradoxical and contradictory matter has been brought for- ward on this subject, by contrasting their apparent indo- lence, their neglect of the most simple and obvious improve- ments of their comforts and of their condition, with the activity and perseverance which they occasionally show in other pursuits. As an excuse it may indeed be admitted that there can be no exertion without a motive, no industry without a good to be obtained, or an evil to be shunned. A great part of the indolence of the inhabitants is the con- sequence of a positive want of occupation ; much more of it arises from the absence of wants, from contentment with their 40 TIREy. — AGRICULTURE. present situation. It is not too strong a statement to say^ that discontent is the basis of all human improvement ; the motive to action without which man would yet have been feeding on acorns and clothing himself in skins. The first step towards the improvement of the country is to excite wants ; and this must be the result of local example, or of a freer communication with more enliohtened coun- tries and a knowledge of more accumulated comforts. Little of this example exists in the remote islands, in which the want of communication is also, from various circum- stances, almost complete. In the vicinity of towns and of the improving countries, the change is palpable and rapid. It would not be difficult to point out means by which its progress could be accelerated in the remote districts ; but the discussion would carry me beyond the bounds pro- posed in this sketch. It is well known that the rearing of black cattle for exportation forms the basis of the pasturage of the islands. These are almost invariably exported in a lean statCj and are generally purchased on the spot by itinerant drovers ; the risk and expense of freight making, in many cases, a serious deduction from the value of the animal. No attempts have been made to fatten stock for salting ; a plan which, with great probability, might in many of the islands be adopted with advantage. Nor is there any system of dairy farming, further than is required to meet the current demands of the cultivator himself; since neither butter nor cheese can be said to form articles of export. The want of winter food is indeed, from the defects of the agricultural system, an obstacle to these practices ; and it is a serious detriment also to the very system of exportation under which their cattle are at pre- sent reared. In consequence of it many animals die in winter ; and even those which survive are at the return of spring so reduced as to be of far less value, even when made fit for travelling and exportation, than they would be under a better plan of feeding. The cultivation of artificial TIREY. AGRICULTURE. 41 crops, and a system of enclosure and division, are the obvious and necessary preliminaries to any amelioration in this department of insular farming. The breeds of cattle are small, and do not materially vary in the several islands ; except where they have, in the improved ones, experienced recent attention : and it seems generally thought that they are not susceptible of any exchange for the better, nor of any other amehoration than such as may be founded on a good selection of individuals. Compared to the breeding of cattle, that of sheep must be considered as a modern improvement, or an innovation upon the ancient system. Formerly this animal was only reared for do- mestic consumption ; and St. Kilda is now the only island where the ancient breed, supposed to be of Nor- wegian extraction, is still to be seen retaining exclusive possession of the soil. This wretched race is nearly extirpated every where else, having given way to that variety known by the name of the Tweedale breed ; the Cheviot having been as yet but partially introduced, and not being at present expected, from the circumstances of the climate, to gain an extensive footing*. The deficiency of winter food is the principal defect in the sheep farming, as it is in the case of the black cattle ; but in both there is a still more serious evil in the management, namely, the overstockino- of the farms. This excess in the num- bers both of the sheep and cattle is visible almost every where, and its results are such as might be expected. It will naturally subside as joint farms become divided and small ones consolidated by the spreading of improve- ment; besides that it will gradually cease to be felt as the cultivation of winter food increases. The opinions respecting the propriety of an increase of sheep farming have been unfortunately so much connected with the * The sheep farmers of Sutherland are now of opinion that this variety is perfectly adapted to the climate of the Highlands, and that its more extended introduction will be an essential improvement of the present system, — August 1818. 42 TlliEY. AGRICULTURE. notions of depopulation and emigration, and with all the ill-founded prejudices which these odious terms scarcely ever fail to produce, that the introduction and extension of this practice have always had to con- tend with a host of obstacles and difficulties, here, as in every instance where it has first been adopted. The progress of agricultural improvement in England, as well in this case as in other endeavours to change the ancient habits, is only the prototype of that which is here but beginning. It is superfluous to discuss the advantages already derived from sheep farming ; the subject is indeed too trite to require notice ; but it is proper to remark, that in some of the islands under consideration it is deservedly less an object of attention than in the mountain farms of the main land or of those islands which lie near its shores. The sheep does not bear sea carriage well, and is therefore a commodity of far less easy trans- port than cattle : fortunately there is not a very large proportion of the Long Island, (the only tract from which the transport of sheep would be difficult,) that would be more advantageously occupied by sheep than it is by cattle. Few circumstances in the system of Highland farming are more remarkable to a stranger than the enormous number of horses kept ; a practice, however, which is fast expiring. It is a moderate statement to say, that there are three times more than are necessary ; since there was recently a common farm, even in Sky, possessing forty horses, where the whole work might have been performed with six. Tirey lately contained fifteen hundred, a number probably ten times greater than its real wants, but these have been much reduced by means which however unjustifiable it is unnecessary to detail. Of the causes which have led to this wasteful superfluity, some have been unavoidable ; while others, having been the result of bad practices now disappearing, are themselves vanishing without specific remedies. The want of carriage TIREY. — AGRICULTURE. 43 roads, and the transport of peat from the hills and of kelp from the shores, must still, as they have always done, produce a necessity for a greater number of horses than would be required if carts could be used. Their inefficacy for labour arising from their bad condition, and from their want of stature and strength, also add to this necessary number a proportion which would be materially reduced if a better fed and stronger race was adopted. The division of the land into small farms leads here also, as it has every where done, to an unnecessary multiplication of them ; the number required on a small tenement being equally capable of doing the work of a larger one. In a greater degree this excess has resulted from the pos- session of common farms, every joint tenant, from pride or rivalship, thinking it necessary to keep as many horses as possible, whether he has work for them or not. It has arisen in some measure also from the undefined value of land when thus held in common ; it seeming seldom to enter into the conception of the small tenant that a given portion of land could feed but a given number of animals, whether held in common or not, and that the diminution of the stock of his useless animals would enable him to increase that of his useful ones. The crofting system, where every man's lot is visible to him- self, has tended to facilitate his conception of the value of land, and to make him economize that of which he can now see the extent and powers ; and it has thus aided to diminish, in a great measure, this preposterous evil*. The breed of horses in question, however de- ficient in strength and weight for agriculture, is well known for many useful qualities, and for its adaptation to the climate : those of Tirey were noted for their beauty as well as their small size, but they have been exter- * The tax on horses kept for pleasure has been sometimes resorted to as an expedient for this purpose ; and the mention of such an expedient may, perhaps, amuse the poUtician of the south, who is unacquainted with the internal policy of the Highlands, if policy it can be called. 44 TIllEY. — AGRICULTURE. minated by the violent means above alluded to. When carefully managed and selected, the Highland horses admit of great improvement ; but are injured materially by w^ant of food and shelter, and by other modes of ill treatment. They are sometimes shod on the fore feet, often not at all ; yet when habituated to it, w^ill travel without injury over the most stony roads, the feet acquiring an unusual degree of hardness, and justifying, as well as the practices of the ancients, the notion that the shoe may in many cases, and under certain systems of work, be entirely dispensed with. Many of the islands, and among these Tirey and Coll, do not even possess a shoeing smith. There is no regular system of breeding for exportation, unless it be in Isla and Jura ; and even in these it is not carried to any extent. A few are taken from Sky and Mull by the Irish, but they seem rather to be the last remains of those which are fast becoming unnecessary for the country; and which, though they may still be propagated for a time till the improvements are fully adopted, will pro- bably soon altogether cease to be produced. Asses and Mules are unknown in these islands, although they would probably be found of use as substitutes for horses, from their greater facility in feeding. Goats have nearly disappeared ; and the few that are yet to be seen appertain generally to wealthy tenants, rather as objects of variety or of amusement than profit. The neglect of swme appears a radical defect in the farming systems of this country, since the sea shores and the unlimited power of cultivating potatoes would render them a valuable stock. I may also add, that rabbits are absolutely unknown ; a neglect which is very striking, since innumerable insular situations, capable of being converted into warrens without expense, would render them objects of profit in the commerce of peltry, as well as a welcome addition to the meagre and limited catalogue of a Highland tenant's food. TIREY. GEOLOGY. 45 There are few things more remarkable to a stranger who has been accustomed to the cottages of the south, than the total want of gardens, or even of any culti- vated vegetable beyond the potatoe. It is not an ex- aggeration, I believe, to say, that there is not a culinary vegetable in the country except in the establishments of the proprietors and principal farmers, nor are even all these exempt from censure for their neglect of this department of rural economy. The facility with which this most simple improvement might be introduced, and its total absence, seem unaccountable : but it is disagree- able to proceed where there is more to censure than to praise ; I shall therefore terminate this digression, and return to the geological structure of Tirey. Taken in a general view, the whole chain of Coll and Tirey may be said to consist of a body of gneiss. But each island offers sufficient varieties to render a more minute description necessary. I was unable in Tirey to trace any regularity of dis- position, or even such an approach to it, as to lay down the probable course of tlie beds. This may arise in a great measure from the inconsiderable elevations of the rocks above the plain, but it is scarcely visible even in the hills ; or if for a small space any line of direction or any inclination of a few beds is traced, at the very next step the order ceases, and the appearance of regularity vanishes. Considerable masses of naked rock are seen in the small hills above described ; but except in one place there is no precipitous face, the general character consisting in summits of detached ridges separated by patches of grass. In the flatter parts of the island similar protuberances are irregularly dispersed all over the soil, seldom ex- ceeding from ten to twenty feet in height. The peculiar external forms of gneiss are obvious throughout the 46 TIREY. GEOLOGY. whole country ; but the conckision resjiecting its univer- saHty is not deduced from a general view only, portions having been examined from one extremity of the island to the other. . It is possible that some beds of the other rocks which occur in gneiss may have escaped my observation, but this must ever happen, as no length of time would suffice for the fracture and examination of every rock which protrudes over a surface of this nature and extent. Under the gray crust of lichen, which wraps all in one undistinguishable covering, mineralogical treasures may yet be concealed in Tirey as in many other places. The composition of this gneiss is various, but the varieties are all included in that division of it which also forms lona. Generally speaking, it is characterized by the presence of hornblende. Mica is more rare ; and although it is found even together with the hornblende, it is most generally observed in the vicinity of the granite veins by which the gneiss is traversed. The prevailing compos^ ition therefore is hornblende, quartz, and felspar. In some places it is very perfectly foliated, in others it approaches so near to granite, that its nature can only be discovered by a favourable fracture. The quartz occasionally disappears, in which case the rock sometimes puts on an appearance intermediate between gneiss and granite ; which gradually passes, by varying into a finer grain, or by the exclusion of more of the felspar, into a simple hornblende schist, or into that mixture of hornblende and felspar which has been called primitive greenstone ; in some cases to a mere unfoliated hornblende rock. It is also not uncommon to find in it larger or smaller laminae, or beds and lumps of horn- blende rock. There is no regular progress from the granitic to the schistose beds, but they seem to be every where mixed, without order or arrangement. The varieties in which hornblende predominates appear however more abundant at the southern end of the island, 2 TIREY. GEOLOGY. 47 in Ben Hynish and Ben Hinivarr, and the paler ones at the other. In many cases these pale varieties consist almost entirely of felspar, or of felspar and quartz ; just so much hornblende entering into them as to give the linear appearance by which in a particular direction gneiss is always to be distinguished, and which forms in these cases its only ground of distinc- tion from granite. Wherever the gneiss is visible, of whatever composition it may be, it is almost always more or less contorted or bent. Very rarely can a few yards together be seen, of which the laminae are straight as well as parallel. Yet, however disturbed, there is always an indication of the laminar structure in some part or other of the mass. This gneiss abounds in granite veins, and there is great difficulty in ascertaining their forms. In many cases they obviously run a long and determined course, giving off lateral ramifications, and being accompanied by visible shifts in the continuity of the beds of gneiss which they traverse. In others they present irregular lumps of different sizes, sometimes ramifying, sometimes simple, but still attended with a confusion of the gneiss in which they lie. They are often as abundant as the rock which they traverse ; in many cases they even occupy more space, fragments alone of the gneiss ap- pearing among the intricacies of the granite. At times they intersect each other so as even to produce a reticu- lation of the general surface, their intersections being sometimes attended Avith the shifting of one of the veins ; while at other times they cross each other without any change of direction in either. They differ somewhat in composition, and it is one of their frequent characteristics to contain larger concretions of one or other, or of all their several ingredients, than ordinary massive granite. In other instances, they are of so common a character, that specimens taken from them would not be sus- 48 TIREY. GEOLOGY. pected of liaving been derived from veins. Wlien the felspar is large it has most usually a glassy aspect ; occasionally it is of a brick-red colour, as are also many of the granitic varieties of the gneiss. These redder varieties are most abundant on the w^est side near Bal- phetrish, and in the vicinity of Cornag more. In the gneiss there occurs a singular rock, consisting of quartz with imbedded crystals of felspar : but as it is more common in Coll, I shall delay the description of it for the present. The granite of the veins contains in general the four ingredients, quartz, felspar, mica, and hornblende. Green compact felspar, although much rarer than in lona, is nevertheless found in it. In the vicinity of Trava bay I also observed the same ingredient entering the gneiss, thus forming a beautiful rock consisting of alternate laminae of this substance, and of common felspar mixed with hornblende. In one or two places there occurred among the veins specimens worthy of notice for the colours of the felspar and of the quartz which they contained. In one of these the felspar was of a pale indigo blue and of a glassy lustre. In the other the quartz was of a sea green and considerably translucent. In both cases these sub- stances were in small concretions. The gneiss of Tirey is more remarkable for contain- ing masses of limestone. One of these has long been known by the flesh-coloured marble which it affords ; of which a quantity has been exported for the purpose of ornamental architecture since the time when it was first pointed out by Raspe. It is improperly called a bed, as it is only an irregular rock, lying among the gneiss without stratification or continuity. In this respect it resembles the greater number of the primary lime- stones found in gneiss and in mica slate, and may be considered as a large nodule. There is considerable obscurity attending these detached masses of limestone. Of all the rocks which occur in extended masses, granite, TIREY.' — GEOLOGY. 49 trap, and porphyry, only, are unstratified ; while the others possess characters of stratification almost always very un- equivocal, although in many cases attended with marks of posterior derangement. It is possible that the masses of limestone thus found in gneiss have once been stratified, and that they have suffered some posterior changes by which the appearances of this disposition have been obli- terated. In illustration of this opinion I may point out the state of the white marble of Sky, hereafter described ; which, though at present as shapeless as the limestones in question, has been once undoubtedly stratified, since it forms portions of a series of parallel strata containing organic remains. Similar illustrations may be drawn from the nature of the limestone in the Isle of Man, which I have described elsewhere; as well as from many well known rocks of this family, which, although now without the slightest mark of stratification, give indications of their having been originally thus formed, from their containing, like those of Sky, organic fossils. The nodule of limestone which constitutes the marble of Tirey under review, appears to be an irregular mass of about 100 feet in diameter, and is surrounded on all sides by gneiss. The contact is always very defi- nite, yet the quartz seems to be the substance most gene- rally in union with the limestone. Notwithstanding this defined contact, it occasionally contains imbedded lumps of granite or gneiss similar to those which occur in the limestone of Glen Tilt. These are always visible at the surface, from their superior power of resisting the action of the atmosphere. This hmestone is of a reddish hue, varying from a high flesh-colour through pink to nearly white, and from a muddy crimson to a dull purple ; often also with a greyish aspect bordering on blue. It is of a very fine splintery fracture and smooth grain, precisely like the marble of lona. Though no where bedded, nor capable of being raised in parallel-sided masses, yet after exposure to weather it not unfrequently splits into VOL. I. E 50 TIREY. GEOLOGY. thin laminae with great facihty, marking a structure once probably stratified. It contains occasionally large con- cretions of black and shininsf hornblende, of two inches or more in length, but is most distinguished by the quan- tity of augite dispersed through it, to which its beauty, as an ornamental marble, is principally owing. The effect arises from the contrast of the dark green spots with the reddish tone of the ground. In consequence of its hard- ness it has fallen into disuse, although, even under that inconvenience, it is still cheaper than many foreign marbles of far inferior beauty*. The quarry has been ill wrought, and indeed nearly ruined by gunpowder, having been managed apparently by workmen ignorant of the use of the feather-wedge or other modes of raising unstratified rocks. About half of it seems to remain untouched; but much even of that is split by the mines used in detaching the blocks which have been quarried. Not far from the house of Balphetrish, and in the vici- nity of the rock now described, another considerable mass of limestone occurs. It is equally irregular, but of ten times the size of the former, and like that, bounded on all sides by gneiss. It has been quarried, apparently for the sole purpose of building dykes, at least I could not hear that it had been used for the purposes of ornament. It bears a considerable resemblance to the former in composition, but contains many more varieties of the py- roxene by which that is characterized. The basis of this marble is white. When pure, it is equally snowy in aspect with the marble of lona, which it also resembles in texture and fracture, except that it has no where a schistose tendency. In most parts, however, it is impure, even where it contains no imbedded mineral ; breaking * Such has generally been the public caprice with regard to our na- tive productions that scarcely an ornament exists in Britain of the beauti- ful serpentine of Portsoy, although in the reigns of James the Fifth and Mary it was wrought and exported to Paris, where specimens of it may now be seen among the interior architecture of many houses. TIllEY. — GEOLOGY. 51 with a large irregular fracture, and showing greenish yel- low stains in the natural rifts. This seems to arise from an admixture of serpentine or steatite. The same substance is found dispersed through it, either in small lumps or in minute grains of a dark green or yellowish hue ; the specimens differing in no respect from the well known pebbles of similar marble which are found in lona. This variety is highly ornamental, but there does not appear to be any extent of it applicable to useful purposes. The variety which con- tains sahlite seems to be considerably more abundant, This mineral is dispersed in the form of small grains, like the coccolite of the pink marble, through a pure white calcareous ground, the crystals being in general thinly disseminated, and of a pale, or hght blueish, or dark greenish grey colour. These grains are also at times crowded together in detached lumps of the size of a nut, and from that to the size of an orange, or larger. Where the surfaces have been exposed to the weather they are readily seen ; not so much by their own superior perma- nence, as by that of a nodule of the marble immediately surrounding them, which is always much tougher and harder than the general body of the rock. The last calcareous rock which I observed in Tirey is in Gott Bay. This is a blueish limestone containing much mica, and of a very tough constitution. It forms a nearly vertical set of irregular beds of no great extent, accom- panied by gneiss and traversed by granite veins ; in which latter circumstance it differs from the calcareous rocks before described. These veins may be traced passing from the gneiss into the limestone. The action of the sea having deeply corroded the upper edges of the beds, has brought to light an intricate con- tortion which they seem to have undergone. This it has effected by acting on the micaceous laminse, thus separating the flexuose calcareous strata by deep erosions, There is a great resemblance between the contortions of 52 TIREY. GEOLOGY. these beds and those of the Hniestone of Glen Tilt ; and in both cases granite is present. The contortion of beds is a phenomenon of much interest in geology. Although common in the schistose rocks, it is of more rare occur- rence in limestone, and therefore worthy of being pointed out wherever it exists. It appears to be so obvious a consequence of the posterior disturbances of beds in a softened state, that it is unnecessary to accumulate argu- ments on the subject. In Mar, in Glen Tilt, and in this place, it is either accompanied by the presence of granite veins or occurs in the neighbourhood of granite masses. In many cases the disturbances of the schistose rocks also occur mider the same circumstances ; but there are never- theless instances every where of great contortions in all these rocks where granite has not been found in the neighbourhood. It would be generalizing without just grounds therefore, to say that the disturbances of these rocks were produced by the vicinity of granite. Many other causes of motion besides the supposed protru- sion of granite may have existed among the strata which constitute the surface ; but of these our imperfect know- ledge prevents us at present from forming any judgment. The phenomenon in Gott Bay now described is of some importance in the history of gneiss. It has been said that all the granite veins in gneiss are contemporaneous ; a term of which the meaning is not always very definite. In this case it is perhaps meant, that the granite vein is a necessary portion of the gneiss ; each being formed in- dependently of the other, although in a state of contact and mixture, and the appearance of a vein being merely incidental. But in the rock under consideration the same body of granite which traverses a bed of gneiss, traverses an approximate bed of limestone, without change of direction, continuity, magnitude, or cha- racter : a phenomenon possessing on this supposition the highest degree of improbability, and requiring circum- stances of which we can form no conception. TIllEY. MINERALS. 53 I must now proceed to describe at more length the mineral substances contained in the rocks of Tirey ; the most conspicuous of which are those at present ranked under the general term of pyroxene. All these, as must already have appeared, are contained in the different limestones ; the darker coloured, which possess the characters of augit, being found in the pink lime- stone, and the several varieties of sahlite in the white. I have pointed out in different parts of this book the predominance of augit in Rum, in the Shiant isles, in Sky, and in Arran ; it occurs also in other places, but always as a constituent of the trap rocks. In Tirey alone, as far as I have observed, it is found in primary limestone. Sahlite is found in a more dispersed manner and in smaller quantities ; but it occurs in several places, as in Harris and in Glen Elg, affording different varieties, and gene- rally, as it is here, accompanied by tremolite and forming- large nodules in primary limestone. In Rannoch I have also found it imbedded in a primary micaceous limestone, in distinct crystals, resembling those specimens found at the Lake Baikal. In this place it is accompanied by quartz, titanite, and oxidulous iron. In Glen Tilt it forms distinct beds in the primary limestone, and in this situa- tion also it is accompanied by tremolite. The augit which occurs in the pink marble of Tirey sometimes pre- sents large, distinct, imbedded crystals, an inch in length, of a dark green or nearly black colour. These resist de- composition longer than the limestone, and are conse- quently found protruding from its surface when that has been exposed to the weather. In some places it forms shapeless masses, while in others it appears diffused through and intimately mixed with the calcareous matter ; in which case, like the distinct nodules, it is often attended by an investing zone of greater hardness than the general mass of the rock. But its most common ap- pearance is that in which it is generally known as forming a constituent part of the marble ; in this state 54 TIREY. — MINERALS. it is the coccolite of mineralogists. The crystals are occasionally defined ; but most commonly they are either partially rounded or entirely shapeless, forming irregular grains sparingly dispersed or accumulated in larger or smaller groups. These accumulations are sometimes very considerable in size, and admit of being detached in large and well characterized specimens, the grains varying much in colour, being black, dark bottle-green, blueish green, and pale grey. The sahlite presents many varieties both of form and colour, and is either compact or crystallized. In colour it is snow white and opake, or white and glassy; from which it passes into several shades of grey and green, and more rarely into pale sky-blue ; presenting several intermediate gradations from opacity to absolute tran- sparency. The crystals appear under different forms. The most perfect is a slightly rhomboidal prism, which is sometimes truncated on all the edoes, the truncations in- creasing in breadth till an octagonal prism with nearly equal faces is produced. In other instances the trunca- tions are limited to two edges, in which case an hexaedral prism is the result. This prism is often much flattened, and at times quite thin, the two truncated edges extend- ing till the original faces are nearly excluded. Some crystals present a very flat tetraedral prism, but as they are much imbedded and difficult to examine it is not easy to ascertain how this variety is produced. The faces of the flat prisms are sometimes rounded, and this con- vexity occasionally extends to the faces of the summits also, so as to produce a very irregular body. In this state it shows the transition into coccolite, that point at which all form vanishes ; the appearance of these curved surfaces resembling that which might be conceived to take place from an incipient solution of a regular crystal ; as if the angles had been rounded off into the neighbour- ing planes. The terminations of the crystals, when perfect, are, in their most simple state, tetraedral pyramids. TIREY. MINERALS. 55 Their summits are sometimes truncated, but no further regular modifications of this part of the crystal were observed. A regular transition occurs between the sahlite thus described and coccolite, exactly similar to that which takes place in the augit; and masses of coccolite are thus found of considerable size and of different co- lours. The most remarkable of these is snow white and opake, forming a new and beautiful variety of this sub- stance. From this it passes into various shades of grey, equally loose in texture, and falling into distinct grains when injured. The specific gravities of these several varieties are nearly the same ; and it is remarkable that the whitest varieties which seem to contain no metallic matter, are equal in weight to the darkest, which con- tain so large a proportion of iron. The sahlite, as I have already mentioned, is frequently accompanied by tremolite. The crystals of both sub- stances are often intermingled and confounded together, or a crystal of the former penetrates and mixes with one of the latter in so intimate a manner, that as the two sub- stances have frequently the same colour and splendour, it is not easy to distinguish them. In one of the spe- cimens found, a crystal is divided longitudinally, the one half being of tremolite the other of sahhte. The tremolite presents a very beautiful variety ; forming groups of separate crystals, which are in the usual shape of very flat rhomboidal prisms, interwoven together in a distinct manner and with large cavities interposed ; the crystals being two inches in length and three quarters of an inch in breadth. In texture it is glassy, and being translucent or nearly transparent, is of a watery white. Mica is found intermixed with the sahlite, in small crystals of a talcose aspect; and it occurs in a similar state in the limestone of Glen Elg, accompanying the two mi- nerals above mentioned. The last mineral to be noticed is sphene, which is S6 TIREY. MINERALS. found in the pink marble, the crystals being minute, rare, and not easily discovered*. * It has been said that corundum was formerly found in Tirey, but no specimens of it have been produced. As the several varieties of pyroxene, with the exception of the coccolite imbedded in the pink marble, had then been overlooked, it is not unlikely that some of these have been mistaken for this substance. It appears also that the blue variety of sahlite has been recently mistaken for hauyne. COLL. — GENERAL DESCRIPTION. 57 COLL.* The dimensions of Coll are very similar to those of Tirey, its extreme length being about twelve miles and its mean breadth somewhat less than three. In the general outline of the coast it also resembles that island, although the extent of the rocky shores is perhaps greater in proportion to that of the sandy bays. It differs, however, materially in its general aspect and surface, being so much covered with rocky hills and protuberances as scarcely any where to exhibit a con- tinuous level, or grassy plain. Towards the northern end of the island these indeed abound to such a degree, that when viewed from a low point of sight, it seems to present but one entire surface of rocks. Notwithstanding this aspect of barrenness it is interspersed with green spots of greater or less magnitude, which are estimated to comprise, in arable, meadow, and pasture land, about one third of its extent. Towards the southern end there is a considerable tract of unencumbered land, the rocky elevations being here more sparingly dispersed and this side of the island approaching more nearly in its general character to the neighbouring parts of Tirey. Patches of sand are interspersed among the verdant soil in this quarter, and more particularly toward the southern and western shores, where, in some places, it has so far accu- mulated as to overwhelm and destroy considerable tracts. These accumulations are occasionally thrown up into irregular banks and hills, as is usual in similar cases, being again dispersed by the winds as they succeed in destroying the feeble protection which the Carex arenaria, Triticum junceum, and other plants indigenous to blown * Coll, a hazel ; coil, a wood ; Gaelic. If this be the etymology, the character of the island is much changed since the name was imposed. See the general map. 58 COLL. GENERAL DESCRIPTION. sands, afford against their violence. It is not long since the utihty of these plants has been known to the natives, and it is with some difficulty that they are even now restrained by the more enhghtened proprietors throughout the islands from destroying them, and thus accelerating the progress of this wasting inundation. The use of the Galium verum as a dye, is the chief inducement to this pernicious practice. The sand consists in a great measure of broken shells, mixed, however, with the quartz which arises from the decomposition of the gneiss. Being thrown on the shore by the prevalence of the western swell, it is dried by the winds and dispersed by a gradual progress into the more inland parts. Thus, in particular places, and in proportion to the obstacles it encounters, it forms banks and sand hills ; or else is dif- fused over the flatter tracts, where the renewal of vegeta- tion tends to consolidate and retain it, thus perma- nently raising their level. In other situations it pro- duces a soil on the naked rocks, accumulating in their sheltered interstices and forming a basis for a vegetation to be ultimately extended; while it operates as a constant manure to the peaty tracts within its reach, loosening the tenacious soil and promoting the vegetation of white clover and other useful plants, in place of the scanty covering of rushes and useless vegetables with which they were before encumbered. Thus, like manures, it is injurious only by excess, and in recording its devasta- tions, it is but justice to describe its beneficial properties*. The plants which cover the sandy plains of Tirey * To the other advantages derived.from the sand inundation it may be added, that it often produces valuable and permanent additions to the extent of the islands exposed to its influence. A great part of Tirey appears to be of no very distant origin, having been formed by its accumulation on a ledge of low rocks extending between the hills that occupy the extremities of this island. The traditions which record the recent existence of salt water inundations in its central parts confirm this opinion » COLL. GENERAL DESCRIPTION. 59 abound here also, perfuming the air around, and in the season of flowering, prevaihng so as to conceal the verdure from the eye. A small tract, known by the name of the variegated plain, presents an enamelled carpet of unde- scribable gayety, being covered with all the ordinary meadow plants, together with a profusion of the brilliant crimson flowers of Geranium sanguineum. Spring has here ' a character no less remarkable for its novelty than its splendour. Although protracted till late in June, and though no trees are seen bursting into leaf, the colours which deck the ground, the perfume that fills the air, and the melodious note of the wood-lark, produce an effect, striking both in itself and in its contrast with the desert of rocks and the wide ocean which every where meet the eye. Besides the plants just mentioned, a few others, less common, are met with in profusion through- out the island. These are, Thalictrum minus, Ophrys ovata, Satyrium hircinum. Orchis conopsea. Orchis mascu- la, Sedum anglicum, Rosa spinosissima. Crambe raaritima occurs also in abundance along the sandy shores on the western side, and the beautiful Osmunda regalis is found abundantly in the interior and moister parts of the island, while the small lakes are covered with the brilliant flowers of Nymphoea alba, and the less conspicuous Potomogeton heterophyllum. Coll, however, cannot be said, any more than Tirey or the other islands of these seas, to possess many plants remarkable for their rarity. But the Erio- caulon decangulare, hitherto found only in Sky, forms an exception to this remark, growing in some of the central lakes in company with Lobelia dortmanna, and attaining a much larger size than it exhibits in that island. In the agriculture of Coll there is little to be remarked, if we except some superiority of management arising from the example and knowledge of the proprietor, which would not be a repetition of what has already been said on 60 COLL. GENERAL DESCRIPTION. this subject in describing Tirey. Barley, to which the sandy soil is best adapted, is here the principal grain, oats being less in nse ; rye is sparingly cultivated, but with indifferent success. The chief cultivation is found at the southern end of the island, where there are uninter- rupted tracts of even land ; while among the more rocky spots towards the middle and northern divisions, the crops are seen occupying small patches and single ridges in a dispersed manner. The middle parts of Coll contain numerous small lakes, rarely of any great depth ; together with accumu- lations of water scarcely deserving of that name, and occasional marshy spots. The lakes are said to amount to forty in number. Like Tirey, nevertheless, it is defi- cient in running water, scarcely a spring or a stream being found in it, although water may often be procured near the surface by digging. This defect, which is attended with much occasional inconvenience, must be attributed partly to the small elevation of the land, partly to the nature of the rock, and still more perhaps to the climate, which, though far advanced in the western ocean, is dry ; the clouds passing unchecked over this as they do over most of the flat islands of these seas. To the lover of the picturesque. Coll, like Tirey, oifers no scenes to engage attention. The hills are without elevation or variety, while no plant taller than heath grows on them. A turbulent sea breaks on a shore with- out features, and the distant boundary is almost every where the line of the horizon. The castle is a rude building, situated on the sea shore in a position disadvan- tageous for effect, without character, interest, or accom- paniments to give it a value in the painter's eye ; and the Danish forts, as they are called, which are found in various parts of the island, have little remaining beyond their names to mark the places which they once occupied. COLL. — GEOLOGY. 6\ There are some differences between the geological fea- tures of Coll and Tirey, although gneiss constitutes the mass of this island also from one extremity to the other. No limestone, an object always of great research for agricultural purposes, has yet been observed, although it is not improbable that among the thousands of grey rocks which cover its surface, some calcareous beds or masses may yet be latent under the covering of grass, heath, and lichens. The gneiss is disposed in rocky hills, sometimes crowd- ed, at others distinct, of an elevation seldom or never attaining 500 feet, interspersed with smaller protuberances, and extending over the whole surface of the island. Towards the southern and western parts it exhibits in many places a regular disposition in beds, of which the alignment can often be traced for a considerable space, straight, and free from all that disturbance which marks the rocks of Tirey. Towards the middle and the nor- thern end of the island this order is not so visible, the masses appearing to be disposed in an irregular and dislo- cated manner. The direction of the beds, where it can be traced, is north-easterly, and their dip is toward the east. Their elevation is generally considerable, often reaching to seventy or even to eighty degrees, and seldom de- clining so low as to fifteen. The mineral composition of the regular and irregular beds is not essentially distinct, though their external aspect differs : hornblende is found in all, as in Tirey. The laminar structure is sometimes evanescent ; in which cases the rock borders so nearly on granite as to be scarcely distinguishable from it. In other places it passes at one extreme into hornblende schist or into an ordinary hornblende rock, while at the other, by the exclusion of the quartz and hornblende, it becomes merely a mass of felspar. Between these two there are seen numerous and nameless varieties, differing both in texture and composition. But it is most usual to find 62 COLL. — GEOLOGY. specimens variously proportioned with regard to their ingredients succeeding each other in parallel and alter- nating laminse : and since mica is often superadded to the triple compound of felspar, quartz, and hornblende, the various ways in which this mineral is disposed tends still further to increase the number of varieties. Although the gneiss which is irregularly disposed, resembles in composition that which displays a parallel position and rectilinear direction, it is distin- guished by some important peculiarities. It is every where traversed by innumerable small reticulating veins of granite, a circumstance so well known as a frequent characteristic of gneiss, as to need no further de- scription. It exhibits at the same time the most capricious contortions. These reticulating veins occur but rarely in that gneiss which is disposed in a regular manner ; or rather they are almost altogether absent. Instead of them there are to be observed in this variety of the rock, granitic laminee, which are parallel to the position of the beds and of course alternate with the real gneiss. They are easily distinguished by the total absence of foliated tendency : in hand specimens no ques- tion would remain respecting their place among the granites. In many cases, however far they are traced, they still appear to be uniformly parallel to the gneiss and to avoid any interference with it ; while in others the parallelism is but temporary and they at length quit their even course, becoming either thicker or thinner, or cutting in upon the course of the laminse. Hence, although we might, from the instances first quoted, conceive them to be regular beds of granite alternating with the gneiss, the occurrence of even one deviation of this nature is sufficient to prove that they are disposed in veins, of which the directions are parallel to its laminae. It is easy to understand why the parallelism of the gneiss is preserved where it is traversed by veins of this nature, while its evenness is interrupted and COLL. — GEOLOGY. 63 contortions produced in the beds, where their course is irregular or transverse. The smaller granite veins, whether parallel or transverse, have most generally a fine grained structure with the aspect of an ordinary granite, although this rule is far from absolute. But both the regular and the irregular gneiss are tra- versed by larger veins which produce an occa- sional disturbance in each. In the irregular they only add a little to the general confusion, and even in the regular beds they seldom produce so much displace- ment as materially to divert them from their general tendency, unless where they are very numerous. These veins have almost always a peculiar aspect, containing a large proportion of felspar with but little quartz, the mica being also either sparingly dispersed or altogether absent. The concretions of felspar are often of great size, the substance itself having a high glassy lustre : the veins also frequently assume the graphic character. Towards the southern end of Coll veins of similar dimen- sions occur among the gneiss, disposed in the same man- ner, but formed of a peculiar rock, which I slightly men- tioned in describing Tirey. The basis of this substance is a quartz possessing considerable transparency and an oily lustre, and containing crystals of red felspar thinly disseminated. Similar compound occurs in the gneiss of Sky. There remain still to be described two circumstances which are important towards the general history of gneiss. Distinct beds of mica slate are found regularly alternating with it in several places. A still more re- markable appearance is that of a bed similarly situated and consisting of a conglomerated rock formed of frag- ments of quartz imbedded in a micaceous schist ; offering an example of a breccia in a situation where these have not been supposed to exist. This rock is to be seen in a small bay near Ben Feoul. It is unnecessary, after the remarks on that subject in 2 64 COLL. MINERALS. describing Tirey, to renew the question respecting the contemporaneous nature of the granite veins of gneiss. But it is quite obvious throughout Coll, wherever the beds possess sufficient regularity to render that circumstance perceptible, that they are shifted by the passage of those veins. I have given two examples of this nature in a diagram*. An equally remarkable instance of apparently mechani- cal arrangement occurs at the southern end of the island, of which there is also a representation subjoined f. Analogous appearances must be familiar to all those who have had opportunities of examining rocks of this nature ; but the present example is interesting chiefly on account of its magnitude and of the apparent instance of softening and flexion which it affords. The nodules of hornblende rock here represented are of considerable size, attaining a diameter of three or four inches, and the laminae of gneiss are every where bent over them, as if they had, when in a soft state, been forced by external pressure to accommodate themselves to the previously indurated concretions. Such are the principal geological features of the gneiss of Coll. I shall not here attempt to draw any further general conclusions from the appearances which have been described, since a considerable tract of the same rock re- mains to be examined. If any useful views are to be de- duced from the comparison of facts, they will be more easily and more certainly established when a greater body of materials shall have been accumulated. Since mica is an ingredient of gneiss, it cannot strictly be considered an adventitious mineral ; yet it is here found in concretions so large as to require notice among the mineral substances to be enumerated. It is always black, at times crystallized, and in other cases disposed in large plates without definite forms. It is very often mixed * PI. xi. tig. 1,2. t ri. xxvi, fig. 1. COLL. — MINERALS. 65 with hornblende in such a manner that it is difficult to dis- tinguish one ingredient from the other. This is particularly the case where the specimens are broken by a cross fracture, the micaceous ingredient being scarcely visible unless when the rock is split in the direction of its laminae. it is hardly necessary to say that hornblende in a dis- tinct state is also found in this gneiss, since it must already have appeared from the description of that rock, in which beds of hornblende schist and hornblende rock are mentioned as occurring. This hornblende is black and of the most usual aspect, and is occasionally found in the form of aggregated crystals of large size, offering a beautiful variety for the collectors of mineral specimens. This mineral occurs also in Coll under a different aspect, but much more rarely, since I only observed it in the neighbourhood of Ben Feoul. It is of a platy fracture and bottle-green colour, with a lustre approaching to the metallic, being little less splendent than hypersthene or diallage, with the latter of which it may easily be con- founded. I may add that similar specimens of hornblende are occasionally found in mineral collections arranged under this title. This substance is found entering into the composit'on of a rock of which the other consti- tuents are common black hornblende and black mica ; being sometimes mixed throughout the mass, and at others forming large and distinct concretions. At times also, quartz as well as felspar enter into its composition, and the compound presents in this way various specimens of con- siderable beauty. The rock itself constitutes a bed alter- nating with the ordinary gneiss. I may further add to this enumeration of the varieties of hornblende, that a lamellar and green kind much intermixed with pyrites is found forming a rock in the same neighbourhood. This variety does not possess the metallic lustre which •characterizes the former. Actinolite is also found in Coll. It is of a bright green colour and of a lamellar structure, forming in some VOL. I. F ' 66 COLL. MINERALS. cases a constituent part of tlie gneiss, while at the same time it may be observed in the state of distinct concretions dispersed throughout the beds. In such instances it sometimes occupies cavities, and is then regularly crystal- lized. It occurs in the same manner in a kind of quartz rock which appears to alternate with the gneiss, but which was not described in speaking of the other alter- nating substances, because from its inaccessible position I could not pronounce decisively respecting it. Both these rocks are remarkable as well for their peculiarity as for their beauty, when considered as mineral specimens. A bed occurs among the gneiss at the foot of Ben Feoul, of a singular aspect, but appearing to be prin- cipally composed of actinolite under some modifica- tion. It is of a confused lamellar structure, the lamellae having a tendency to the fibrous fracture, and being of a dull purplish brown colour. On a nearer exa- mination it is found to contain interspersed crystals of the green lamellar actinolite which occurs in the gneiss above described. The brown part which constitutes the main body of the rock, is opake and dull, but possesses in every other respect the characters of the green part ; and a perfect idea of it may perhaps be formed by imagin- ing it to be the same substance overcharged with an oxide of iron, just as quartz sometimes is with chlorite or calca- reous spar with sand. Garnets are found in the gneiss, here as in many other places, but they are neither abundant nor well defined, being at 'the same time confined to those lamina which possess the most granitic aspect and structure. Massive brown garnet is also found in large irregular lumps, dif- fused, as it were, through the rock. Independently of the more common forms in which quartz here appears, it occurs also under some of its less frequent modifications ; these, as far as I have ob- served in Scotland, seeming to be always limited to gneiss. The most remarkable example is to be seen COLL. — MINERALS, 67 on the face of ti rock not far from the house of Coll, where it appears to form part of a vein of which the side has been exposed by the falling down of a bed of the gneiss by which it was bounded. Its aspect is often waxy, an appear- ance very common in the quartz veins that traverse gneiss, while at times it assumes a character resembling that of chalcedony. The structure is generally lamellar, and it is traversed by fibres or strings of a whiter colour and of greater opacity. On exposure to air it becomes dry and harsh, losing much of its transparency. Where it possesses the greatest degree of transparency it is opalescent, being the milk quartz of mineralogists, and either exhibiting a whitish and diluted milky hue, or a tinge of blue, purple, or pink. These latter specimens resemble the well known rose quartz, but are rarely of sufficient magnitude, purity, or intensity of colour, to possess much value in the esteem of a collector. Felspar also occurs in great variety and beauty, appear- ing, like quartz, to be subject to more numerous modifica- tions as a constituent of gneiss, than when it enters into the composition of granite. It is found in large concre- tions, sometimes occupying the granitic laminae of the gneiss, and at others the veins of graphic granite. Its colours are various, being white, red, brown, and grey, the specimens having often a pearly aspect and sometimes a glassy and splendent fracture. The gra- phic granite which contains these glassy varieties is often exceedingly beautiful, and as lichens rarely find a lodgment on its surface, it dazzles the eyes when in the sunshine by the play of reflected lights. It is worthy of remark to mineralogists, that in these cases the incident rays are reflected to the spectator's eye from a great extent of surface, although that is often very irregular. The reason is obvious, this effect resulting from the dis- position of all the reflecting faces being parallel, how- ever distant and minute they may be, and however sepa- rated from each other by the intervening quartz which 68 COLL. MINERALS. forms the remaining part of the mass. We may either consider this parallel disposition as the result of a common polarity or crystalline tendency in all the minute portions of felspar which are aggregated to form the vein, or may suppose that the whole mass of rock is a portion of one crystal of felspar, interrupted by intervening crystallizations of quartz. Similar arrangements arising from a common polarity among distinct crystals are not uncommon, and must have occurred to all mineralogists. Cases perfectly resembling this are of frequent occurrence in augit rock, and are noticed in different parts of this work. They occur also in the sandstone of Arran, described in another place. Among minerals I have observed it most frequently where mesotype and needlestone are associated with stilbite and analcime, the former substances main- taining their rectilinear course without regard to the inter- ruptions caused by the latter. In one remarkable instance in my possession, where detached tabular crystals of oxidu- lous iron occupy the surface of a mass of rock, they are disposed in those curves which indicate the directions of the magnetic current between the two poles of the needle : an interesting point of resemblance between the effects of magnetic and crystalline polarity. A vein of lead ore has long been knov/n in Coll. It is a narrow string of steel-grained galena lying in a fissure of the gneiss and terminating in the sea. This fissure forms an angle of about 20° with the course of the beds. The ore is not accompanied, as far as it is visible, by any other substance, and, offering no prospect of profit, it has not been wrought. I have deferred to the last place the mention of augit, because, not having found it in situ, I am in doubt whe- ther it may not be a transported rock. The specimen in question was a single block, and being at a great distance from the shore there is no reason to think that it had been brought in ballast. Otherwise it might be imagined to have belonged to the Island of Rum, of which that substance COLL. MINERALS. 69 forms a large portion. Yet there are no rocks of the trap family in this island, if we except veins, to justify the notion that it is in its native place. These veins are by no means common, but they may be seen in different places. Their dimensions, as far as I observed them, do not exceed four or five feet, and they are formed of a black compact basalt. They are often characterized by a tendency to the columnar fracture, and do not seem materially to disturb or influence the rocks which they traverse. 70 BARRA. — GKNERAL DESCRIPTION. BARRA.' This islandf is of a very irregular and indented shape, containing but a small surface compared with its extreme dimensions, which are ten miles in length, by seven m breadth. If indeed the hill above Kilbar be considered only as an appendage, its length will be reduced to seven miles. This appendage of Barra consists of a single hill, connected with the remainder of the island by a flat sand, over which the western and eastern seas almost meet at high water. They have probably been at one time sepa- rate islands, subsequently united by the sandy isthmus which the action of the waters has thrown up; nor is it impossible that in some of the revolutions to which these shores seem exposed they may again be separated. To- ward the southern and western side of the island arises one high hill scarcely attaining the height of 2000 feet, descending to Chisamil Bay and declining to the north and east in a succession of lower hills which terminate in various rocky points on the shores. The intervals of these rocky promontories are occupied by sandy bays communicating with small valleys in which the popula- tion is accumulated. These valleys presenta soil composed of * Bar-ey — The island of Saint Bar; probably its apostle. — I must here remark once for all that the orthograpliy of tiiese names is variable, such variations having probably arisen from the marked dilVerence be- tween the Gaelic orthography and pronunciation. In this particular instance however, the terminal syllabic is not Gaelic, but Scandinavian. Ey, for eyland, island ; hence the termination by which many of these islands are distinguisiied, its orthography having nevertheless in process of time been generally corrupted into the terminal a. Thus, Caima, Rona, Vatersa, Sandera : in some few the terminal is spelt ay, and in Tirey it continues unchanged. f It is proper here to say that the whole ot" the westernmost cliain froin the Butt of the Lewis to Baira Head is known to the natives by the name of the J. ong island; .'i term which I have often found it convenient ty U50. See the general Map, EAllRA. FISH Kin F.S. 71 a mixture of peat and sand, and near tlie shores, of sand only ; while the hills offer nothing to the eye but a motley mixture of peat and rocks, affording but scanty pasture to the black cattle which form the chief agricultural wealth of the island. The rocky shores abound with fish, principally ling,; in fbe pursuit of which the inhabitants are very industrious. When cured they are carried by the fishermen themselves to Greenock, and in this way much time is unprofitably occupied ; an evil, which a greater extension of the fishery and a proper commercial arrangement would easily remedy. But society here is not yet advanced to the state that admits of those arrangements; and to this want is in part owing the very inadequate manner in which fishing is con- ducted along many parts of this productive shore. The impediments arising from the want of commercial arrange- ments, and tlie deficiency of capital, are not, however, universal in the maritime Highlands ; as establishments under the direction of capitalists, exist in various parts of the western coast, and are followed by the results that might naturally be anticipated. To the preceding causes must be added the difficulty of reconciling the often incompatible pursuits of farming and fishing ; the most active season of the fishery being frequently that where the attention of the fisherman is also required at home, to conduct the operations of agriculture, on which he must still depend for the chief part of his subsistence. It is obvious that the state of the country is not such as to admit of a ready or constant market for immediate consumption, which is therefore limited to the families of the fishermen themselves. Under these circum- stances, there can be no effectual or extensive fishery, nor any endeavours to take more than is required for domestic use ; unless where the small fishermen are enabled to salt and retain their several stocks, till they accumulate so as to render them sufficient for a distant market. To the natural impediments arising from want of capital, by v» hicli this is checked, must be added the difficulties inevitably 73 JiAKUA, l-JSIItliljiS. aiisii'g from the nature of the salt hiws. To favour the fisherman and promote the commerce in the salted com- modity, and at the same time to check the frauds that might follow the misapplication of the salt allowed for that purpose, have been found matters of considerable difficulty. Complaints, as may naturally be expected, abound on this subject, and, to remedy the real incon- veniences, many regulations have at different times been adopted, with more or less success. It would here be out of place to attempt a description of these several regu- lations ; as the subject is not only trite, but the changes have been so numerous, that to notice them would lead to a considerable length of discussion. To render the High- .land fisheries effective, has been an object of much anxiety, and if the expedients have sometimes failed, they have at least been intended to reconcile the more local interests of the country with the general advantages of the empire. Similar attempts have been made to temper those regu- lations which, in the case of these remote islands would, if rigidly enforced, produce inconveniences without any adequate advantages to the revenue. The restrictions on the private manufacture of candles are of this nature. Such restrictions can be attended with no inconvenience in a commercial country, but they would here be oppressive as well as useless; as there is no market for the sale of the raw, or the purchase of the wrought material, and the former would of course become unconvertible. A discretionary power is therefore judiciously intrusted to the officers in this department of the revenue, by which this manufacture is permitted for domestic use, under certain regulations capable of checking abuse without producing inconvenience. As grievances, real or imaginary, must exist every where, it will not be a subject of wonder if many other complaints are found among these remote islanders ; al- though a patient submission to inconveniences and pri- vations, Ibrms jio small feature in their character. It is pleasing how evtr to observe, t1rat they are never directed EAKIIA. FISHERIES. 73 towards the government ; an attachment to which is one of the most striking traits of the Highlander's character, to him who has been accustomed to the poHtical ill-humour of the lower orders in England. These grievances are generally however the consequence of circumstances so essentially interwoven in the system of the country, as to be irremediable ; often proceeding more or less directly from a crowded population, from poverty, and from the remoteness of the situation. In a few instances, they appear rather to be traditional than real ; the gradual influence of a number of concurring cii'cumstances, having long since removed most causes of complaint. If we consider the general poverty of the people, the distance of the seats of justice, the great competition for land, and the dependance on the landlord thence generated, together with the accumulated influence which the situa- tion of proprietor and magistrate combined, gives to the great landholders or their agents, it is gratifying to reflect that so little just cause of complaint exists. The instances of oppression which are occasionally related to strangers, will be found to belong to a period now for some time past; nor indeed are the people wiUing to submit to an improper use of power, even if their superiors were inclined to exert it. If the southern tra- veller imagines that he sees the spirit of feudal government still hovering over the dead body, he will also see that it has long lost its hold over the minds of the people. A suggestion has recently been made, which would re- move one inconvenience frequently represented to strangers in their visits to this country. It relates to the collec- tion of taxes. The produce of these being so small, no collector is appointed to receive them on the spot, and they must therefore be paid at the county town, which in the case of the island now under review, is Inverness. The inconvenience that may hence arise, in the case of errors, is obvious. It has been proposed to place the collection in the hands of the officers of excise, whose leisure, and residence on the spot, would enable them 74 BARRA. FISHEUIES. to perform this additional duty with ease to themselves and the people, and at a very slight expense. Inconveniences also arise from the difficulty of commu- nication which results from the deficiency and imperfection of roads, ferries, and post offices. With respect to the former, much has been recently done to remove them, but more is yet wanting. Tt would be too much to expect universal satisfaction where so many jarring interests are concerned, and where misrepresentation must sometimes inevitably defeat the best intentions^ of the government. There can be no doubt that its interest is concerned, in promoting for the general welfare, those improve- ments which the individuals are, in districts so poor, unable to undertake. If its intentions are occasionally obstructed by the particular views or imaginary interests of proprietors, it is no great matter of surprise. The tedious and limited communication by posts is often injurious, by preventing an early knowledge of the fluctuations of prices in the articles of export. Thus speculators in kelp, cattle, or wool, frequently profit by the ignorance of the producer. Where agriculture has a character so commercial, the free- dom of communication cannot be too great. If a small sa- crifice of immediate revenue is made for this object, either by the proprietors or the government, it will be ultimately replaced by the improvement of the country at large. A few remarks of a different nature remain to be made on the fisheries. They have been productive of advantages to the proprietors, and consequently to the country, in a way which does not appear to have been originally foreseen, however well it is now understood. These advantages con- sist in the increase of value which the lands have under- gone by their extension, even where that extension is still limited to a partial domestic supply. Hence arise the chief benefits of the crofting system, the most efficient and profitable changes of this nature having been the allot- ments of small farms on the sea shore. Rents have thus been obtained for farms of a division so minute as to have be(;n nciirly incapable of paying any froni their BARUA. ECONOMY. 15 surplus produce. In a similar manner a revenue has been derived from tenements v^^hich produce no surplus, the rent being here analogous to that which arises in the vicinities of commerce and of manufactures ; a price paid for the accommodation requisite in the fisheries, and a portion of the wages of labour. A superficial view of the limited produce and of the apparently high rent of many Highland farms of this nature, has thus been often made a ground of ill- founded censure on the proprietors ; who perhaps have not been sufficiently careful in rendering the nature of this operation intelligible to their tenantry ; if indeed it be possible to render intelligible to them what their better in- formed neighbours are so often incapable of understanding. It is no small matter in this case, as in that of taxation, to prevent a confusion of the semblance and of the reality. The grievance of a tax exists too often when the real tax is levied on an individual very different from the imaginary suf- ferer. An instance of an injudicious attempt at this dis- tinction occurs in one of the islands under review. Here, the proprietor levies a rent on each boat employed by his tenantry in fishing. The consequences are obvious ; grie- vous complaints are made of oppression and of injustice. Yet this is a case not of rigid justice merely, but of mistaken lenity, since he whose indolence or incapacity prevents him from fishing is exempted from that rent which the land alone would not allow him to pay without inconvenience or ruin. The regulation is however in every respect inconsiderate, since it not only creates an ima- ginary evil, but operates as a discouragement to the fisheries, on which the proprietor must in a great measure depend for his rent as the tenant also must for his subsistence. A stranger who for the first time sees the miserable cultivation which is carried on by the smallest class of tenantry among rocks and bogs, will be surprised to find that any rent can be paid from the produce of such pos- sessions ; in other situations they would pay none, or rather tliey would not be cultivated, since they could not repay 76 BARRA. — ECONOMY. the expense of cultivation so as to leave any profit to the occupier. Here, the great and increasing competition for land necessarily generates a rent which the habits of the farmer and the small quantity of food and accommodation he requires enable him to pay. Such rents are in many instances called oppressive. In this view it may truly be said that any rent is oppressive ; but even the abandonment of a rent, which in the case of the small tenants rarely exceeds £3 per annum, would not remove the evils under which this country labours. The fault lies deeper, and is compounded of the excess in the quantity, and the defects in the distribution of the Highland po- pulation. It is this also which constitutes the chief obstacle to the proper improvement of the land. It cannot be said that there is a want of industry or a deficiency in the labour bestowed on this object, when we examine the spade cultivation by which the small farms are generally conducted, and which was already noticed in treating of Tirey. There is, in fact, a super-abundance of labour applied to it, which under the proper direction of capital would effect useful and permanent improvements ; it is lost because it is wasted in the pursuit of those which can only be temporary. There is no want of industiy, but it is mis-directed. Here again the proprietors suffer under the unjust censure of impeding improvements by with- holding leases. But a lease to him who has no capital is nearly useless, while the only security which the land- lord can retain for the productiveness of the soil, is the power of withdrawing the farm from him who neglects it, and bestowing it on some other of the craving competitors who are surrounding him, and who come with the double claim of equal wants and greater industry. When the system shall change by the enlargement of farms and the introduction of a superior class of tenants, the pro- prietor will naturally dispose of his land with the same regard for his own interest as his Lowland neighbours ; that interest and those of his ten;mts, as well as of the BAURA. ECONOMY. 77 community at large, being seldom at variance. Before quitting this subject, it is however not uninstructive to remark, that although there can be no question re- specting the improvements of waste lands daily making by the new classes of small tenants under separate holdings and securer leases, yet the ultimate value of these improvements appears to have been over-rated by speculative persons. They are generally on too small a scale to be of future advantage when the advance in the state of farming shall cause larger tracts to be occupied. That rough land which from its nature has been necessarily cultivated by the spade, must be thrown into pasturage when more perfect and economical cultivation by the plough shall have been introduced. Under any circumstances but the present crowded popu- lation, and low value of labour*, the cultivation of such land must cease altogether ; and it will cease when labour shall become disposable under capitals less divided ; and when these, directed to more legitimate objects, shall seek for employment in the breaking up of new lands. These small holdings will therefore be eventually ab- stracted from the permanent mass of improvement, and those writers who consider the present changes as both the commencement and indication of legitimate and effectual improvements have consequently misled themselves. A small addition of improved pasture may remain, but the system is temporary, and so far from being the first stage of general improvement, is merely an amelioration of the old imperfect and imperfectible one. It is evident, * It must be remarked, that the Jow j-rice, or rather value, of'hihour nicntioned here and on other occasions as t[ie result of excessive popu- lation, is virtual only ; it is not marketable labour that is meant. On the contrary the price of hired labour in these districts is excessive, or rather, the article is not to be procured. Hence the peculiar state of the kelp manufactory, besides numerous other evils which impede the progress of agricultural hnprovcment. The causes must already have been too obvious to require detail. 78 BARRA. — SOIL, ALLUVIA. on reviewing' tlie effects of this system, that if the same quantity of labour and expense which have been bestowed on small improvements in these islands had been directed to great ones, they would here, as in Isla, have brought extensive tracts into a regular and permanent system of cultivation. But the present practice is inseparable from the present state of the population and the holdings of farms. Capital is wasted since it produces neither per- manent change, nor accession of capital, nor augmenta- tion of the means of future progress, but must always be renewed ; and it may fairly be said that the wretched Highland crops are raised at an expense much greater than their value. The introduction of capitalists and the enlargement of farms are the true foundation of the im- provement to which this country must look. A SMALL fresh water lake is to be seen at the southern end of this island, containing the ruins of a tower ; the residence of some ancient chief, or a place of refuge for his family. There are no other lakes of any note, and not a single permanent stream of water exists in the country. A few dry channels of water courses are visible on the sides of the hills, which an occasional shower fills, but which are speedily drained on its cessation. Sjjrings are almost equally deficient, a cha- racter which will be found very general throughout the remainder of the islands connected with Barra, other general features, as will hereafter be seen, per- vading the whole. *' * One uf the exceptions to this rule is somewhat remarkable. On a small rock about half a mile from the shore in Chisamil bay, stands a Castle, once a strong hold of the Macneils of Barra. It is toler- ably entire, and consists of an irregular square area, enclosed by a high wall and containing numerous buildings capable of acconi- iiuidating a considerable army, as the armies of tlie sovereigns uf those days were; perhaps 500 men. A high and strong square Keep, with no entrance but by a flight of stairs, occupies one BARRA. SOIL, ALLUVIA. 79 The deficiency of water arising from the want of springs is, in an economical view, a source of much inconvenience, not only to the inhabitants, but to the shipping which frequent the harbours. None can be obtained in summer except in the small cavities which the roughness of the ground leaves in the winter water-courses, and this, being the drainage water of the surface, is impregnated not only with peat, but often with less innocent matters. In a geological view some peculiarities seem to originate from the same cause. No banks or deposits of alluvial matter are to be observed in the fiat parts of the island or on the sea shores ; nor are there any beds of clayey soil in situations where they might be expected. There is indeed very little soil in the island, if we except the hill above Kilbar. In general the peat lies almost immediately on the bare rock in the higher parts; while on the western side many feet in depth of sand are accumulated by the incessant blowing up of that which the sea rejects. The intermediate land offers the best soil for agricultural purposes, being composed of such a mixture of peat, earth, and sand, as might be expected from its situation; the one or the other being predominant in proportion to the vicinity of the sea or of the mountain ; or the greater or less facility with which the sand drift is enabled to sweep it. The small quantity of clay which enters into these soils is some- corner of the area. The opposite angle contains a narrow tower, which appears to have been the prison. The walls are embattled on one side, and provided with a covered way and loop-holes. A small circular flanking defence covers the dungeon tower ; the remainder of the walls, as is most common, are suffered to rely for protection on the goodness of iheir masonry. Near the entrance, which is at one of the angles of the Keep, are the foundations of a circular enclosure or basin, which was probably intended as a place of security for the boats of the castle. In the centre of the area is found the spring of fresh water alluded to, which, arising in the middle of the sea, is an object of much wonder to the natives. It is secured with masonry, and arched. 1 80 BARRA. SOIL, ALLUVIA. times found forming very thin beds under the peat, which is however in general much too deep to admit of this matter being reached by the agricultural processes in use, so as to be brought into action. As there are no beds of the usual alluvia of flat lands in Barra, so there is none of the mountain alluvial matter so common in hilly countries, which consists of mixtures of angular stones with clay. The gneiss of these islands appears indeed to be of a very refractory nature, under- going little change from the action of the atmosphere. The surfaces are smoothed as if from the very slow effects of air and water, but in general the angles are tolerably sharp, and the traces of fissures penetrate to no depth. Every thing appears in its place ; the pre- cipices which result from the fall of rocks are rare, few fragments are scattered about, and those which ai'e, have an integrity and freshness rarely found in any other class of rocks in Scotland. A spectator cannot help being struck by the aspect of obstinate durability which they display. If we compare this gneiss with granite, with mica slate, with quartz rock, with lime- stone, or with trap, its superior powers in resisting destruction will be strikingly apparent ; while the ima- gination is lost in reflecting on the slowness of those changes by which many parts of the rocky globe were first made fit for the habitation of plants and animals. The difficulty with which this rock decomposes into earth, is the evident cause of the nakedness of the surface. If the lichens find a hold, it is true that they are followed by their usual attendants, the mosses, the rushes, and the grasses, which in the end produce a body of green covering wherever they can effect a lodgment. But this covering is only peat. The peat is laid on the naked rock, and the vegetation of one generation of Scirpi or Sphagnum is followed by that of others in endless succession, without change or amelioration. The cause of the extreme resistance of this gneiss is not BARRA. — GEOLOGY. 81 apparent. In composition it exactly resembles granite, and in the disposition of its parts it differs but little ; yet where most granites are covered with a dense coat of gravel, of clay, and of mixed vegetable soil, this rock is bare even to the very level of the sea. The absence of precipitous faces and of the marks of violent fracture will be found to arise from the same cause to which the want of springs is owing, namely, its freedom from fissures. There is no place in which water can lodge, nor consequently where the power of frost can be brought into action; that agent from which the violent fractures of rocks seem almost entirely to originate. Hence arises that peculiar character of the hills which predominates in a greater or less degree throughout the whole range of tlie Long Island. No serrated outline, no spiry summits, no angles nor abrupt faces vary their appearance ; one rounded and tame line separates them from the sky. A few parts only of Harris and of Lewis offer nn exception to this general rule. Nothing indeed can well be conceived less interesting in a picturesque view, than the whole of this chain of islands. Much amusing display of a sort of ichno- graphic scenery, arising from the labyrinthine disposition of the land and water, may be seen by ascending the hills, but there is scarcely any where a subject for the pencil. While the mountain outlines are tame, their groups are without complication. No trees occupy the valleys, no water-falls sparkle along the declivities, the cliffs have neither magnitude of parts nor breadth of disposition, the shores of the numerous bays are uni- formly low, and the sea rocks have neither elevation nor form to compensate for the dulness of the interior country. The rocks of Barra offer nearly as little instruction to the geologist, as they display attractions to the lover of landscape. Gneiss is the universal substance, and VOL. I. G 82 BARRA. GEOLOGY. with but little exception it will be found to predominate throughout the whole of the Long Island. This rock is here so irregular that the beds can rarely be traced for more than a few yards together in a straight line. They are commonly bent and occasionally much contorted, while their inclinations to the horizon are so irregular and inconstant, that no consistency or order can be perceived among them. Still, their leading position approaches the horizontal one ; unlike those of the southern parts of Coll, which not only are elevated at high angles, but show a considerable rectilinear ten- dency. In composition and structure they vary almost every where, the principal differences being produced by the presence or absence of hornblende, or of mica. The micaceous varieties are however rare, and the com- pounds of felspar and mica only, are seldom found to occupy any great space. They rather form the occa- sional laminee of a fundamental mass containing horn- blende in various proportions ; that substance causing the laminar appearance and fissile tendency of the rock. Occasionally this gneiss passes into common hornblende schist, while in certain situations the laminar tendency so far disappears that it assumes the characters of a common granite . Granite veins abound as usual in this gneiss, and they have in Barra a character similar to that which they possess in Coll ; the red colour however is predominant. In weathering, these rocks acquire an uniform rough surface with a slight convexity, which, together with the fissures that cross each other at considerable angles, and the occasional exposure of the veins, give to the whole an appearance resembling granite very apt to mislead an inexperienced eye, particularly from a distant point of view. Trap veins- are found traversing the gneiss, attended with some unusual appearances. In many places there are large rents filled by loose matter and vegetable BARRA. GEOLOGY. 83 soil, but appearing to have once contained such veins, of which the exposed portions have been washed out. But those which render the gneiss of Barra remarkable are of very small size, and distributed in a manner of which no corresponding examples have occurred to me in any part of Scotland but the Long Island. They are subdivided into branches of extraordinary tenuity, traversing and reticulating the gneiss or the granite veins in the most intricate manner, as either of these happens to lie in their way. However small these veins, even though reduced to the diameter of a thread, they maintain their distinctness from the including rock, never diffusing them- selves throughout its substance, or entering into any com- pound with it, but always remaining defined by a deter* mined boundary. They are readily distinguishable on a fresh fracture ; and when the rock is exposed to the weather, it is equally easy to recognise them by their rusting and falling out, while the gneiss retains its re^ fractory nature and aspect. In some places they are so abundant as to equal or exceed in quantity the rock which they traverse. Of this there is a remarkable example at Cuire. The original rock is a dark gneiss containing much hornblende and intersected by veins of grey granite. The trap veins are so numerous as to have separated the rock into small irregular fragments, so that the whole has at first view the aspect of a con- glomerate consisting of fragments of gneiss and granite imbedded in a basaltic paste. Where it has been exposed to the weather, these have been so unequally acted on that it puts on the appearance of a tufaceous lava. I must add, that the matter of all these veins, whether great or small, is invariably identical, and is a very com- pact fine-grained black basalt. No large vein of basalt is to be observed in the neighbourhood of Cuire, 84- VATERSA, &C. VATERSA, SANDERA5 PABBA5 MULDONICH,^ MINGALA9 BERNEllA.t These islands, together with a few islets of little note, form an irregular group to the south of Barra ; the latter^ which is the southmost point of the Long Isle, being popularly known by the name of Barra Head. As the composition of the whole is similar, and as they present but little interest, a very brief notice of them will suffice. Vatersa is a small island consisting of two distinct hills connected by a flat sandy bar where the opposing seas nearly meet. This small tract exhibits the broken remains of sand hills standing to mark the changes which the land has vmdergone by the gradual and alternate ac- cumulation and dispersion of these banks. There is nothing here opposed to the junction of the two seas, and the consequent division of Vatersa into two islands, but this bar, which the westerly swell perpetually throws up and which is again dispersed by the winds over the surface of the land. The separation of Vatersa from Barra is effected by Chisamil Bay, and by a narrow strait to the westward which affords passage only to small boats and is occupied like all the shores of this country by two or three small islands, of which Eorsa and Snoasimil are the most conspicuous. These islands are all composed of gneiss, differing in no way from that of Barra already described. Vatersa • The hill of Duncan. Little or nothing is known of the legendary history of the Highlands, but St. Duncan must have been a personage of importance, as Sunday is frequently called Di Donich, Duncan's (lay. Vatersa, Sandera. Water island, Sandy island. (Scand.) Ming- heal, fair. Pah, stubble. Bernera, the serrated island. (Gaelic.) t See the general Map. VATERSA,.&C. 85 offers perhaps more conspicuous examples of contor- tion and instances equally beautiful of the reticulations of the trap veins; while, as in the little island of Fudia, oxidulous iron is occasionally to be seen in the granite veins. Sandera is nearly connected with Vatersa, with which it also corresponds in materials and disposition ; forming a single hill of gneiss and attaining, like that, an elevation of 800 feet or thereabout. Although the islands of Fladda and Linga protect it in some measure both from the action of the western swell and that of the prevalent winds, it is covered by sand to a much greater height than either Barra or Vatersa; in consequence of some peculiarity of its shape which directs the current of wind high over its eastern end. This sand which, partly by its calcareous nature, and partly by its mechanical power in overcoming the tenacity of peat, has produced such ex- cellent effects in Barra and many of the neighbouring- islands, is here in such excess as to overwhelm and ex- clude vegetation altogether. At a distance the island appears as if covered with a coating of snow. Although small it is inhabited. I may add that Pabba like Sandera, consists of a single hill of similar elevation and materials ; having a somewhat precipitous face towards the west, and being inhabited by a few fishermen at its flatter eastern end. Muldonich is also a single hill of 6 or 700 feet in ele- vation, and like the neighbouring rocks it is composed of gneiss. As I had no opportunity of landing either on Mingala or Bernera, I can only conclude from the general cha- racters and disposition of the rocks, and from their con- tinuity with Pabba and Vatersa, that they also consist of gneiss. Judging from their appearance as seen from the sea and the neighbouring islands, their elevation does not appear to reach 1000 feet. Each exhibits a pre- 86 VATEilSA, &C. cipitous and rugged face, Mingala to the west and Ber- nera to the south. Some future geologist will perhaps fill up the blank which I have unwillingly left, if indeed there be any thing in those two islands but what I have conjectured to exist. He will be fortunate if he is not compelled to leave much unseen, and to supply somewhat from conjectures. Though like the philosopher in Rasselas he were to find the winds and waves obedient to his word, he would still have much to encounter. He cannot ride in a land without roads, since his horse can neither tread the bogs, nor scale the rocks. Though he may walk with the strength of Antaeus, and like the Arab live on the " cha- meleon's diet" it will avail him little, unless with the wild duck, the proper tenant of this amphibious region, he can also traverse the lakes and swim the friths. The dependance which he may place on the maritime habits of the islands will be overthrown at every step by the mis-arrangements common in this country which display so strikingly some of the characteristics of the Highlander; an almost unsurmountable indolence, and a content which is either satisfied with an expedient or submits to incon- veniences of its own creating as if they were part of the necessary career of his life. Poverty is not always the cause of these inconveniences. If the poor fisherman has no rudder to his boat, no yard to his mast, or no sheet to his sail, his richer neighbour is often equally in want of them. He who has traversed these islands will easily recognise the truth of the subjoined picture*. * It was settled in the evening that we should visit Cana Head on the following morning. Unfortunately the laird's only boat had been left on the beach without an anchor a few days before, whence it was carried away by the tide and dashed to pieces. But there was an expedient at hand, as there was another boat in the island, and it was borrowed for the occasion. In the morning, when ready to embark, it was discovered that the borrowed oars had been ncgli- ERISKA, &C. 87 ERISKA, FUDIA5 HELLESA, GIA.* Numerous islands lie in the strait between Barra and South Uist, and on the eastern shore of the former, one small chain of which separates the harbour Ba hiravah from Ottervore road. The composition of the whole is precisely the same. Eriska is the boundary of Ottervore toward the north, and is separated from South Uist by a narrow and rocky sound, being of considerable extent when compared with the neighbouring islands. On a detached and high rock at its southern end are to be seen the remains of a square tower, the ancient residence of some tur- bulent chieftain. This island offers also a circumstance of historical interest, having been the first place on which Prince Charles landed while on his voyage from France to Arasaik, where his disembarkation took place. gently left on the beach on the preceding evening, and had like the former boat been carried away by the tide. There was now a boat, but there were no oars. Oars could be borrowed, somewhere : they would be ready at some time in the day ; at twelve or one o'clock j it would not be many hours too late ; we could only be benighted in returning. By the time the oars had been sent for, it was dis- covered that the boatmen and servants were all absent cutting peat in a neighbouring island. But it was possible to find another ex- pedient for this, by procuring some of the islanders. A messenger was accordingly sent for four men. In the meantime the borrowed oars of one fisherman were fitted to the borrowed boat of another, but alas ! all the islanders were absent making kelp. Thus the day was spent in arranging expedients and in removing obstacles. Thus is life spent in the Highlands, and thus will it be spent by him who trusts to Highland arrangements for the accomplishment of his objects. * See the general Map. S8 ERISKA, &C. Although the gneiss of Ehska presents no features deserving of particular notice, that of Fudia is somewhat distinguished by the magnitude and number of the granite veins which it displays. Lumps of granite, apparently independent of veins, are also seen imbedded in it. From these as well as from the larger veins there proceed branches anastomosing and diverging in a very capricious manner, which the great continuity and extent of the naked surface gives ample opportunities of examining. The felspar of these veins is remarkable for its purple hue, and it is found in large concretions, as is usual iu the granite veins which traverse gneiss. Large masses of confusedly crystallized hornblende are also found dis- persed throughout the gneiss. A few veins of quartz are seen traversing . the rock. These are of small dimension, not exceeding two or three inches in breadth, yet they present circumstances of some importance in the history of gneiss. It has been generally supposed that the quartz veins of this rock as well as those of mica slate, were of contemporaneous origin with the substances in which they lie, or, at least, that they have been formed by a secretion of quartz into cavities produced by the shrinking of the adjacent parts during the process of induration. But these veins are here attended by a distinct shifting of the rock which they traverse ; a circumstance sufficient -to prove their posteriority, and the forcible dislocation of the parts which bound them, at a period more recent than that at which the rocks acquired their form and disposition. In the instance under review the changes in the gneiss belong to two distinct periods, since it is first displaced by the intrusion of the granite vein, while the gneiss and the vein together are subsequently shifted by the quartz. The subjoined drawing* will serve to give an idea of the ♦ PI. II. Hg. 3. ERISKA, &C. 89 appearances in question, as well as of" a still more recent change induced by the intrusion of a trap vein. The last circumstance in Fudia worthy of notice, is the existence of oxidulous iron in the granite veins. This is accompanied by black mica, and forms detached masses of the size of an apple, or thereabout, protruding from the surface of the rock. Although Hellesa and Gia correspond in every respect with Barra in structure and character, they exhibit one of the most striking features of that island in a still more accessible form. This is the passage of the trap veins through the gneiss. It is difficult, perhaps impossible, in Barra to trace the reticulations of the basalt to a principal mass : a geologist therefore, limiting himself to that island, might easily pass over the whole without remarking this phenomenon, or he might neglect it as one of the ordinary forms of contorted gneiss, or, if he observed it, remain unable to explain it for want of a clue. It is one of those recondite appearances in the disposition of rocks which points out the necessity of rigid and minute research combined with the more general view of broad and leading characters. On the shores of these small islands the larger trap veins are seen in various places, and they are easy of access. They are in general distinctly pointed out by the vacuities which the action of the sea has caused. The water gradually insinuates itself, not only between the walls of the veins and the body of rock, but among the trans- verse rifts of the veins themselves, detachins: them in masses which the waves wash away, leaving open rents and semi-cavernous appearances. These veins vary from three to six feet in thickness, and are generally in an upright position, but affect no particular direction. It is not difficult to pursue their ramifications, which pene- trate the adjacent rock, often to a considerable dis- tance, producing the appearances already described in speaking of Barra. It will hereafter be seen that 90 ERISKA, &C. this phenomenon occurs in many other islands in this chain. I may here add that as Wia, Fladda, and the smaller neighbouring islands, perfectly resemble these, as well as Barra, in structure, it is superfluous to make further mention of them. SOUTH UIST. GENERAL DESCRIPTION. 91 SOUTH UIST.* This island, the most extensive of the group which constitutes the southern half of the exterior chain, is sepa- rated from Barra by the islands of Fudia, Eriska, and some smaller ones, and by a sound interspersed with sunk rocks. Excepting the sound of Harris this is the only one throughout the whole chain which affords passage to ships, but it is dreaded by mariners even more than that strait, on account of the distance to which the danger- ous ground extends westward. From Benbecula at its northern extremity it is also separated by a shallow strait interspersed with rocks and flat islands, intricate beyond description. The retiring tide leaves a bar of sand which is so nearly uncovered at low water, as to admit of a communication between the two islands. On the eastern side the coast is rocky throughout, although scarcely ever precipitous, and the water is deep, with a clean shore. On the western it presents one uniform flat shore of sand free from outlying rocks. The total length of South Uist is twenty miles and its greatest breadth about nine. It may readily be divided into two nearly equal portions, by an imaginary but irre- gular line extending north and south. The western half affords no subjects for the mineralogist, presenting one unifonn alluvial flat of peat, interspersed with numerous lakes and skirted toward the shore with sand. The eastern division is mountainous and rocky, and is intersected by sea lochs which enter far inland, winding about in the most sinuous directions, and covered with rocky islands. The mountains which form the eastern side of South Uist cannot * Uist; corrupted from Vest (Danish) the west island. For this and the remainder of the Long Island it is necessary that the reader should consult the general Map, as the nearly uniform geological structure of the whole chain renders detailed ones unnecessary. 92 SOUTH UlST. GENERAL DESCIIIPTION. be said to constitute a chain ; they rather form three dis- tinct groups. That which hes between Loch Boisdale and Kilbride consists of three or four somewhat distinct and rounded eminences scarcely rising to the altitude of a thou- sand feet. They do not here extend far westward, since this lake in its ulterior ramifications reaches into the flat country. From Loch Boisdale to Loch Eynort the hills rise to an altitude more considerable and extend further westward ; enclosing the head of this lake, which never- theless is protracted like the former into numerous intri- cate and involved channels, separated by rocky eminences and occupying beautifully sequestered valleys, now barren and deserted, but susceptible under a more favourable climate of eveiy variety of picturesque ornament. To the north of Loch Eynort the hills still rise in elevation, forming a conspicuous ridge that is seen far at sea and occupies a considerable portion of the island. This ridge gradually declines by a long slope into Loch Skiport. Its highest elevation is Hecla, resembling however in no other respect but appellation, its very celebrated namesake. A storm of wind and rain prevented me from observing its barometric altitude, but it is probably not much short of 3000 feet. The faces of these hills are all covered with rocky protuberances, rounded and independently scattered, as the gneiss rocks in this country most com- monly are. The summit of Hecla alone presents some abrupt and broken faces, but they are of small dimensions. At Loch Skiport the hills disappear, and are succeeded by a group of low rocky islands and promontories which checquer and diversify the intricate mixture of land and water by which South Uist is separated from Benbecula. Loch Skiport penetrates so far to the west, but veith a change of name to Loch Gamoslechan, that it reaches the western sea, and thus separates a portion of South Uist in the form of a low flat island, which is not however distinguished by a separate appellation. SOUTH UIST. — SOIL, SURFACE. 9^ Except the great tract of peat which I have described, and the minor patches of sand found on the western shore, there appears to be no alluvium in South Uist. The only detached stones to be found, are fragments of the gneiss of which the country consists, and these are rarely marked by the signs of attrition which indicate either a distant period of separation or a long-continued state of motion. The western side of the island is, however, subject to considerable alterations in its figure and dimensions from the shifting of the sands of which it is principally formed. This is a phenomenon common to almost the whole western side of the Long Isle, from Barra Head to Loch Tarbet in Harris. I have already mentioned its occur- rence in Barra and the southern isles, but as 1 shall have occasion to examine it hereafter when describing North Uist, I forbear to dwell on it here. The lakes that occupy the flat soil on the western side of the island, neither receive nor give exit to any streams. They are generally shallow, often not exceeding two or three feet in depth, and appear to be the mere repositories of that drainage from the surface to which a country like this must be subject. Their waters are invariably brown, from a considerable solution of peat. The whole island is indeed destitute of streams, since the ephemeral torrents, of which a few can be traced flowing down some of the declivities during a heavy fall of rain, scarcely deserve that name. They vanish as they arose, since they are not supplied by springs, not one of which has I believe been observed. This want of springs must be attributed, as in Barra, to the nature of the rock, which presents neither receptacles for water nor fissures for its transmis- sion. At the same time it must be remarked that the climate is far from rainy, the clouds, which generally pass the sea with rapidity, meeting no material obstacle until they arrive at the continental land of Scotland. Hecla indeed, and the mountains about Loch Eynort, are, in con- 94 SOUTH UIST. AGRICULTURE. sequence off their height, subject to many showers from which the remainder of the island is exempt. With a general resemblance to Barra in the nature and disposition of its surface, considered as a subject of agri- culture. South Uist presents some differences. The belt of sand on the west is more continuous and better defined, while the middle region is a tract of moory flat ground separating the sandy soil from the mountainous district. The sandy region presents a most desolate appearance when the crops are removed and it has assumed its winter dress ; but, like Coll, it is enlivened in spring with a pro- fusion of clover and other wild flowers, which give it an aspect of cheerfulness and a brilliancy of colour to be found no where but on the sandy tracts of these islands. Barley, oats, rye, and potatoes, are cultivated throughout tlie whole, by the assistance of sea-weed and the ordinary manures.* Portions of the middle tract are also in cul- tivation where the ground is firm and naturally drained by means of the lakes which are scattered in profusion throughout it : the remainder is a gloomy extent of black peat, but like the middle soils of these islands in general, is undergoing a gradual amelioration from the diffusion of the blowing sand along its surface. Beyond this tract towards the east, the ground rises into low subsidiary hills skirting the higher mountains. These are deeply covered with peat, which is however, like the middle district, naturally drained by means of cuts produced from the flow- ing of the surface waters ; and they are thus rendered capable of cultivation, holding x)ut at present the chief temptation to general and lasting improvements. * There is a sort of cultivation occasionally seen on the sea-shores of the Highlands at which a stranger will be much surprised. Sea-weed is strewed on the shingle above the high-water mark, and on it is sown barley (bear). As it disappears during the growth of the corn, the crop is in harvest time seen covering a surface of pure rounded pebbles of quartz or granite without a vestige of soil. SOUTH UIST. GEOLOGY. 95 The mountainous district is not highly productive of pasture, and is principally, perhaps not most profitably, applied to the rearing of black cattle. This appropriation of the mountain pastures of the Long Island is however to a certain extent unavoidable, as the difficulty of trans- porting sheep to the main land is, from the length of the voyage, so considerable as materially to discourage that branch of pasturage. The want of roads is a serious obstacle to the improve- ment of this island, which is peculiarly difficult to traverse in any direction. The introduction of these would form the first step to improvement. A few feeble attempts to plant trees have been made, but they have beea attended with little success : the whole appears a naked and dreary waste. The reader is doubtless prepared to find that the rocks of this island consist of gneiss : such is the fact, while they afford scarcely any varieties to interest him after what has already been remarked of the southern islands. Still, there is a change of character, the gneiss being here almost uniformly of a granitic aspect, or this variety being at least predominant. The external forms are indeed so like those of granite, as, at first sight, almost to mislead an observer. In the internal stmcture it also approaches very near to that rock, although there is always to be observed somewhere an indication of the fohated tendency. I must here remark, for the sake of those who may be little conversant with rocks in their natural positions, that specimens may frequently be ob- tained from beds of gneiss, undistinguishable from genuine granite. It is true that they may sometimes be portions of granite veins, but in other cases they constitute real integrant parts of the gneiss beds. However proper therefore it may be to consider them as granite when viewed as cabinet specimens, it is still necessary that they should be arranged as parts of a gneiss series. The views 4 96 SOUTH UIST. — GEOLOGY. of the geologist embracing a wide field must not be limited by variations which are minute, irregular, and inconstant, and which do not affect the broader principles that regulate his investigations. This remark is applicable to many other cases where occasional variations of small extent and importance take place, and where specimens of a distinct rock will intrude into a class otherwise geologically very consistent and strongly defined. Such accidents may perhaps be considered in the same light as the formation of independent minerals in similar situa- tions, and they require attention, lest from an occasional specimen of such anomalous or accidental rocks, the cha- racter of a whole district should be mistaken. From Kilbride to Loch Boisdale the position of the gneiss is extremely irregular. It occasionally contains irregular lumps of garnet of an intense brownish black colour, with a vitreous lustre and smooth conchoidal fracture. Although so much resembling granite about Kilbride, it resumes the more comnion foliated character as it approaches the shores of Loch Boisdale ; abound- ing in hornblende, and containing distinct portions of hornblende schist and of common hornblende rock. Few granite veins seem to exist throughout this tract ; where they occur, they sometimes possess the graphic character.* ^ From Loch Boisdale to Loch Eynort the hills descend gradually into the sea, but on the right hand of the entrance an abrupt face of cliff is seen of about 100 feet in elevation, tenanted by cormorants and rock pigeons. The external features of these cliffs indicate a difference in their structure and in the nature of the rocks. They * Tlie remains of a castle are visible at the entrance of Loch Boisdale, hut so far ruined that little more tiian the foundation exists. Tiiis country indeed is as uninteresting to the antiquary as to the lover of natural beauties; oflering little or nothing for the gratification of either. That which is rndr {<•, not grand, and that whicli is intricate is but rarely pirturesque. SOUTH UlST. GEOLOGY. Wt exhibit on close examination the same appearances whicli in a more limited manner occur in Barra, Gia, and Hellesa. Here the magnitude of the trap veins and the extent of surface exposed render the junction more extensive and the disturbance much more striking. I have already detailed the nature of these junctions so minutely that it is unnecessary to repeat it. But in this place may be seen very perfectly the conglomerated nature of portions of the trap vein. This is a matter of considerable difficulty to explain, since, as far as I yet know, the trap conglomerates have been invariably found forming portions of masses, or else entire beds. The conglomerated substance consists in some places of frag- ments of trap imbedded in a trap basis, while in others the imbedded masses are of gneiss and granite. As the cliffs are of very difficult access, I do not speak veiy decidedly respecting the latter variety, as it may be a fallacy arising from the intermixture of fragments of the original rock with minute reticulating veins. The basalt of this vein acquires by the action of the sea on its surface a dark green colour. Where it has been subjected to atmospheric action only, it is cavernous and scoriform, resembling very much some varieties of iron slag; and it is invested with a black sooty powder in those cavities which are protected from the rain. The bottoms of these cliffs are coated with spongia papillaris, and various other marine productions. All the hills which skirt Loch Eynort are of gneiss, and among them the varieties which contain hornblende predominate. Its disposition is equally irregular as at Loch Boisdale, and veins of granite are equally rare. Among them are seen concretions of a very dark grey felspar, and similarly large ones of common hornblende. Quartz is of rare occurrence. Nothing indeed can be imagined more tiresome to a geologist than the perpetual and almost unvarying recurrence of gneiss, which forms the lowest as it rises to the highest parts of this cheer- VOL. I. H 98 SOUTH UIST. GEOLOGY. less country. The same rock continues to occupy tlie remainder of the group from' Loch Eynort to Loch Skiport, including Hecla ; the only substances capable of attracting attention appearing to exist in the granite veins, which present uncommon and beautiful mixtures of grey and black quartz with white felspar. Of the innumerable islands which are found in Loch Skiport and in Kyleslewsa, interposed between South Uist and Benbecula, I examined only a few. They all appear to be portions of the same rock which constitutes the rest of the country, among the protuberances of which the water insinuating itself, has generated a multitudinous archipelago, which no patience could investigate, unless under greater temptations than those presented by gneiss. The similarity in the structure of Benbecula, next to be described, adds a sufficient confirmation of the truth of this conjecture. BENBECULA. — GENERAL DESCRIPTION. 99 BENBECULA. This island is seven miles in length and eight in breadth, being of an oval shape. Although divided by a channel from the north end of South Uist, it is, in a general view, undistinguishable, the division produced by that channel being so intricate and narrow as to be often invisible. The island of Wia placed at its south-eastern extremity, and that of Grimsa, which lies in the strait that separates it from North Uist, may also in a physical view be conceived to appertain to it, as they present the same aspect and are constituted of the same rocks ; while that of Rona, equally near with Grimsa, will be found both in character and composition to form a part of North Uist. Sundry small islets and rocks are scattered about its eastern side, and in each of the north and south channels which separate it from the neighbour- ing islands. These partake in their nature of the approximate shores, with one exception which I shall point out in its proper place. The eastern side of the island, and the eastern portions of the northern and southern boundaries, are characterized by those tortuous and intricate indentations of the shores which occur in South Uist. But they far exceed these in their capricious sinuosities ; forming a labyrinth from which a stranger, attempting to move among them whether by land or water, is unable to extricate himself. Of these indentations. Loch Uskevagh is the most remark- able, occupying a space of ten or twelve miles in circum- ference, in which the land and water are dispersed among each other in such equal proportions and such minute divisions, that it is difficult to say which predominates. The visitor who attempts to explore it is unexpectedly surprised by the occurrence of new channels and fresh headlands when he had imagined himself at the end of his voyage ; and in the multiplicity of islands and pro- 100 BENBECULA. GENERAL DESCRIPTION. montories which open and shut upon him on all hands, loses the recollection of his place, and the clue to his return. Surprising and pleasing as this scenery is, it offers nothing picturesque, from the almost absolute identity of the parts and the lowness of the land ; which consequently possesses no features adapted to land- scape, void as it is of trees and of discriminating objects. Nature may be truly said to have here wasted her capa- bilities on a climate to which she has refused vegetation, nay almost denied a soil. The imagination may paint these watery regions situated in a fine climate with sunny skies, adorned with trees, decked with flowers, and em- bellished with works of art ; and may, with Mirza, in its dreams transport itself to the flowery islands of the blessed. But the spectator soon rouses himself from his trance, and sees grey rocks covered with brown heath, and shores deformed with sea-weeds, among which a rising and falling tide alternately conceals and exposes a bottom of dark ooze. The western side of Benbecula is bounded by a flat sandy shore, and, except one large indentation, presents a sea line comparatively even. Lower in level it cannot well be, since the land scarcely rises any where twelve feet above the high water mark ; but it is freer from rocks than the eastern, and presents therefore a more uniform flat. The sand which forms part of this western shore extends to the north and south channels, producing bars called the north and south strands, which the retiring tide leaves nearly dry, so as to present fords of commu- nication between the islands. The interior land, which in a general view is of a flat aspect, is interspersed with low rocks and irregular eminences not exceeding a few feet in height. Its eastern half is almost entirely covered with peat, on which scarcely any vegetables grow but Erica tetralix, starved plants of Erica vulgaris, and a few of the moory grasses ; the greater part exposing the naked brown surface and being intersected with numerous soft bogs. In summer it is difficult to cross it, in winter BENBECULA. GENERAL DESCRIPTION. 101 it must be impassable. The western division exhibits a better soil, being more sandy and affording in conse- quence a verdant surface, dry and convertible to agricul- ture. The whole of this surface is chequered by a pro- fusion of fresh water lakes, which wind among the rocks, and together with the indentations of the sea, give to the whole island a most singular aspect. I attempted in vain to number them from Benbecula hill, but after reaching to ninety was obliged to abandon the dazzling pursuit. This hill is the only one which the island possesses. It is a roundish extended mass, and appears to be between 600 and 700 feet in height. From its summit a very extraordinary view presents itself, the whole of the island beneath detailed as in a map, and the southern and northern islands extending to an un- defined length with all their mottled plains and scattered mountains ; while the more eastern lands of Sky and Rum, with the adjacent continent, are distinctly visible in the horizon. After the remarks already made on the subject of water in describing the preceding islands, it is unnecessary to say that Benbecula possesses no running stream, of which indeed its flat surface is a sufficient indication. The lakes with which it abounds appear to be merely recep- tacles of rain water, varying in depth from six inches to as many feet, and all highly tinctured with peat. All the lakes of these islands abound with trout, and produce many of the alpine aquatics. In this I remarked abun- dance of the Ranunculus lingua, and R. gramineus, plants not very common in Scotland. The sea lochs and indentations abound also in those sea-weeds, from the produce of which converted into kelp a principal part of the value of this, as of the other islands, arises. This manufacture affords occupation for numbers, and the labour employed in it is the common substitute for rent, as I shall have occasion to notice hereafter. There are no changes of the surface in action on the eastern side of Benbecula, if we except the gradual and 102 BENBECULA. HIGHLAND POPULATION, constant accumulation of peat. But on the western side the blowing of the sand produces an annual exten- sion of the shore. The inhabitants even talk of a period within their memory, at which Castle Wia, now a mile from the sea, was surrounded by water. This pheno- menon, already noticed in these islands, is the reverse of those changes to which land is in ordinary cases subjected. Accumulations of soil and extensions of the sea shore at the mouths of rivers are not uncommon, and the addition is in these cases made by the waste and transportation of the higher land, of which a portion is also carried to sea and deposited at its bottom, gra- dually diminishing its depth, and probably laying the foundations of future stratified rocks. In this case on the contrary, the opposite effect takes place ; the deposits generated at the bottom of the sea by the constant destruction of shells, being driven towards the shore by the action of the waves and ultimately dispersed by winds over the land ; where, with the assistance of plants, they at length become a permanent addition to the soil, extending the coast and causing the sea line to retire. Benbecula, like Barra and other parts of this outer chain, affords one of the most striking examples of that redundancy of population for which the Highlands have in many places been so frequently remarked. It is a question too interesting to be passed over in absolute silence, although a very slight notice alone of this and similar subjects is compatible with the design of this work. It has hitherto been discussed with much warmth, in consequence of its connexion with many interests ; the judgment of an uninterested person, although perhaps less competent to treat it, will at any rate be unbiassed. But we must not stumble at the threshold of the argu- ment. A population is redundant, whatever be its absolute numbers, where the labourers, whether, as here, in the shape of kelp makers, of farmers, or of fishermen, are without sufficient employment, and where without an increase of BENBKCULA. HIGHLAND POPULATION. 103 it they are unable to command a fair proportion of the necessaries of life. No one who is acquainted with this countiy can doubt the fact itself, as far as relates to the means of living, which are not the less deficient because the deficiency is universal. Riches and poverty to a certain extent may be relative, but there is a point at which poverty is absolute, and where it does not cease to be an evil although divested of those additional griev- ances which are the result of a comparison with superior wealth.* When therefore it is asserted that the population is not now redundant, because it v/as equally supposed to be redundant thirty years ago, and has yet materially increased within that period, nothing is proved but that the means of living, which are the result of an additional quantity of productive labour and of a cause still more obvious, the introduction of the potatoe, have themselves increased. Although a nice equipoise of the two, similar to that which existed at the commencement of the pro- cess, may not have been preserved at all times, yet under certain slight fluctuations, the population and the produce have held a common pace together. No parallel can in a case of this nature be nicely consistent throughout, and accordingly the demand has in many instances out- stripped the supply, and the excess of population has been felt at various times in the want of farms to culti- vate, of labour to perform, and consequently, of the means of living. At others doubtless, the supply has exceeded the demand, as must sometimes necessarily happen, and thus the contradictory statements of dif- ferent observers, too much generalized but equally founded on facts, are to be reconciled. If the only statements we * Though the poverty of the people is here so great, we must beware of attaching to the term the debasing ideas with which it is associated in Eni'land. It is not at variance with the numerous moral and physical virtues that strongly characterize the Highlanders. The reader will probably recollect a parallel distinction which Montesquieu has drawn on this subject. 104 BENBECULA.- — HIGHLAND POPULATION. can command are to be relied on, the actual population of the Isles appear to have been nearly doubled in the last sixty years. It is indifferent for the present purpose whether this statement be very precise or not. The existence of frequent scarcity or of absolute famine during the early parts of this period, but chiefly before it, are a sufficient proof of redundant population in those times. There have been no instances of famine recently, for even the great increase of population has been exceeded in rapidity by that of the means of living.* The redundancy is unquestionably much less than formerly, but it still exists, and must necessarily under the present circum- stances of these islands proceed in a constant increase till it reaches the same limit which it touched sixty years ago. Where that limit may be placed we cannot tell, but it is evident that wherever so near a race is run on this ground, an interference must occasionally occur, or those inconveniences arising from occasional excess of population must take place, of which Benbecula among other districts presents an example. A consideration of the nature of this argument as far as relates to the past is sufficient for illustrating it as to the future. It is contended that no removal of the people is necessary, because the means of living are increasing in proportion to their additional numbers. * Although this is true in a general sense, it must not be too strictly taken, as the inhabitants, both of the islands and the western coast, whose means are at present but barely calculated to meet their consump- tion, occasionally suft'er great privations on any check to their harvest or to the expected produce of their fishery. The last year (1817) was peculiarly marked by an interval between the consumption of the old crop and the ripening of the new one, attended with distress approaching to famine. In Sutherland numerous families subsisted on fish alone, often on shell fish, for near two months, neither meal nor potatoes remaining. At length, although the coast abounded with fish, the men were so enfeebled that they were unable to row their boats out to the fishery, and many were confined to their beds from the consequences of exhaustion. BENBECULA. HIGHLAND POPULATION. 105 But the point of distress having once arrived, it is im- possible to wait for the tedious operations by which it is to be remedied, as it ultimately may, since the demand for relief is imperious, and to withhold it when it can be given is cruelty. The redundancy must be removed if possible, by diverting it to those places where there may be a demand for labour ; and to argue against the pro- priety of this measure, admitting it to be practicable, is a proceeding as distant from good poHcy as from humanity. The criterion by which the excess of population in Ben- becula may be judged of, without having recourse to the insufficient helps of numerical investigation, consists as much in the minute division of farms, as in the low price of labour. The state of the kelp manufacture is a sufficient proof of this latter fact, it being conducted at a much lower price than in the neighbouring districts. The comparative poverty of the inhabitants corresponds, and, as is usual in similar cases, ill-founded complaints prevail, of oppression on the part of the proprietor in the exaction of so large a portion of labour for the occu- pation of tenements so small. We cannot expect juster views of political economy among these wretched inhabit- ants than we find among their betters ; and it is in vain to remind them that even the unconditional surrender of the whole land would in a short time leave them as poor as they now are. Under this pressure their attach- ment to the soil is insuperable ; no consideration appear- ing to have any power to induce the wish for a change of place, though even far short of actual emigration. It is sufficiently difficult to effect such a change of place even in more common circumstances, since " Man" it has been well observed, " is of all lumber the most dif- ficult to move, " but the degree of attachment here, and generally throughout the country, is such, that scarcely any considerations are able to overcome it. There is in this case however as in many others, an apparent con- tradiction, since there has been a time when the inhabitants 106 BENBECULA. HIGHLAND POPULATION. of tlie Long Isle were noted for their propensity to emi- gration, and when considerable numbers removed to Ame- rica. But these emigrations seem to have been the result of a contagious or sympathetic feeling in particular tracts. It has always been difficult to remove individuals or single families, yet occasionally whole tracts have emigrated together, to the no small terror of many patriotic indi- viduals, whose political knowledge was less commendable than the goodness of their intentions. This taste is however at present dormant ; but I shall have occasion to consider the subject again. It is maintained by many persons that emigration is never necessary : it is even said that no migration from any individual island or estate is ever requisite, and that employment may be found in the cultivation of fresh lands and in manufactures. I must postpone the question of manufactures, although they form an expedient the futility of which is easily shown. Benbecula might perhaps dispose of a portion of its present excess of population on its own lands, as well as might South Uist; but it must be under a mode of management very different from the present. Let us however examine the same question as it relates to Barra and to North Uist. The arable land of Barra bears a small proportion to its pastures, and it may, I believe, be safely stated, that eveiy thing arable or capable of permanent improvement is already in a state of cultivation. In any other circum- stances indeed, the cultivation of Barra would be judged excessive and injudicious. A change of system, such as in many instances might be productive of advantage, would therefore in Barra only tend to diminish the number of occupants, by diminishing both the quantity of produce capable of being immediately consumed on the soil, and the labour required for the cultivation of that land which ought to be maintained in agriculture. In the present state of the island moreover, a large proportion of the population is supported by the produce of a very active JiENBECULA. HIGHLAND POPULATION. 107 fishery, as I have already shown. Could this fishery be indefinitely increased there would of course be no limit to the increase of population. But this cannnot be done precisely as it is required to meet the additional demand for employment and food ; perhaps it cannot be done at all. In the mean time the people of Barra have exceeded the demand for this and eveiy other em- ployment, and have entirely occupied all the land capable of cultivation. They are therefore redundant, and as a sufficient practical proof of such redundancy, it is only necessaiy to state that there is a considerable village at Kilbar for which no land is to be found; land, which in a country without markets, forms so indispensable a requisite in the economy of a Highland family. A single acre has by the humanity of the proprietor been given to this community for the cultivation of their potatoes, and a wretched existence is thus w^orn out by them, partly by this resource, partly by the fishery in which the men are engaged ; both of which being insufficient, the women and children are constantly employed in digging cockles on the sandy shores, offering a spectacle of poverty which is painful even in this country where it is daily seen in all its modifications. The case of North Uist, which I shall introduce here for the purpose of bringing the whole evidence under one collective point of view, is of a different nature, but equally instinctive. I need not describe at large the beneficial change which has taken place in many parts of the Highlands by the alteration in the mode of letting farms, since it is now generally known. It is sufficient to say that but few instances remain of the ancient mode of tenure in common, or by run-rig ; the separation of each common farm into separate crofts or holdings having been adopted by most proprietors, and with evident advantages to all parties. In consequence of this system in some measure, but partly also from the assignment of new lands to 108 BENBECULA. — HIGHLAND POPULATION. many of these crofters, accommodation has been found on the main land in many instances for a much greater number of people than before ; while a great deal of fresh land has been brought in, from the new stimulus given to the industry of the people by the possession of an independent kind of property, instead of a lax interest in a joint and often-changing lot. In conse- quence of this arrangement, it has happened that large tracts have been thrown into sheep farms, with little difficulty or distress from the removal of the ancient tenants, while the produce of the estate and the pro- prietor's revenue have been materially increased. But cases have also occurred, where the crowd which oc- cupied the common farms of an estate, have been too numerous to admit of a separate lot of sufficient extent being assigned to each, and here the excess of popu- lation has been brought to light by the very same practices which have in other instances caused it to be absorbed in the acquisition of new employment. This event has taken place in North Uist, and to those who are acquainted with the humanity and intelligence with which that estate has been conducted and divided, it will be unnecessary to say that no precaution has been omitted to prevent the evils which have followed. Yet, an hundred families, containing about five times that number of individuals, have been dispossessed, and are now without land, and from the nature of things under the Highland system, with very insufficient employment. A great proportion of that number may fairly be con- sidered as redundant, and there is no doubt that their own interests as well as that of the proprietor requires their removal. Hereafter it is possible, that the changes to be expected in the improvement of the land from the adoption of the new system, may be able to absorb this population or even more ; at present a remedy is wanted for the excess. It may be asked, how the same people were accommodated with land before the division, BENBECULA. HIGHLAND POPULATION. 109 and the question is easily answered. Under the ancient common holdings where no man's lot was defined, no just idea was entertained of the limits of the land or of its value. Thus, a farm let to ten or twenty tenants readily accommodated two or three more, the sur- render requisite for these superfluous hands being such that no one felt his particular share of the sacrifice. In this way every farm was encumbered with, two or three idle and gratuitous retainers, who, from the claims of kindred or other causes, were allowed to drag on in this way a miserable existence. At present the lot of an individual admits of no such lax charity, and those who have been ejected are thus driven to a mingled state of insufficient labour and beggary. The state of things here described is not limited to the outer islands only. Rum, among others, furnishes an example of a similar evil, where the chief part of the burden has however been hitherto borne by the proprietor. But it is not necessary to go into details of facts sufficiently known to all those who are acquainted with these islands, however they may have been doubted or denied by others whose opinions were formed on a partial knowledge of the country. As far as the pro- prietors are concerned, it is an act of palpable injustice to expect from them the total sacrifice of their properties, independently of the evil which the community in general must suffer from the imperfect state of management to which their lands must under such circumstances be necessarily condemned ; particularly as the remedy is far from adequate, and can at the best but remove the day of change and reckoning to a somewhat greater distance. The change will in fact be the more severe the longer it is protracted, since greater numbers will be added to greater poverty. The Englishman, to whom the habits and feehngs of this people are unknown, will be surprised that such a state of things can exist at all, and not less so to find 110 BENBECULA. HIGHLAND POPULATION. that it is difficult to apply a remedy. He expects that the natural overflowing of people in one place, will without effort discharge its superfluity on those where there is a deficiency. He is unacquainted with the per- tinacity with which the Highlanders adhere to their place of birth, and that, it would seem, exactly in the inverse ratio of all apparent causes of attraction. At the same time it must be remarked, that the insulated state, the peculiar habits, and the language of these people present additional obstacles to migration ; and that many changes, yet far distant, must be made before such a free commu- nication can be established as shall allow it to take place without eflbrt and without pain ; before it shall become a current part of the system of action. Any expedients which shall break through these habits and destroy these bounds, will facilitate this measure so much to be wished, and by abolishing distinctions in the community at large, render the interchange of all its constituent parts easy. A common standard of pursuits, occupation, language, manners, and wants once esta- blished, would remove these obstacles ; but an exa- mination of the several means by which this may ul- timately be effected would lead into a chain of discussion far beyond the bounds to which I am limited in this very general sketch of the economy of these islands. It is sufficient to have thrown out these hints on the eventual remedies. It will be seen that much may perhaps be done by methods which, although apparently not leading directly to the wished for alterations, will facilitate and hasten them. Tlie views thus held out, of the facility with which an occasional migration, adequate to meet the varying demands for population in different districts will take place when the total system of the country shall have been changed, are abundantly exemplified in Isla. Here the change is nearly completed, labour has found its level, and no difficulties are experienced either in commanding an additional population when wanted, or in 2 BENBECULA. HIGHLAND POPULATION. Ill rejecting it whenever fresh arrangements in the divisions of land and the improvements of farming, render it an incumbrance. Thus far I have only looked to the general circum- stance of migration, and after the numerous and often intemperate debates which have existed on the subject of emigration, I would willingly pass it without notice lest I should entangle myself among the host of con- tending adversaries. The unfortunate connexion which subsists between certain terms and the concatenated trains of prejudices or feelings which they excite, is such, that it is difficult to render the simplest truth acceptable where these are called into use. If we could banish the words emigration, depopulation, en- grossing of farms, and some others equally offensive, from these discussions, they would be attended with com- paratively little difficulty : to divest these terms of their odious attributes is impossible. Yet it is plain to every one in the least familiar with the principles of political economy, that the evils arising from emigration are almost in every instance imaginary, and that to oppose it where there is such a tendency, while it is an evil to the community at large, is no less a grievance to the indivi- duals who would resort to that remedy, than a forcible deportation would be to those who were ir^plined to stay. It is not too much to add, that the individual, or the government, which protects the liberty of the subject in all the arrangements best adapted both for his own and for the general welfare, is only extending the exercise of its protection when it facilitates such measures by re- moving the artificial or natural impediments that stand in its way. The subject of depopulation is too trite, and the popular terror respecting its evil consequences too groundless, to deserve notice. But I must pass from a subject too interesting for the space which I can afford for it. In the mean time no great difficulty seems to exist in reconciling the apparently discordant opinions of those who have adopted different sides in 112 BENBECULA. HIGHT.AND POPULATION. this much agitated question. The evils that resulted from the change in the state of the Highlands which followed the events of 1745 and the subsequent intro- duction of sheep farming into many districts, undoubtedly found a relief by emigration, and then justified its utility. But on the one side it appears to have been looked to as the only remedy, while on the other it was maintained to be always unnecessary, and at the same time deemed politically inexpedient. The objection of poHtical inex- pediency must be given up by its supporters ; yet it must at the same time be admitted, as abundant expe- rience has since shown, that the process of crofting on new lands, ameliorations in agriculture, and above all the extended use and cultivation of the potatoe, have proved that many remedies besides emigration were capable of being applied, and of absorbing that popu- lation which was rapidly augmenting, and always trench- ing on the very verge (to say no less) of redundance. But the views of the partizans of these expedients were not sufficiently penetrating, and the instances adduced above are sufficient to show that the disease has advanced more rapidly than this class of remedies has been pro- vided to cope with it, and thus the question in favour of occasional emigration is determined. The fault has been one too /common in argument, that neither party has been inclined to yield enough to its antagonist*. I shall not be suspected of quoting Voltaire as an * It will be easily perceived that I here allude to the numerous writ- ings which followed the able essay of my noble friend the Earl of Selkirk. To the general principles laid down in that work we are indebted for the greater correctness of thinking which has lately been introduced into this branch of our political economy. But enough power was not granted in it to the system of removal, crofting, and general improvement. His opponents on the other hand have attri- buted too much to its efficacy, and have supposed it to afford a perpetual remedy for all future accumulation of people ; while they l)ave made the subject a source of controversy in a manner unfitting that which jieculiarly requires calm and temperate discussion. BENBECULA. — HIGHLAND POPULATION. 113 authority in political economy, but the subjoined passage is not inapplicable to the subject.* There is yet another question connected with the state of the insular population, of a political nature and of no small importance ; arising from the nature of the present tenures and the extreme division of farms in the unimproved islands. This seems limited to a narrow space as a question of government, and had this radical and proper basis of tlie argument so often and so acrimoniously contested among the numerous disputants, been suffi- ciently regarded, less time would have been occupied by the controversy. There is no doubt that the popu- lation of any country like this will be greater under such a system than under one which shall convert many small pastoral farms into a large one, or which, by uniting in a similar manner the small arable farms, shall dispense with the numerous incumbents who under such an improved system would find no employment on the soil. But in these cases the same quantity of the given manufacture, cattle or corn, is produced by fewer hands, or the agricultural machine is more perfect. And as the perfection of agriculture, as of manufactures, is that state in which the greatest produce is obtained at the least expense, it would be difficult to admit the principle that this perfection in the first of all arts was advan- tageous in a general view, while in the details it was injurious. Where each cultivator can only produce suffi- cient for his own maintenance he can pay no rent : where he can produce but little more he can pay but little rent, and thus rent is in some measure the criterion of agricultural improvement. But where he produces no more than he consumes there is no surplus produce ; * " Dans ge cas il faudroit que la terre. rendit le double de ce qu'elJe rend, ou qu'il y auroit le double de pauvres, ou qu'il faudroit avoir le double sur I'etranger, ou eiivoyer la nioitie de la nation en Ameriquej ou que la moitie de la nation niangeat I'autre." VOL. I. 1 114 BENBTCULA. HIGHLAND POPULATION. and in this case there can be no surplus population ; no army, none of all the classes which constitute the efficient parts of a state. Here then is the basis of the argument as far as it respects this question. It is true that the individuals living under such a system may be very innocent, and very contented, but the collective society cannot exist on these terms, and it is equally plain that whatever portion of it is in that condition, is, for the general purposes of the whole, useless. Since it can furnish no food, it can supply no members for that part of the society which is the bond and security of the whole, that which governs, thinks, and defends. Where this state also exists, the limit to population must consist in distress or in absolute want, since no one will change his place from any other motive ; and thus the change of place is preceded or attended by a state of poverty or incon- venience giving to the emigration that character of misery which has occurred so often that the idea of dis- tress is necessarily connected with the word, and in the minds of the mass who are not accustomed to examine the associations of their ideas, appears to be a result of it. Dismissing this subject, which would otherwise ramify into digressions inconsistent with the nature of this work, it is interesting to examine whether the agricultural con- dition of the Highland districts in question is not a prac- tical illustration of the political principle just mentioned, namely, that such a state admits of no surplus popu- lation ; this being the great point as far as government, or the general benefit of the whole empire is concerned. Like many other popular opinions, repeated without examination because once asserted, the Highlands, and these islands among them, are represented as a nursery of seamen and soldiers. Montesquieu has well remarked " Qu'il y a des choses que tout le monde dit parce qu'ils out ete dites une fois." It is said even in recent writings, that the islands furnish some thousands of soldiers to the service, ' BENBECULA. HIGHLAND POPULATION. 115 and the statement is always adorned with an eulogium on the militaiy character and the mihtary propensities of the natives. The character of those who are soldiers admits- of no ques- tion, but it must not be made use of to cover an unfounded assertion respecting their mihtary propensities. They are every where notedly averse to the army, and I do not say without abundant information that it probably would be impossible to raise a single recruit by beat of drum, or a single volunteer for the navy, throughout the islands; more particularly in those where the population is the most crowded and most needy ; in other words where the ancient habits are most prevalent. It is doubtful if the whole of the islands possess at this moment an hundred men in both services. Sky with a population of at least 16,000 has not a man in the army. The same is true of Arran, less remote yet equally under the influence of the ancient system.* It is not here meant that the effectual demand for labour in the islands is such as to prevent any part of the population from being removed for military service without detriment to the agriculture. Far from it, but the practical result is the same, and it arises from tlie divided and universal possession of land. Recruits are never easily obtained from agricultural labourers, for reasons well known, and still less can they be procured among those who are the possessors or the occupiers of land, be those occupancies ever so small. If recruits should be raised in the islands they would be found in Isla, not in Sky, nor in the Lono- Island. This is a condition of society in which military conscri'ption becomes, in cases of need, imperious, since no other mode of forming an army remains ; and the example of France, in which so large a portion of the land became occupied in a similar manner in consequence of the revolution and its events, while it illustrates the present case, justifies the necessity of the measures there adopted. * Since this was written the agricultural system of Arnm has been cliansed. — 1818. 116 BENBECULA. GEOLOGY. Tt may truly be said that the population of 60,000 Highland insulars, which according to the ordinary average of European militaiy supply would have afforded 600 soldiers, was defended during the late war by the artisans and manufacturers of England and the low countiy. The adoption of means to diffuse the spirit of military and naval service throughout these islands would in many respects confer a decided benefit upon them ; not only by affording an useful drain on the population, but by making an inroad on many of those habits which are the ground- work of the evils enumerated. At the same time, the return of disbanded men would have the effect of intro- ducing improvements, which on so many occasions have been the result of similar circumstances. To inquire why this is not done, would be to inquire why so much of that which relates to the improvement, the police, and the general welfare of these islands has been neglected. But it is time to return to the physical history of Benbecula. As I have already remarked that the islands of Grimsa and Wia resemble Benbecula in every respect, it is unne- cessary to give any further description of them. That of the one will serve for the whole, as well in the general as in the geological characters. I may only observe, that some parts of the shore of Grimsa exhibit beds of gneiss of extreme tenuity, micaceous, and capable of being detached in thin leaves. The whole composition of Benbecula is identical, and consists entirely of gneiss, forming in reality a continua- tion of the rocks of South Uist. This gneiss is found occu- pying the whole of Benbecula hill, as well as almost all the coasts and islands that I examined, and all the pro- tuberances which are scattered over the face of the country. The only exception will be noticed immediately. Its character is as various as that of South Uist and Parra, and it would be difficult to say that any one BENBECULA. GEOLOGY. 117 modification was predominant. In one instance only I perceived a rock traversed by minutely ramifying veins of trap, of a compact basaltic nature like those before described. The hornblende schist which appears, in a geological sense, to belong to this rock, is found in very distinct forms, and a bed of it on the summit of Benbecula hill abounds in garnets. Some specimens are also cha- racterized by containing greenish foliated talc. The exception above noticed is the following. At the entrance of Loch Kyleswiaveg are some islands composed of a schistose rock of a very peculiar character. It appears at first sight to be an intermixture of common blue argilla- ceous schist with grains of quartz and compact felspar ; a more minute examination proves it to be an irregular and very anomalous compound. But as this rock forms an important feature of the adjacent land of North Uist, and will require to be more fully considered hereafter, I shall defer any further notice of it at present ; remarking only, that it may possibly occupy some more of the outstanding islands, or skirt some of the shores which I could not inspect. 118 NORTH UIST. — GENERAL DESCIIIPTION. NORTH UIST. This island is the northernmost of that division of the Long Island which is made by the sound of Harris ; bearing at the same time many physical marks by which it is dis- tinguished from the remainder of the chain northwards. It is of an irregularly rounded triangular shape, its greatest length being sixteen miles, and its greatest breadth about thirteen. It is separated from Benbecula by a narrow, complicated, and shallow strait beset with innumerable islands, similar to that by which Benbecula is divided from South Uist. This strait affords passage for small boats, but only at high water, the sand called the north strand being fordable at the ebb tide. The sound of Harris, which boimds it on the north side, is seven miles in breadth and crowded with islands and rocks ; being passable by large ships, but not without the assistance of experienced pilots, there being no marks to point out this very intricate and dangerous channel. Some small islands skirt the western shore at different distances, but the eastern, as is usual in the Long Island, is abrupt and tolerably free from rocks and islands. Retracing the general aspect of the islands already examined, it has been seen that the chain from Barra Head as far as the southern point of South Uist consisted of an irregular group of hills, occupying both the western and eastern shores, and occasionally intersected by small valleys. In South Uist the groups of hills occupy the eastern side exclusively, while the whole western division pre- sents a level surface of peat, terminating to the west in sand. Benbecula presents an almost uniform flat surface, with the exception of one low hill, and the small elevation of Wia which may be reckoned as a constituent part of it. The surface of North Uist, although similar in its general NORTH UIST. GENERAL DESCRIPTION. 119 character, is differently disposed. On its eastern side, towards the north and near Ba Chaas, it rises into a low ridge, which gradually increasing in elevation towards the southern end on the same side, terminates at Heval ; this being the highest land in the island, and attaining, at the utmost, an elevation of 2000 feet. This chain is twice inter- rupted, namely by Loch Maddy, and by Loch Evort ; but may be considered as continued in Rona, an island sq exactly resembhng North Uist as almost to preclude the necessity of a separate description. Proceeding westward from the ridge of Heval, a large flat presents itself, so per- fectly similar to the eastern side of Benbecula that it is difli- cult to distinguish the one from the other. This tract, com- prising nearly half the area of the island, is apparently so equally occupied by land and water that the eye can scarcely determine which of the two predominates. While the superior brilliancy of the watery surface would per- haps cause us to assign it the largest dimensions, measure- ment will I believe, determine in favour of the land. In point of value with respect to vegetable produce, it will be found that the difference is much in favour of the water. Such is the surface of the flat eastern land of North Uist j a brown, peaty, and boggy tract so interspersed with lakes and rocks as to be nearly impassable, and producing a scanty and wretched herbage for a few animals during the driest months of summer, while in the winter it is resigned to wild geese, ducks, and swans, who divide its waste and ,wateiy region with the sea gulls which the ocean can no longer protect or feed. The water which thus occupies the flat interior tract of North Uist, is principally fonned by the ramifications of Loch Evort and Loch Maddy, together with those of minor extent which belong to Loch Macfail. Interspersed among these are numerous fresh water lakes and pools, of which some are inhabited by trout, and others, subject to occasional communication with the sea, are the temporary resort of salmon. The sinuosities of the sea lochs may be conceived from this iiO NORTH UIST. — KELP MANUFACTURE. stateiTient; that while the whole of Loch Maddy is com^ prised within an area of nine square miles or less, its shores have been found by measurement to extend two hundred. These shores abound in those Fuci which are used in the making of kelp, the annual produce of this inlet alone being 300 tons. The cutting is chiefly triennial, and the quantity of sea weed required to produce this proportion of kelp is upwards of 7200 tons. Loch Evort covers a space nearly equal to that occupied by Loch Maddy, and its sinuosities are equally remarkable. Having mentioned the kelp of Loch Maddy, I may extend the remarks on this manufacture for a few lines ; since it is almost the only one which may be said to exist in the islands, and since its establishment, although but recent, has made so material an addition to the value of these estates, and to the demand for labour. The total produce of the Western islands in kelp varies from 5000 to 6000 tons, of which two thirds are the produce of the Long Island ; the result of its highly indented shores, and of the consequent extent of surface, as well as of the superior tranquillity of the waters in which the plants grow. The variations in the price of this article, resulting from the varying competition of foreign commerce, are very considerable ; and as the total expense of manufacture has been estimated on an average at £5 per ton, a considerable deduction must, in calculating the profit, be made from the market price, which at the time of my last visit was £10.* A great increase in the supply of foreign barilla, or the discovery of the long attempted problem to decompose sea salt by a cheap process, would destroy this most precarious source of profit; since the interests concerned * That price has occasionally varied even to £. 30, causing differences of serious amount in the value of these estates. NORTH UIST. KELP MANUFACTURE. 121 in it are too few, and the total advantages too insig- nificant, to claim the protection of restrictive laws. In general, it may be remarked, that the kelp is reserved by the proprietor, and manufactured on his account; a very questionable piece of pohcy in some points of view. A large portion of the population is employed for the three summer months in the manufacture, which is so laborious and severe as to have no parallel in this country; certainly at least, not at the same rate of wages. This labour has been called compulsory, and in one sense it may be considered a servitude, since it is generally the condition of tenure and either the whole or a portion of 'the rent by which the tenant holds his farm. If he were a free labourer, it is often said, he would not engage in so disagreeable a task. But this, although abstractedly a painful view, is a false one, and is unjust as it regards the proprietors of estates; though casual visitors may be sometimes in- clined to think that Highland proprietors have not yet forgotten their ancient habits of unrestricted sovereignty. It is a case of competition, and is the natural resvilt of excess of population, combined with the absence of that proper and necessary division in an agricultural system which creates a class of independent labourers. The tenant must pay a fine for his farm, and he knows the price which he has to pay. That rent which he cannot procure by his surplus produce, he must pay by his labour, and as the system does not admit of a steady demand for work, he must labour when he can obtain it. An efficient and steady demand for labour might indeed affect the rate of wages, but it would scarcely leave the labourer the choice of refusing to work in the manufacture of kelp when called on. He might imagine himself free, his wages might possibly be greater, but still he must work wherever there is work for him. It is plain moreover in this case, that as the surplus produce of his farm does not enable ]22 NORTH UIST. KELP MANUFACTURE. him to pay the rent, and he must find the money for it by his labour, no advantage is gained if he is merely to repay the money with one hand which he has re- ceived in the other. He may in fact be considered as a cottar, subject to the calls of his employer, not so well situated perhaps, yet still as well as the state of the countr}' admits. It is even to be doubted whether, in many cases, any thing short of this apparent com- pulsion could overcome the natural indolence and aversion to labour which, from whatever causes, is a strong feature in the character of the unimproved Highlander. As far as relates to the details of this manufacture, they seem to have been for some years past in a state of rapid improvement, and to have attained on many of the estates, in consequence of the attention of the proprietors or their agents, all the perfection of which they are susceptible. The time occupied in it, as I b.efore remarked, is about three months, namely June, July, and August. Drift weed, thrown on the shores by storms, and consisting chiefly of Fucus digitatus and saccharinus, is used to a certam extent when fresh and uninjured, but the greater part is procured by cutting other plants of this tribe at low water.* The differences in the dechvity of the shores therefore, as well as in tiieir hnear extent, and the gi'eater or less rise of the tide, together with more or less shelter from the pre- valent surge, constitute the chief bases of the variations of a kelp estate. Soda is well known to abound most in the hardest Fuci, the serratus, digitatus, nodosus, and vesiculosus. On some estates they are cut biennially, on others once in three years, nor does it seem to be as- certained what are the relative advantages or disadvan- * The method of landing the weed after cutting is simple and ingenious. A rope of heath or birch twigs is laid at low-water beyond the portion cut, and the ends are brought up on the shore. At high water, the whole being afloat together, the rope is drawn at each end, and the included material is thus compelled at the retiring tide to settle on tlie line of hieh-water mark. NORTH UIST. — KELP MANUFACTURE. 123 tagea of these different practices. The weed is burnt in a coffer of stones, a construction which, however rude it may appear, seems fully adequate to the purpose. Attempts have been made to introduce kilns of a more refined construction, which have failed from the most obvious cause, the expense of fuel necessaiy for their support; the inventors appearing to have forgotten that the substance in the ordinary mode of treatment formed its own fuel. The number of these fires which during summer are for ever burning along the shores, give an interest and a life to these dreary scenes ; re- calling to the spectator's mind the activity of society in regions where all other traces of it are nearly invisible. The poet who indulges in visions of the days of old, may imagine the lighting of the war-fires, and fancy he sees the signals which communicated the news of a Danish descent through the warlike clans. The quantity of sea weed required to make a ton of kelp is estimated, as I have already noticed, at 24 tons, but varies according to the state of its moisture, and hence a conception of the labour employed in this ma- nufacture may be formed, since the whole must be cut, carried on horses, spread out, dried, and stacked, before it is ready for burning. It is a subject of frequent dispute w^hether the estates would gain more by the conversion of this material into manure, than by the kelp manufacture, but it is a question of too complicated a nature to admit of a ready answer. If it be admitted, as I believe the fact is, that there is at present a sufficiency of this and other manure already at the disposal of the small cultivator, the question is fruitless. If it be .supposed that the mere diversion of the whole sea weed to the land would brine: a larsfer portion of that into cultivation, it will then be easy to put the question, and to enter upon the calculations necessary to answer it. But this is not a correct view of the case. A different distribution of capital, population, and em- 4 124 NORTH UIST. KELP MANUFACTURE* ployment is required before larger tracts of land can be effectually improved ; and the diversion of the sea weed to this purpose is but a small part of that which is re- quisite to effect this object. When such alterations shall take place in the state of capital, population, tenures, and the division of lands, as will doubtless arise in the gradual course of improvement, it will be time enough to examine this question ; and the solution will probably not be very difficult. In the mean time, while there is no such demand for it existing, and while the price of labour, however that labour be obtained, is such as to render it an object of profit to the landholder, it is futile to say that the making of kelp is not of advantage to the com- munity. As a manufacture it furnishes employment to a half-employed population, and forms therefore a steady addition to its means. What remains of the argument respecting the relative claims of kelp and agriculture on the sea weed, must necessarily be a mere question of the market price of the former compared with the price of production. But another doubt has been started, of a more refined nature and of far less easy solution. It has been asserted that from short sighted views respecting the profits of this manufacture, the proprietors have imagined they had an interest in a crowded population, by means of which the wages of labour were lowered^ and a ready supply of it reserved for the purposes of making kelp. The consequences of such a policy, if it exists, would be to lower the rent of land as well as the price of labour, since a superfluous tenantry is here identical with an inadequate rent*. In this way, * As this proposition appears to contradict the common axiom respecting the effects of competition, it is proper to explain the cause. There is a point where, in this country, it ceases to have its usual effect and beyond which that effect becomes negative. From extreme subdivision arises bad cultivation, land imperfectly stocked, bad live stock, and consequent general poverty and inability. This result. NORTH UlST. KELP MANUFACTURE. 125 the landlord who is proprietor of the land as well as the kelp, would lose on one side what he might gain on the other. It is plain, that if the two properties were separate, the kelp maker would have a correct view, of his OAvn interest at least, in wishing for a crowded population, which, as far as they are separated, he actually has. Whether the proprietor of both has or has not is a mere question of contingency. In him, the practice of crowding the population, admitting it to be a fact, is a mere commercial speculation in which he sacrifices a given sum in the shape of rent, for the contingent ac- quisition of another in the shape of profit on kelp. He cannot well be so blind as not to perceive that he is paying the price of labour in two distinct shapes, and it is clearly his interest to ascertain the price at which he is the manufacturer of the merchandize in which he deals. If his avarice or his ignorance are such as to render him a loser by his speculation, it is scarcely a subject for the interference of others : hke other spe- culations it has a natural tendency to rectify itself if wrong, and must be left to that freedom which ought alone to direct all the movements of commerce. It wdll I believe be admitted by many of those who are ac- quainted with these islands, that there are tracts of land now occupied by small tenantry at an inadequate rent and under inefficient management, which if well managed would return a considerably greater profit to the landholder, and possibly exceed that which under the present system he makes by his kelp. But the changes required for this improved management of the land are such as cannot occur under the present state if it were not every where apparent, would be proved by the increase of rent wliich has followed the consolidation of small farms, or, a diminution of competitors, such as these small competitors are. It is besides obvious, that the landholder who would increase his population for these ends, can only do it by offering his land on better terms than his neighbours. 1^5 NORTH UIST. — SOIL AND SURFACE. of population, if we consider either its number or dis- tribution. To produce these changes by violent mea- sures is difficult, as various attempts have proved ; were we even to leave out of consideration tlie painful moral effects which follow all those sudden and violent changes that operate on the state of population in a country. The changes have however commenced, and they cannot fail to spread. For the total benefit of the community, it is to be desired that they should, but it is also to be wished that they should take place with the least possible inconvenience and suffering to those who nlust, to some extent at least, be displaced. When the land shall have been raised to its adequate value, and to the state of improvement of which it is susceptible, a class of independent labourers will naturally arise to accompany the change ; and the manufacture of kelp, which has perhaps already been dwelt on too long, will be subjected to a new calculation. But to proceed to the description of this island. Three distinct gToups of hills occupy the western side of North Uist. The northernmost of these consists of a tame ridge bounding the sound of Harris, of which Ben Breach and Ben More form the chief eminences. The highest of these scai'cely attains to 1000 feet. In the middle of the western division is found a second group, of which Croghan is the principal eminence, at- taining to all appearance a height of 1500 feet, while the south western side terminates in a prolonged and irregular gi'oup of much lower elevation and of a smooth undulating surface, gradually declining into an uneven tract of good land. This forms the principal part of the arable land in North Uist, and is, in an agricultural view, the most profitable. The soil contains clay, a rare occurrence in this tract of country, and this by aid of the peat that in a greater or less degree predominates NORTH UIST. SOIL AND SURFACE. 12/ throughout the island, and with the addition of sand from the shores, forms an excellent mould. Much of the western shore consists of the same drifted sand which is so abundant in the islands to the south of this, and which, mixed with the peat in various pro- portions by its natural tendency to spread over the country, forms a light open soil applicable to the cul- tivation of barley and potatoes, particularly when ma- nured, as is the practice of the country, with drift sea weed. The remainder of North Uist, comprehending the hilly region and the watery tract, is a mere mass of peat, producing little but the heath, rushes, and scanty grasses usual in similar soils, except in a few spots where by the assiduity of the small tenants or crofters, it is rendered capable of yielding an occasional crop of barley or potatoes. The peat in this country is in general of considerable depth, reaching from ten to twenty feet downwards, and almost always incumbent on a body of alluvial gravel, or on the bare rock. In some situations it is found to repose on a bed of fine and soft, but not tenacious, pale greyish clay, which on burning is con- verted into a white powder, and applied by the natives to the purposes of scouring or polishing metallic utensils. It is a porcelain clay resulting from the decomposition of the felspar in the gneiss. Tlie peat of North Uist, as well as that of many other parts of the Long Island, is in a state of extreme decomposition at its lower parts. On this account it forms when dried a compact substance of great density, which is incapable of being again affected by exposure to rain, and which requires therefore no protection when completed. Its specific gravity is much greater than that of ordinary peat. It burns with so bright a flame as to supersede the necessity of light in the cottages of the natives, and with a glow of heat equal to that of the inferior kinds of coal, while it is capable of 128 NORTH UIST. PEAT. being formed into a compact charcoal fit for the pur- poses of the blacksmith. The introduction of a few remarks on the formation of this substance will hardly be deemed to require excuse, as it is a question in- timately connected with geology. The subject has indeed been so frequently examined that but little remains to be said on it : had less been written it would not perhaps have so often been in- volved in unnecessary obscurity. Agriculturists have distinguished it into several varieties, partly determined by its situation, and partly by cor- responding changes of texture. It is not necessaiy to follow them further than merely to remark, that ac- cording to the nature of the substratum, the drainage or lodgement of water to which it has been exposed during its formation, and the plants which enter into its composition, it presents differences of aspect, with some slight variations in its chemical qualities; the latter corresponding to the extent of change the con- stituent vegetables have undergone. In general it forms but a single stratum bedded on the rock, or on the alluvial matter above. Occasion- ally however it is found alternating with sand, clay, gravel, or shell marie. The latter alternation is the most remarkable, and occurs only when the peat has been formed under water, or when, after the drainage or extir- mination of a lake, it has grown above the decomposed mass of fresh water shells which occurs in those places. The former alternations occur either from the blowing of sand on the sea shores, or from deposits of alluvial matter brought down by mountain torrents. Although fragments of trees are frequently found buried in it, these are not essential. They must be considered as accidental substances, and occur in those cases where it has been formed in forests, partly from NORTH UIST. PEAT. 129 the decomposition of their fallen leaves, partly from that of the plants which grew under their shade. Oak, fir, alder, and birch, are the woods most frequently found, and it is almost unnecessary to say, that the remains of animals and other accidental substances are occasionally buried in peat. The plants which by their destruction contribute to its generation, vary according to the situation in which it has been formed. In any one situation some species are more abundant than others, from circumstances too obvious to need enumeration. It has often been asserted that Sphagnum palustre is the true basis of peat : this how^ever is an unsupported opinion. Doubtless, in peculiar boggy situations it forms a predominant ingre- dient, but large tracts of peat may be found in manv places where this moss never grew. * The process by which these vegetables are converted * The following list contains the plants that mnst Trequently concur to the generation of this sulistance, and they are placed with some regard to their importance: — Sphagnum palustre. Scirpus coespitosus. Nardus stricta. Scirpus palustris. Juncus conglomeratus. effusus. Eriophorum polystachion. vaginatum. Schoenus nigricans. albus. Erica tetralix. . cinerea. vulgaris. Myrica gale. Juncus bufonius. bulbosus. Agrostis canina. Aira coespitosa. Pedicularis palustris. Orchis maculata. VOL. I. Carex dioica. pulicaris. flava. panicea. coespitosa, and others of this genus. Anagallis tenella. Menyanthes trifoliata. Comarura palustre. Empetrum nigrum. Ranunculus flammula. Scirpus acicularis. Nymphoea alba. lutea. Potomogeton natans. Drosera rotundifolia. Juncus squarrosus, besides others, many of them of such rare occurrence as not to deserve enumeration. 130 NORTH UIST. PEAT. into peat is very obvious, and the consequent increase of that substance is easily understood, v.ithout endowing it, as has been often done, with hving powers. It is most easily seen in the Sphagnum. In this, as the lower ex- tremity of the plant dies and is decomposed, the upper sends forth fresh roots, like most of the mosses ; the individual thus becoming in a manner immortal and sup- plying a perpetual fund of decomposing vegetable matter. A similar process, although less distinct, takes place in many of the rushes and grasses; the ancient roots dying- together with the outer leaves, while an annual renovation of both perpetuates the existence of the jilant. Other vegetables again add to the common stock by their annual death, their existence being repeated in seedling plants ; while others still, of a perennial nature, contribute only by the ordinary decay and renewal of their leaves and flowers. The progress of this decay, the gradation from the living vegetable to solid inorganic peat, is generally easy to trace. Where the living plant is still in contact with it, the roots of the rushes and hgiieous vegetables are found vacillating between life and death in a spongy half decom- posed mass. Lower down, the pulverized carbonaceous matter is seen mixed with similar fibres still resisting decomposition. These gradually disappear, and at length a finely powdered substance alone is found, the process being completed by the total destruction of all the organized bodies. If this process has been carried on upon a drained declivity, the result is a loose powdeiy matter, namely, heath soil, or mountain peat ; if in an inundated or wet soil, it is a mixture of that powder in the water, or the flow moss of agriculturists. Intermediate circumstances produce intermediate conditions, and thus many varieties of peat are the result ; while all these are further increased by differences in the vegetable ingre- dients, in the time dui-ing which the process has lasted, in the degree of drainage, and in the elevation or other NORTH UIST. PEAT; 131 causes affecting; the temperature or moisture of the atmospliere. The properties of peat as a fuel vaiy accord- ing to those circumstances ; the best being that of which the decomposition is most complete and the specific gravity and compactness greatest. Such is the case in that of North Uist which has given rise to these remarks. As the growth of peat necessarily keeps pace with that of the vegetables from which it is formed, it is evident that the cessation of the one is implied in that of the other. Hence the necessity, now at length understood, of re- placing the living turf on the bog whence peat has been cut ; a condition now required in all leases where liberty to cut it is included. No vegetable seems willingly to attach itself to pure peat ; and thus a bog once bared to a sufficient depth remains naked : where the decomposition is but incipient, the process of vegetation is renewed and continued without difficulty. The solubility of peat in water varies according to the degree of vegetable decomposition: pure peat communi- cates no stain, and the brown water that contaminates the rivers of the Highlands is derived from it in the incipient stage of the process. The cause of this will appear from considering the nature and progress of the chemical changes; on which I shall bestow but a few words as they are abundantly simple ; although, like the rest of the history of this substance, much misunderstood. If recent vegetable matter be distilled carefully by a red heat, it is converted into charcoal, acetic acid, and an oil varying in density according to the stage of the process, together with an occasional small quantity of ammonia. No inflammable gas is produced but by mismanagement of the operation. It is unnecessary to describe these results more particularly, as I have treated of them at some length in the 2d Vol. of the Geological Transactions. There is in this case a certain proportion between the coal and the oil. This latter substance, under its various modifications of pitch, tar, or essential oil, is 132 NORTH UIST. PEAT. compounded principally of hydrogen and carbon. Now if peat be subjected to the same process we obtain the same results but in different proportions. The acetic acid is diminished and the oil bears a smaller proportion to the charcoal, that proportion diminishing gradually according to the perfection of the peat. Consequently the chief effect of increasing decomposition in the peat is to diminish the proportion of the hydrogen to the carbon in the vegetable compound, of which these are the principal con- stituents. The effect of water on the vegetable fibre is therefore similar to that of fire, although less perfect; since^ after the last efforts of the former substance, a considerable portion of hydrogen remains combined with the carbon ; even in the lignites, of which the changes are more com- plete than those of any peat with which we are acquainted. In the incipient stage of the action of fire, the compound of carbon and hydrogen is partially soluble in water, a familiar example of which occurs in the roasting of coffee, and the same takes place in the conversion of vegetables into peat. In each case when the proportions of these two constituents have attained a certain ratio the compound is no longer soluble. The simple principles thus laid down seem to contain every thing requisite to explain the chemical nature of this substance, and I shall not therefore pursue them further. They will serve to unravel and reconcile many obscure and contradictory experiments, and in pointing out the causes of the varieties of peat, assist agriculturists in their pursuits by directing their attention to the essen- tial differences.* I have had occasion to observe in the island now under * It must be obvious, that the conversion of peat into soil will be dif- ficult in proportion to its perfection; since independently of its greater compactness, it approaches more nearly to the stale of charcoal, bearing, to imperfect peat, an analogy resembling that which effete does to recent manure. Hence also a hint may be derived respecting the conduct of that process by which the manure called the Moadowbank compost is formed. NORTH UIST. PEAT. 133 review, us well as in South Uist, that peat is sometimes luminous, a phenomenon analogous to that produced by wood in a certain stage of decomposition. This fact is, I believe, also noticed by some oriental traveller. There appears to be great variety in the time which a given mass of this substance requires to accumulate ; as might indeed be c6njectured from the various energy of vegetation in different situations. Two or three registers of time are to be found in this country, in the dates of substances lying beneath it, but they can only be considered applicable to the particular places where they exist. A Roman road is found on the clay under Moss Flanders in Stirlingshire, a raft of squared timber having also been discovered in the same place. The peat here varies from twenty to forty feet in depth. A road formed of logs of wood was also found under Kincardine moss, together with felled trees laying on the clay substratum, these being probably of the same date with the former. In more recent times Camden has described the park which now lies under Chat moss near Liverpool, and the palings have been recently found in digging into that spot. But it is not my design to enter further into this subject. Yet it will not be out of place, after this veiy slight sketch of the nature of peat, to bestow a few words on its economical details as applied to tlie purpose of fuel, of which it forms the sole article in these islands. The consumption is unavoidably great, since, independently of the constant demand for cookery, the moisture of the climate renders fire almost as necessary in summer as in winter. Although the total supply may be considered, in a general sense, inexhaustible, some of the islands labour mider serious inconveniences from the want of it. Tirey, Canna, lona, and Muck, are in t!iis predicament; which adds considerably to the expense of the tenant, and consequently detracts from the value of the land. A commercial arrangement which should supply these islands 134 NORTH UIST. — PEAT. with coal from the western parts of Scotland, would tend much to their improvement ; but it is at present, under the existing division of farms and the consequent want of a constant and regular basis of exchange, impracticable. It is indeed a case parallel to those which must always happen in countries similarly divided, similarly peopled, and where there is no steady demand for labour ; where consequently no occupations exist by which an exchange- able commodity can be generated. If it is true that the price of peat in Tirey is five times that of coal, when the charges of procuring it are considered, it is equally to be remembered that the labour now employed on that object has at present no other adequate vent; and that its value must be estimated, not as it is thus em- ployed, but as it would be employed if it were not directed to that tedious and laborious occupation. The price of peat may thus in certain extreme cases be perhaps nothing. The same argument applies to a proposal which has been made, to establish in the Long Island, where the peat excels both in quality and quantity, a manufacture for tile purposes of a general supply, and ,to reduce it to a distinct occupation. Could such a manufacture be established, it is plain that the consumer must find something to give in exchange, and it is not difficult to see that the inferior price and superior quality of coal, conjoined to the activity of an established com- jnerce, which is always ready to create a new market wherever there is an opening, would soon drive the peat competitors out of that market. Like most other established systems, that of the Islands, if it be bad, is at least con- sistent ; and, like those, its bearings are so numerous, that he who attempts to repair a part without a regard to the connexions which it has with the whole, will act like a legislator who should attempt to leform New Zea- land by introducing the Statutes at large. Jt is not that improvements cannot be compulsory : the fault is, that the improver takes too narrow a view of the bearings 4 NORTH UIST. — ALLUVIA. 135 of the evil, and of those of its remedy : while he is damming the stream at one aperture, it escapes him at another; such is the slippery nature of political economy. The labour of making peat is in truth an evil which it would be most desirable to see remedied ; since it occupies a great portion of the summer, employs many hands in the making, and many animals in the carriage ; while even all the labour which can be commanded is sometimes insufficient to procure an adequate supply. It is estimated at a third of the total expense of the farm; an estimate probably in some cases not beyond the truth. In this island however, and generally through the Long Island, the vicinity of the peat, together with its compact quality and goodness, renders it a nmch cheaper article. Having mentioned alluvial gravel as being found under the peat in North Uist, I may proceed to remark that considerable alluvia are to be observed on the surface in various parts of this island ; considerable at least, when compared with their almost total absence in the southern islands of the range. These are independent of any present flow of water, and are found either occupying the declivities of the hills, or forming small elevations over different parts of the surface. They are accompanied by an occasional decomposed state of the rock, an occur- rence, as we have seen, scarcely to be remarked in the southern islands, and one, from which have undoubtedly arisen the deposits of clay and soil already mentioned. This indeed is not the only circumstance that marks in North Uist the action of causes which the southern islands appear to have escaped. A group of small islands lies in the entrance of Loch Maddy, the nearest of tliem being a mile from any shore, and the sea which separates them varying from seven to fifteen fathoms in depth. Yet on the surface of some of these is accumulated a thick bed of alluvial clay and rubbish ; sufficient 136 NORTH UIST. SAND. to mark their former connexion with some liigher tract of land, and to serve as a record of those changes which have hollowed the sinuosities of that loch. I need not enter on the probable causes of these changes, as they have been often discussed, and as in describing the island of StafFa, which exhibits a remarkable example of this nature, every thing is said which occurs on the subject. I may only remark, that the alluvial matter and the rolled stones which are seen in these islands, are all equally the produce of the islands themselves, no boulders of granite, except fragments of the granite veins, being any where found among the substances scat- tered over their surfaces. Having repeatedly mentioned the accumulations of sand which occur on the western side of this tract of insular land, and which are as prevalent in North Uist as in the islands that lie to the south, it appears necessary to describe more particularly their nature and progress, as far as it is possible to decipher that progress, often very obscure. This is a phenomenon with which geology as well as agriculture is concerned, since these accumu- lations, which tend at times to fertilize and at others to overwhelm and destroy the soil, may also lay the founda- tions of beds capable by future changes of being converted into strata of marie, or, ultimately, even into limestone. The sand thus accumulated on the western shores of this land, is formed for the most part of various com- minuted shells, of which however only fragments can be obtained ; insufficient to show the species from which they have originated. Such shells in their living state form beds, as the sounding Une testifies, skirting the eastern shore; fine shell sand as well as clay being also found at different depths along the coast. In some places, as in Barra and Vatersa, this sand seems to consist of shells only, while in North Uist as well as in other parts, a portion of quartz and hornblende, the result of the wearing of the rocks, is mixed with the calcareous; matter. It is not easy to perceive the exact mode in which the NORTH UlST. — SAND. 137 sand proceeds,, nor the precise changes whicli take place in consequence of its movements ; changes which, ac- cording to some reporters, consist in a loss, according to others in an acquisition of land. It will probably be seen, that both are occasionally in the right, the loss of one party being often the gain of another. When the actual appearances have been described, some judg- ment of this question may perhaps be formed. The flat sandy shore which the tide alternately covers and deserts, is succeeded by a tract of loose blowing sand, interspersed with hillocks and broken banks of the same materials, slightly compacted by the roots of the Triticum junceum, Carex arenaria, Gahum verum, Anthyllis vulneraria and other well known tenants of similar soils. Beyond this, in the interior, the sand is irregularly diffused over the surface, according as the forms of the ground admit of the free progress of the wind, or oppose obstacles to its motion. Continuing to spread, it becomes more and more intermingled with the peat or other natural soil, forming mixtures of dif- ferent degrees of fertility. Wherever a sandy bed is perforated, a foundation of peat appears. If now we examine the sand hills which form the second zone here described, we shall find them more or less perfect. In many cases they have nearly disappeared, leaving only pillars or fragments remaining to prove their former altitude, which often reaches to twelve or fifteen feet and even more. The mode in which the sand hills waste is apparent. If a hole be made, or a turf removed from the surface, the wind gradually enters it, scooping out the loose sand, until, in the progress of years, the whole is mouldered away and transferred to a more distant point from the sea, where it is diffused over a wider surface. Thus in North Uist, as well as in other places, we trace the ruins of elevated banks now nearly reduced to the level of the shore ; and here the spectator, like the tenant of the farm, is ready to imagine that the 138 NORTH UIST. — SAND. sea encroaches on the land. In another place, a tail of sand may be seen accumulating under the lee of a rock, or of a former bank, or of some other protecting obstacle which, by checking and retaining the land water, and thus giving root to plants of a dense growth, or by en- couraging the growth of the common sand plants, gradually causes it to increase all around, repelling the sea and forming a new bank, the foundation of future fields. Here the land gains on the sea. It is probable that the gain and loss are throughout this line of coast pretty equally balanced ; perhaps we should rather conclude that the advantage is in favour of the land ; since every sand hill removed by the winds was first brought from the sea, and there is no reason to think that the production of shell sand is diminished, or the power of the winds and waves in transferring it to the land abated. An admirable register both of the increase and diminution as now stated, may be seen in an ancient chapel situated at the north-west angle of this island, of a date, like the other antiquities of this country, unrecorded in history or tradition, and without architectural decorations from which to conjecture its sera. It has been erected at a time when the sand was at a level pretty nearly inter- mediate between the present lowest one and the highest, as that is marked by the remaining surfaces of the sand banks. This level is also indicated by the proportion of the walls. At a subsequent period it has been overwhelmed with sand, of which the record is also markied by numerous banks of a high level, one of which, to the leeward of the gable, still overto})s it, tailing away under its pro- tection at a height similar to that of the neighbouring banks. But the process of destruction long since com- menced at the windward side, has again denuded it even below the foundation in that quarter, the final removal of the bank being only impeded by the coffins, of v/hich the exposed surfaces are seen covering the ground, while tlieir contents are whitening in the wind and spray. NORTH UlST. — SAND. 139 Such are the appearances of the coasts, and such the nature of the revolutions which seem to have taken pkice on this shore. These changes appear, in an agricultural view, to counterpoise each other. By the progress of the sand into the interior, new surfaces of peat are ren- dered productive, and the arable extent of territory is on the whole increased. It is true that the advantages may be transferred from one set of tenants to another, since that sand which in its diffused progress fertilizes the more distant soil, may by its abundance suffocate the intermediate land over which it passes. The proprietor however gains, since the extent of reclaimed land will prove much more considerable than that of the injured, when we reflect that the predominance of water in the interior soil, renders useful that sand which, in the flatter and arid shores, is condemned to almost hopeless steriHty. I have been thus particular in attempting to elucidate this matter, because it is a phenomenon of common occur- rence, the right understanding of which may often be of considerable importance in agriculture. It is important also to show that the transference of sand, although in some cases destructive, is in others attended with advantage, particularly when, as in this instance, it con- sists of fragments of shells. It is also necessary in a geological view to attend to all those changes by which the state of the surface is altered ; of which changes none have been liable to more misapprehension than those which occur on sea shores. I have suggested the possibility of such accumulations of sand being ultimately convertible into marie, or even into limestone. There is in fact no apparent reason why the consolidation of such materials should not take place under the soil as in the sea. No appearances, I believe, have as yet occurred to geologists which either require, or would admit of such an explanation ; but such cases may be imagined, and it is in the mean time useful to register all those facts which may ultimately tend, even 140 XOllTH UlSr. ANTIQUITIES. by the remotest probabilitieis, to elucidate this obscure science.* In the account of South Uist and Barra, the want of springs and water courses has been noticed, and it was remarked that the lakes appear to be filled from the drainage water of the surface. The same remark, though in a somewhat less degree, is applicable to North Uist ; since its more numerous elevations give rise to a few small streams, which although not permanent, are more frequently filled tlran those of the southern islands. The vicinity of the mountainous land of Harris appears also to generate more rain in North Uist than is observed to fall in the southern division of the chain. In this island, as in many of the others, are found remains of military works now nearly obliterated. These, according to the predominant custom of the people eveiy where, are called Danish. The most remarkable are situated on small islands in lakes, but they present little but heaps of ruins. One of them which I examined, was connected by a raised causeway with the shore. It has been supposed by some antiquaries that the works situated in islands were actually Danish or Scandinavian, and that they were thus distinguishable from the similar fortresses of the British, which were supposed to be always * I have formerly noticed the gay appearance of the sandy plains which are prevalent in these isl;inds, and occasionally mentioned the most conspicuous of the plants wliich inhabit the pastures, of which the fragrance perfumes the air around. I shall here enumerate all the plants which 1 observed in a single green plain, a list which will, I believe, ajpply to the whole of this tract of country, as well as to the sandy shores of the other islands. Holcus lanatus, Bromus mollis, Festuca duriuscula, Agrostis littoralis, Festucaovina, Aira llexuosa, Aira praicox, Lolium perenne, \ icia cracca, Potentiila anscrina, Geranium sanguineuni, Trifolium repens, Thalictrum pratense, Bcllis |)oreimis, Ranunculus arvensis, I'lantago lanceolata, Anthyllis vulneraria, Galium verum. NORTH UIST. — ANTIQIJITIE.S. J4I placed on hills. But it is fruitless to discuss these ques- tions, since not a shadow of evidence can be adduced respecting them. It has been on all occasions found that there was a considerable resemblance in the manners, usages, warlike weapons, and monumental practices, of the original British or Celtic inhabitants and those of their early invaders ; and there seems no ground for attempting a distinction in the structures which they erected for the purposes of defence. Such a systematic distinction at least as that al)ove mentioned is little likely to have existed in rude nations whose immediate necessities were the spur to these undertakings : systems are the off- spring of refinement. Numerous barrows are also found in this island, and a group of them is still remaining in one of the sandy tracts of the north western shore, though many have doubtless been either overwhelmed or blown away, in consequence of the continual transference of the loose sand. Similar barrows are known to abound throughout Scotland as well as in South Britain, although the cairn of stones is, in the former division of the island, more prevalent than the tumulus of earth. Such memorials on being opened, have generally been found to enclose urns, sometimes further secured in stone chests and con- taining ashes, as well as trinkets, weapons of war, and other objects of affection or fashion; the burning of the dead appearing to have been a prevalent custom during the ages which preceded the introduction of Christianity. At times entire skeletons have also been discovered in them. Recently, one of the barrows in North Uist was opened during the operations of leveUing and clearing some rough ground, and was found to enclose a skeleton in an erect posture. As we have no records of such a practice as the interment of bodies in an erect position, it is probable that this was one of the hiding places which, till lately, are known to have existed in several of the islands. These subterranean apartments were used as places of retreat in cases of sudden invasion, 142 NORTH HIST. — GEOLOGV. and seem to have varied in construction. Sometimes tliejf were built of stones, being of commodious forms and of considerable capacity : in other cases a cavity in the shape of a well, lined with stone, and adapted to tlie size of the body has been discovered : while the rudest, to which the one in question seems to have appertained, were mere pits dug in the earth, and covered with turf for the purposes of temporary concealment. The unfortunate Celt above recorded, seems to have perished in his retreat during the heroic times of this envied age.* The reader who has followed these details through the islands already described, will doubtless still expect to find gneiss forming the sole rock of North Uist. Although this in a general sense is true, there is fortunately here some variety in the ridge of Heval, already mentioned as forming the eastern hilly margin of the island. Such variations give a necessary stimulus to the observer, * A perfect example of these subterranean retreats is found near Tongue in Sutherland. The external entrance is formed of large stones arranged in the same inclined manner as in the Pyramid of Cheops. This seems to have been the origin of the arch, a subject respecting ■which nmch has been written. Between this and the pointed Gothic arch the transition is indeed but small, the curvature of the two inclined stones forming the first stage of it. Some of the earliest structures of Greece present examples both of this modification and of that imme- diately subsequent, where a third stone fills the interval left at the apex. But I cannot here enter on a subject which is the province of archi- tectural antiquaries. It would require an essay to contain the evidence in favour of this view which might be derived from ancient architecture both European and Oriental ; and which appears to prove that the circular has been derived immediately from the pointed, or Gothic arch. It is obvious that the confusion of styles in the ancient architecture of England does not interfere with this argument, as it may be explained by supposing that the ecclesiastical builders drew from two distinct sources, the Roman and the Oriental ; an opinion supported by many collateral proofs. The pointed arch is of a much prior date to these buildings. The Sketch, PI. SO. fig. 3, will serve to convey a general notion of the transitions in question. NORTH UIST. — GEOLOGY. 143 whose ardour is apt to flag in searching for novelty which he is doomed not to find ; and they re-excite his languid endeavours to watch with renewed attention for chansres Avhich, though at tlie moment concealed from him, may possibly be on the brink of rewarding his labours. The ridge of Heval is an Oasis in the desert of gneiss, and independently of this merit, it possesses that interest arising from obscurity which never fails to rouse the attention. The aspect of the surface of this ridge and the cha- racter of its outline are so precisely similar to that of the island in general, that an observer, contented with a superficial view, would without hesitation note it as formed of the same rock. It offers a strong example of the necessity which the geologist is under of taking- nothing on trust, and of concluding nothing from in- duction when the evidence of contact can be obtained. The account of the ridge of Heval will be rendered more intelligible by disturbing the geographical order of this description ; and the reader will thus gain a key to solve difficulties which were to me a source of much research and trouble. It was shown that IVorth Uist is separated at its southern extremity from Benbecula by a complicated strait; improperly called Loch Rueval, since it has a free communication with the sea at both ends. This passage is strewed with a multitude of islands, Grimsa, one of the principal, having already been mentioned under the head of Benbecula, on account of its geographic re- semblance, as well as its physical identity. Many more, which I have thought it unnecessary to notice, such as Flodda, Bent, Broad Isle, and others whose names are scarcely known, belong like Grimsa to this division ; consisting of gneiss, and resembling their parent Ben- becula in every particular. But the hilly island Rona, together with its dependencies, Flota beg, Flota more, and others of minor note, are distinguished from these. 144 NORTH UIST. GEOLOGY. as much by their external aspect as by their structure, and ought to be ranked as portions of North Uist. There is also a chain of small islands lying ofF the mouth of Kyleswia, which, although more apparently connected with Benbecula, appertain in geological cha- racter to the islands in Rueval, now to be described. As I did not examine all the small islands scattered along this shore, some, which I have judged to belong to the gneiss of Benbecula, may perhaps prove, like Rona, to be parts of the rock of Heval : but these omissions are of no importance. Close to the two Flotas is a small island, not named in maps, which is here selected on account of its simplicity, as a foundation for the description of these obscure rocks. It consists of an argillaceous schistus of a pale grey colour, placed in beds nearly horizontal or with a small elevation, and apparently with very little disturbance. Some of the small rocks and islands in the neighbourhood exhibit a similar construction with slight variations. The schist is sometimes of a dark lead blue, of a more compact texture, and less regular in position ; and in many places it contains green compact felspar diffused through it in threads and laminae. In some other places it assumes a diversity of character; and among these, Flota beg and Flota more offer the largest surfaces for examination. The schist is in these islands occasionally traversed by granite veins, similar in aspect and composition to those which traverse the gneiss of the neighbouring parts, This may be adduced as a proof of the posteriority of these veins to the rocks which they intersect; since they -are here, as in Coll, found to pass indis- criminately through two different rocks, of which the one appears from its position to be of more recent formation than the other. It was already remarked in describing lona, that where the argillaceous schist approaches to the mass of granite it acquires a new 1 NORTH UrST. CxEOLOOr. 145 character, being interspersed with grains of felspar and quartz, or passing into a rock intermediate between granite and schist, or ultimately acquiring the external appearance of a gneiss of which the laminar tendency is produced by foliated portions of the schist. Some- thing similar occurs in the schist in this place. Where it approaches the granite veins it is much disturbed in its position, and the laminae become twisted and bent, or disappear altogether. Often, it is found to contain grains of granitic matter distinctly interspersed ; which accumulating in some places, there is at length seen a perfect transition from schist to granite. In examin- ing the contact of these distinct bodies, many varieties produced by this transition can be seen disposed in every mode of confusion. The surfaces which have been exposed to the action of the sea often show the marks of this mixture of character where it is not so easily detected by a fracture. They are every where thickly streAved with prominent points, the crystals of a harder matter which has resisted corrosion. This rough schist is mixed with the smooth, but in no evenness of order or regularity of alternation, the two kinds, as well as the accompanying granite veins, being every where confounded together in an irregular manner. There can be no hesitation in considering the rough schist as a portion of the smooth, altered by the con- tiguity or influence of the granite veins. The phe- nomena here are perfectly similar to those which occur both in the schist and limestone found in the vicinity of the granite in Glen Tilt ; of which I have given an account in the Transactions of the Geological Society. The same varieties of schist may also be observed at the foot of Heval, and on the shores of Rona. They constitute a rock distinct from gneiss, and will probably be considered as of more recent formation. It has indeed been said that clay slate, to which the schist in question belongs, is removed from gneiss as well as from granite VOL. I. L 146 NORTH UIST. — GEOLOGY. by the intervention of micaceous schist, and that it is the third rock in order from granite. It has been shown that in lona, clay slate is in contact with granite, and it will here be seen that it is in contact with gneiss, nay probably, in a state of alternation with that rock. If we follow the eastern shore of North XJist, we find the same argillaceous schist occupying the whole line, with trifling exceptions, wherever at least that shore is accessible ; and forming the lowest skirt of the range of hills here denominated the ridge of Heval. As may be expected, it varies considerably in different places, but after what has been already said in describing the small islands in Rueval, it is unnecessary to dwell on these variations. In many parts of this line, gneiss as well as schist is seen; the two rocks occurring in an irregular manner, and mixed in such a way as to give the greatest reason for supposing that they alternate. But if alternation can only be admitted where beds of one substance are found distinctly interchanged with those of another, it cannot be proved to exist here, on account of the extreme confusion which attends these rocks. Though the schist and gneiss occur alternately, neither of them is straight even for a small space, so that the relations which the one bears to the other cannot be determined. It is not in the least uncommon to find vertical beds in one place, and not an hundred yards from them others equally regular and absolutely ho- rizontal. The next rock that occurs^^ in Heval has an external form and aspect precisely similar to that of the gneiss which it accompanies, being rounded and difficult of decomposition, and causing the hills to appear as if paved with rocks, to the almost total exclusion of ve- getation. The beds, like those of the gneiss, are irre- gularly placed, occupying every possible direction, and being much contorted and dislocated. It alternates, NORTH UIST. GEOLOGY. 147 or is mixed in the irregular manner already described, both with the schist and with the gneiss by which it is accompanied. It is to be fomid in some of the low islands at the mouth of Kyleswiaveg, but is most conspicuous and most easily examined in the hills them- selves, appearing to terminate in gneiss on the shores of Loch' Maddy, as it ends in mere schist on the sea shore. It is difficult to render intelligible by description, the aspect of a rock or mixed mineral, but this will be most easily understood by referring the several va- rieties to those better known rocks which, in its simplest state, it most resembles. At one extreme it appears to be a lead coloured compact felspar, characterized by extreme toughness, and often by a twisted texture ; displaying at the same time a mixture of lighter and darker tints. When straight and even in the fracture, it resembles on a superficial view a siliceous schist. Occasionally it is interspersed with grains of transparent quartz, in which case small fragments would readily pass for specimens of hard felspar porphyiy. At times it is so penetrated by quartz diffused throughout in a sort of regular gradation, that the boundaries of the two are not visible. A new set of varieties is formed by similar admixtures of common felspar ; while other spe- cimens present mixtures of felspar and quartz, or felspar and hornblende, or hornblende and quartz, or of all the three substances united with the base. It passes in these cases into granite, or into hornblende schist ; or, by the ultimate exclusion of argillaceous schist, into gneiss. Portions also of common compact pale felspar are found in it, or beds in which this rock forms a basis slightly modified by the .occasional mixture of other ingredients. Such are the characters of the different portions of this rock, for which no name has yet been assigned, and of which I have no where else met with any resemblance. It may perhaps be considered as intermediate between gneiss and compact felspar; but 148 NORTH UIST. GEOLOGY. the venous distribution so generally to be traced in the latter substance rather seems to point it out as a gneiss altered by the subsequent intrusion of this mineral, and thus analogous to the rock described in Barra.* The gneiss found on the shores of Loch Maddy, occurs in all the variety of form and composition so often described, and may be traced throughout the greater part of the island. If there is any difference, it consists in the proportion of the straight being greater here to the contorted and displaced rock than in the pre- ceding islands. In some few places I observed beds so thin as to be capable of splitting into leaves not ill suited for heavy tiling, and, in others, it seems to pass, as in similar situations, into an unfoliated syenitic granite. The ramified basaltic veins formerly described as so abundant in Barra, are more rare in North Uist; but they also occur, being found in one or two places travers- ing the anomalous rock of Heval, and adding materially to the already complicated nature and obscure appearance of that rock. The other trap rocks that occur in this island have an unusual claim on a separate notice, as they present features of rather more importance than in those already described. The entrance to Loch Maddy, (the Lake of Dogs) is marked to mariners by two remarkable detached rocks situated about a quarter of a mile from the shore, named Maddy more and Maddy grisioch. The former is about 100 feet in height, and presents towards the land, a face irregularly columnar and inclined to the perpendicular in an angle of about 20°. The latter is much less distinctly marked by the tendency to vertical division, * I have since found a similar rock occupying a large tract on the north western coast of Ross-shire and passing into gneiss of the more ordinary characters. It may therefore be safely ranked an)ong the varieties of that rock. 1818. NORTH UrST. GEOLOGY. 149 is nearly of the same altitude, but appears about twice as large, its abrupt face looking equally towards the land, while, like the former, the opposed side shelves to the sea in an angle equal to the vertical deviation. Both these rocks are composed of a dark blueish grey and compact basalt, and they are remarkable as being the only rocks of this nature which occur on this coast, or in any part of the chain of the Long Island. There are many large veins of trap to be seen on various parts of the eastern shore of North Uist, but two of the most remarkable lie exactly opposite, one to each of, the rocks now described. The vein opposite to the Maddy more is easily seen in a lateral section, in consequence of the fall of the cliiT, and offers some interesting appearances. Viewed in front, its section appears parallel to the beds of clay slate which it tra- verses, but when seen from a lateral position it is found to cross them in a curved and somewhat waving course, terminating at the surface nearly at right angles to its original direction, and to the general bearing of the schistose strata. It is about twenty feet thick, and is divided by parallel lines into two or three beds ; of which one, about three feet in thickness, is amygdaloidal, con- taining nodules of mesotype and of analcime. The others have a tendency to split into irregular columnar forms. The phenomenon of stratified trap veins is not uncommon, but this and the accompanying instance are the most perfect examples of this structure that I have met with, since it is accompanied by marked differences in the several strata. This latter example, lying opposite to Maddy grisioch, is nearly straight, and has at first the appearance of a bed, but it is easy to perceive that it has no continuous conformity of position with the schist which it accompanies. In both cases the schist is much confused and distorted. What connexion may exist between the detached rocks and these veins, either here, or in Barra and the neighbour- 150 NORTH UIST. MINERALS. ing islands where they have already been described, does not appear. It is not absolutely necessary to imagine masses of trap in the vicinity of every vein ; yet it is not improbable, that, as these are always found predo- minant in the neighbourhood of such masses, the veins which occur throughout this part of the Long Island originate in masses of trap connected perhaps at some distant period with that of Sky, and of which Maddy more and Maddy grisioch are the only visible portions remaining. It would be superfluous to describe all the trap veins that occur along the east shore of North Uist. One however of a remarkable structure is to be seen in the little island of Hamersa in Loch Maddy. It is about fifteen or twenty feet in thickness, passing through the gneiss in a position nearly vertical. It is irregular, being split into minute ramifi- cations and thus very much confounded and mixed with the including rock, which is of an uncommon hardness. The weathered surface of this trap vein is studded with the same granite points as the schist of Flota More and Flota Beg. It possesses a degree of toughness scarcely inferior to that of cast iron. When broken it displays a number of minute red spots of a granitic aspect, but bears no resemblance to any of those well known greenstones in which red felspar forms an ingredient. In what respect this hardness and structure depend on the gneiss with which it is so intimately mixed, we can only conjecture. Among the mineral substances commonly found in gneiss, North Uist, like the neighbouring islands, abounds in reddish, grey, and white felspar, forming concretions in the granite veins often of very great magnitude. In some of the small islands situated in the entrance of Loch Maddy, it is found of a fawn colour. In one of these, Rilee, there is a considerable l)ed of opalescent quartz, very much resembling that which occurs in Coll, but more pure. This is occasionally tinged with a slight NORTH UIST. — MINERALS. 151 pink and with a blueish colour, but the greater part of it is milky. In many places the quartz which belongs to the gneiss is grey and semi-transparent : in others it is very dark, approaching to greyish black. In the same place crystals of hornblende of three or four inches in length are seen imbedded in quartz, and hornblende rock is also found in large concretions in the gneiss on the shores of some of these islands. These latter are often of a singular appearance, being formed of a congeries of crystals, loosely attached and, like coccolite, falling into grains by a very slight force. In certain situations garnets also occur in the gneiss beds. Of minerals unconnected with gneiss I observed none but a species of bog iron ore accompanied by pyrites. This is used by the natives in dyeing, with the assistance of tormentil, galium, lichens, and other native plants ; the uses and properties of which are familiar to the Highlanders every where, as they are to the Tartars who inhabit the plains of the Don. 152 KONA. GEOLOGY RONA* (WEST.) It has been already remarked that this island was a physical portion of the ridge of Heval, but it possesses some peculiarities worthy of attention. It is about 600 feet in height, presenting in its higher parts the same rocky aspect as Heval, and some low productive land being found skirting the shore. It is much indented, and exhibits to the east a broken face which seems, like the rest of the eastern shore already described, to consist of schist much disturbed and traversed by trap veins. The same irregidar mixture of gneiss, schist, and the anomalous rock described above, are found forming its upper parts ; both the mixture of the several rocks and the gradation from the schist to the gneiss being perhaps even more distinctly to be traced here than in the ridge of Heval, Where there are opportunities of observing this gradation, the change seems to be per- formed by a gradual increase of the granitic ingredient, the schistose parts communicating the laminar tendency. There is thus produced a rock with a perfect resemblance to gneiss, those portions which in more ordinary cases are formed of mica or hornblende, consisting of argillaceous schist. Reticulated trap veins are even more numerous here than in Heval, and they add much to the extraordinary appearance of this already obscure rock. Fawn coloured as well as dark quartz is found in the gneiss, together with felspar under the usual aspect which it possesses in these islands, being splendent and nacreous. Besides these, distinct beds of the same compact felspar d ex- scribed in lona occur in different places, some of * Ronti. Hon, a seal, Gaelic : Seal IsUiiul : a coiiinion apjK Ihition among the Western hies. RONA. GEOLOGY. 153 them being penetrated by basaltic veins so as to form a very singular compound rock. One of the beds of gneiss is remarkable on account of its beauty, con- sisting of a fine grained snow^y and equable mixture of quartz and felspar in which the several ingredients are scarcely distinguishable. The most conspicuous of the trap veins on this coast occurs at the southern end of Rona. It is nearly vertical, being thirty-six feet thick and traversing the schist in a N. N. W. direction. It is rendered interesting by the nests of tufaceous amygdaloid which are irregu- larly dispersed thoughout it and contain nodules of radiated mesotype. A great number of islands, some of considerable maonitude are found skirtino; the northern and western shores of North Uist, and dispersed throughout the sound of Harris.* They seem so unquestionably to be scattered portions of that island, or the fragments •of a common mass, that I thought it unnecessary to examine them allj and now think it useless to describe those which I did examine, since they afford room for no remarks in addition to those which have been repeated, perhaps unavoidably, too often already. Their general character may be understood by saying that they consist of rocky bases of greater or less elevation skirted by sandy shores. In general they possess the best pastures on this coast, being little encumbered with peat ; and as they are for the most part low, the quantity of naked rock is much less than is usually observed throughout this country. They are all very productive of sea-weed, from which great part of their revenues are derived. Wherever I examined the rocks I found them to consist of gneiss with no varieties worth recording. * For the names oftlicse the reader may consult the general Map. 1.54 HARRIS. GENERAL DESCRIPTION. HARRIS.* The northern half of the outer chain of islands is separated, as was lately shown, from the southern, by the sound of Harris, and is divided into two districts, the Lewis and the Harris, which however form but one island. This island, which appears to have no appro- priated name, is nearly intersected at the point called Tarbet by the indentations of the eastern and western seas ; a natural division which does not coincide with the political one, since that is denoted by an irregular line drawn from the middle of Loch Seaforth to the end of Loch Resort ; being the same which forms the line of demarcation between the two proprietors, Seaforth and Macleod of Harris. It will be most convenient to describe each division separately, although there is no point where the physical constitution of the two can be said to change. Harris is of an irregular form resembling the three quarters of a square, its diagonal length being about twenty-four miles, and its breadth about seven. It presents a coast every where deeply intersected by sea lochs, which, as is usually the case in this country, are interspersed with islands and rocks. On the east side, nearly the whole shore presents this character, few slopes descending into the sea, and scarcely a beach or sandy bay being visible throughout its whole extent. Numerous harbours are formed by these lochs ; while the intricacy of their sinuosities offer shores resembhng in length and complication those already described in Benbecula and North Uist ; with this difference however, that the * Pronounced Earradh by the Highlanders. This word signifies a division. Ear, a head, (Gaelic) may also be the origin (if the present name, which is a modernized one. HARRIS. — GENERAL DESCRIPTION. 155 islands and cliffs which form them are considerably higher, and often indeed approach to the mountain character. These rocks are bare, or sprinkled with rare and scanty patches of verdure, which, when of somewhat continuous extent, are generally inhabited by solitary tenants, sub- sisting by the double occupation of farming and of ma- nufacturing kelp. The intricate admixture of land and water, the occa- sional height and magnitude of the masses of rock, the unceasing variety of their forms and positions, and the magnificence of the screen of mountains by which this coast is backed, produce together a mass of picturesque scenery offering frequent and tempting subjects to the pencil of the artist. The scenes are often such as to remind him of the well-known and romantic recesses of Loch Ketterin,* and only require like them the orna- ment of trees to rank amongst the most picturesque parts of Scottish landscape. But art and Nature con- spiring have denied to Harris this necessary appendage of landscape as well as of rural economy, since not a shrub of higher claims than heath is to be found through- out the whole country. There is a period in civilization when wood is destroyed and there is a succeeding one when it is planted. But there is a long interregnum of severe want between these, and that interval is no more terminated in many parts of the main land of Scotland than it is in the shelterless plains and naked * The etymology, and consequently the spelling, of this name is so often mistaken that it may as well be rectified, Cath-earn, the th being dormant, men of war, or soldiers. Hence, following the orthogra- phy, Caterans, Ketterins ; the Quatrani of Fordun. Kernes, which follows the Gaelic pronunciation, is the well-known appellation of the Highland freebooters as used by Shakspeare, of which this lake from its vicinity to the Lowlands and the security of its trackless recesses, was a favourite strong hold. Hence the obvious impropriety of Loch Catherine. 156 HARRIS. GENERAL DESC RIP T10^^ mountains of the Long Island. The proprietors would fain believe that there are physical obstacles to its growth, and thus conceal from themselves those moral causes the contemplation of which is attended with self-accusation ; like those who in adversity argue themselves into a belief of fatalism to quiet the remonstrances of their own reflections. There are no physical obstacles, or none at least which Norway with a great similarity of feature, exposure, and rocky substratum, accompanied by a more severe climate, has not overcome.* Innumerable situa- tions adapted to the growth of trees are to be found in the sheltered valleys and on the lee sides of hills ; while the islands so plentifully scattered along the coast are calculated to remove the fundamental obstacle to planting, Tiamely, the expense of enclosure. One of the main diffi- culties to be surmounted, is, in fact, the want of capital to expend on improvements from which the returns are not immediate, and the wants, real or imaginary, of the landed proprietors, who are too often intent on procuring from the soil the utmost immediate rent which it can be made to afford. To these causes I may add the non-residence of the proprietors, who can not be expected to interest themselves in ornamenting those paternal seats from which they derive no pleasure. Even among those wlio actually reside, that indolence, so characteristic of the inferior classes of Highlanders and from which the superior •are not wholly exempt, is a perpetual bar to improvements of this nature. In a proportional degree, a Highland gen- tleman is as little anxious to multiply his enjoyments as his tenant, whose domestic animals dispute the fireside with * It is imagined that the oak will not grow to a large size but in a good soil. Among many remains of oak forests in Scotland, there are still remaining alive Tit the head of Loch Etive some trees from twenty to twenty-five feet in circumference growing out of granite rubbish. In ■such situations the growth is undoubtedly slow, V)ut the dmiensions do not seem to be so limited as has been often supposed. HARRIS. GENERAL DESCRIPTION. 1.67 himself, and vvhose smoke, for want of other vent, must find its exit at the door of his miserable hut.* On the southern side of Harris the hills are more clothed with earth and descend by more gentle slopes to the sea, in consequence of which an interrupted tract containing some good land is found along this coast. A road is formed in this direction, perhaps the only one practicable or even likely to be useful throughout the country. The west side, as far as Loch Tarbet, is marked by some accumulations of sand similar to those which abound in the islands already described, one con- siderable tract of which separates the hill called Toe Head so as to insulate it from the main island. West Loch Tarbet is a deep intersection between high mountains that rise on each side and descend by very steep decli- vities to the sea ; the land at its lower end being reduced to so narrow a neck as to admit of the carriage of boats from the west to the east side of the country. The whole circuit from this place to Loch Resort is of similar cha- racter, the mountains descending directly to the sea and generally terminating in a level shore indented by small bays and lochs. The boundary towards Lewis is merely an imaginary line holding an arbitrary course through an irregularly mountainous country. Such is the coast line. The interior of the country is one irregular group of mountains placed without order or connexion ; of very unequal elevation but generally * The following example is characteristic. An Highland estate was given in lease for 200 years to a cadet of the family, as a reward for military services, under the sole condition of delivering it at the expira- tion of the lease with a specified number of growing trees of a certain age, and under a determined fine for each tree deficient in the required age. That lease is on the point of expiring and as yet not a tree is planted. When I visited it not long ago the lessee informed me that he meant to plant to-morrow. He had been twenty years in possession, and his predecessors for five or six generations past had probably all like him intended for the last 200 years to plant " to-morrow." 4 158 HARRIS. SOIL AND SURFACE. high, and containing indeed some of the highest hills in Scotland. In this respect the character of Harris is entirely different from that of the islands immediately to the south of it. It probably does not any where contain twenty acres of level land in one spot. There is not at least a plain throughout the whole country, mountain following mountain in continual succession, uninterrupted even by that common feature in Scotland, the green glen or alluvial strath. The only land which at all approaches to an even surface, lies on the sandy shores of the western coast. The greater number of these mountains display surfaces of naked rock ; the same rock with the same general outline and aspect already described in the islands to the south. It is difficult indeed to form a conception of greater desolation and barrenness than is seen from the summit of any of the high mountains in this country ; entire surfaces of miles in extent appearing to consist of bare rock scarcely checquered by a spot of verdure, or even of that pretence to verdure, a mossy moor. Such is the case more particularly with Roneval, one of the highest mountains. In some places however, chiefly on the western and southern sides, there are declivities of tolerable pasture ; and similar patches are here and there scattered throughout the country wherever the declivity is such as to favour the accumula- tion of earth, and at the same time to repulse the lodg- ment of water and the consequent accumulation of peat. In similar situations, almost exclusively limited to the sea shore, is dispersed the population, in which this country like the greater part of the Highlands abounds, the small patches which admit of the plan of cultivation followed in most parts of the Highland maritime districts, being occupied by distinct families or held in joint tenantry, according to their several capacities. A few large pasture farms have been lately allotted, but the greater part of the land is held according to the plan till HARRIS. AGRICULTURE. 159 lately most prevalent in the Highlands, and formerly- mentioned by the name of run-rig. To a stranger, the mode of cultivation in use in these rocky districts presents a very singular aspect, in the sinuous ridges and minute patches occupied by corn or potatoes, which grow upon artificial beds heaped on the naked surfaces of the rock. By this almost Chinese system the shallow soils found on the rocky substratum are rendered productive ; the ac- cumulation of the beds increasing the earth to the neces- sary depth ; while the intervals between them, produced by the removal of the required portion, become the drains, which in a climate so moist and in soils of such a com- position, are the first steps towards cultivation. As far as this system is faulty, it is here only so on account of that w^aste and misdirection of industry already noticed in the remarks which have preceded : if it is right that such land should be cultivated, no better plan could be devised. But it is extended also to cases where it is by no means the best system that might be adopted, and where, on the contrary, the same quantity of industry bestowed in a different manner would produce more effectual and more permanent improvements. I allude to the very common practice of constructing similar beds on peat mosses where there is a great depth of soil. By this practice a certain extent, of surface is brought into cultivation by a method of drainage which is laborious while it is neither permanent nor extensive ; it being obvious that the same quantity of spade-work applied to the construction of well-directed and deep drains, would unwater the whole space, w^hereas, in this practice, no portion is drained but that heap which has with much toil been thrown up on the surface. In Harris, as throughout these islands, the best soil and consequently the greenest pastures, are found on the sea-shores. In consequence of the vicinity of the sea being unfavourable to the formation of peat, the soil in these places, instead of being encumbered, as in the interior, \60 TIARTIIS. ALLUVIA. with an inert mass of this substance, is clolhed with the Fes-r tucce, Aira^, and other grasses wliich usually affect similar situations. I have shown that in the southern islands this often depends on the admixture of sand, but it is also to be seen here as well as in Lewis, in situations where no sand is found. While on this subject I may remark, that there appear to be much greater accumulations of clay in Harris than even in North Uist, producing in many places an excellent soil capable of an almost constant system of culture. This accumulation is very remarkable even on the summits of the hills, where it often forms beds of a foot or more in thickness, which, when unencumbered with peat, produce excellent grasses, unless where ele- vated into too high a region. This earth, like that of North Uist, is extremely fine and soft, resembling porce- lain earth when free from the black colour it sometimes acquires from the peat, and evidently derived from the decomposition of the felspar which abounds in the gneiss. In many places it is so mixed with the decomposed peat as to form a perfect black mould. I observed but few alluvial accumulations of greater note than this ; no banks or beds of mixed stony and earthy mat- ter, nor any of those deposits which mark the effects, either of distant revolutions of the surface, or of the more recent action of water. The want of recent accumulations may be accounted for, as in the adjoining islands, partly by the want of rivers and torrents, aod partly by the extremely durable and refractory nature of the rock. In this respect Harris, as a mountainous country, presents a character somewhat remarkable in Scotland. The deficiency of running water is not the consequence of a want of rain, since the climate is considerably more rainy than that of any part of the Long Island, the mountains being frequently involved in clouds for many days, when the country both to the north and south is enjoying a serene atmosphere. It appears to depend partly on the mode in which the mountains are grouped, and parlly on the HARRIS. MOUNTAINS. l6l want of those fissures in the rock which are necessary for the production of springs. Hence every shower is speedily conveyed over the surface to the nearest hollow, where it almost immediately finds a passage into the sea, scarcely any number of small streams uniting into a larger river. Those at Rowdill and at Loch Resort appear to be the most considerable. Occasional torrents carry but little waste with them ; often indeed there are scarcely any fragments to be found on the faces of the hills, or they are thinly scattered over the firm rocky surface. In this respect the hills of Harris, as well as those of the Long Island in general, present a marked dissimilarity to those of quartz rock, of granite, of syenite, or of porphyry, that are found in various parts of Scotland, the waste of which is rapid and constant. That character which is so striking in the greater part of the Long Island, the abund- ance of fresh-water lakes, is equally wanting in Harris. As there are no plains, there are consequently no places where such waters can accumulate ; and the few moun- tain pools that occur are no more frequent than in other mountainous parts of Scotland. It need scarcely now be observed, that a country such as is here described, where unsurmountable rocks and impassable bogs alternately claim the mastery, cannot be traversed with much ease. There are indeed many parts which have probably never been trodden even by the shepherd's foot. I nevertheless succeeded in ascending such mountains in different places as to be enabled to give an estimate of their altitudes suf- ficiently accurate for all common purposes of topo- graphical description. Such measurements do not appear of any great value in a geological view, as the successions and relative positions of rocks are totally unconnected with altitude of place. Every observer will find daily reason to reject the doctrine of the relative levels of the exposed edges, or outgoings, as they have been VOL. I. M 162 HARRIS. — MOUNTAINS. called, of the several classes of rock. This is an example, among numerous others, of premature induction in the science of geology, and deserves not to have its ex- istence prolonged by a formal discussion. The altitude of the mountain Lang, one of the highest of the group which bounds the north side of west Loch Tarbet, was 2407 feet, as taken by the barometer. A storm and the coming on of night together, prevented me from traversing the precipices to be surmounted between this and the next highest summit, that of Chsseval. By various modes of estimating it both near at hand and at a distance, from different points, it appeared to be at least 300 feet higher : it may even be more. This is very obviously the highest hill in Harris, or indeed in the whole chain of the Long Isle, its pre-eminence being every where distinctly visible. From this, as the centre of the highest group, various other hills, the names of which I could not discover,* descend by gradual stages to Loch Resort on the one hand, and to Loch Seaforth on the other ; two or three of the neighbouring summits attaining nearly the same height as that of Lang. The hill of Roneval, which lies above Rowdill, is the next in elevation. The violence of the wind pre- * It is not intended as an excuse for neglect, to say that such local in- formation cannot often be obtained. He that is contented with a first an- swer in the Highlands will indeed never be at a loss for at least the appearance of information. Unfortunately it will seldom bear a scrutiny, a second question generally rendering void the effect of the first. " How long is this Loch.?'' — "It will be about twanty mile." — "Twenty miles! surely it cannot be so much." — "Maybe it will be twelve." — " It does not seem more than four." — " Indeed I'm thinking ye're right." — " Really you seem to know nothing about the matter" — " Troth I canna say I do." This trait of character is universal, and the answer is always so decided, that the inquirer, unless he is a strenuous doubter, is not induced to verify the statement by this mode of cross-examination. HARRIS. GEOLOGY. 163 vented me from finding the true level of the barometer,* but it appeared to lie between two points which would give the limits of height each way as 2200 and 2500 feet. This mountain forms one prolonged ridge, and is somewhat insulated ; from which cause it is the most conspicuous feature on the east side of the country. The remainder of the southern division as far as Tarbet, is of much less elevation than the group already described as forming the northern half; and may be conceived to vary from 2000 to 1000 feet, dechning from the centre of the country on each hand, both towards the eastern and the western shores. Such is the general disposition of Harris. Its geo- logical history is comprised in a narrow compass, as the reader must be prepared to expect, since it was already said to be a country of gneiss. I have had occasion to describe so often the chief characters of this rock, that I shall here only notice those pecu- liarities which occur in this tract of country, and those mineral substances or rocks which are associated with it. It is probable that something is still left undiscovered, amidst its almost inaccessible deserts, to reward the toils of future geologists. A remarkable variety occurs at Curihunish point. This consists of a nearly equal granular mixture of argillaceous schist with felspar and a little quartz, having the aspect of a grey granite, since the laminar tendency is barely dis- coverable. It is disposed in immense squared masses very much resembling the granites of Arran and Dartmoor, and in forms so regular and rectangular as scarcely to * Every mountain barometer should be provided with a screw for securing it fii-mly in the gimbals in the perpendicular position. Without such a contrivance the instrument is nearly useless in windy weather. 164 HARRIS. — GEOLOGY. require the aid of the tool to render them fit for masonry. They are all so loose as to be readily moved by the lever, and would form an admirable quarry for archi- tectural purposes where lai-ge masses were wanted, should any demand for such works occur in a situation where they could be conveniently obtained. In Roneval* also the gneiss, as in many places already described, loses, in part or entirely, the laminar character, becoming thus scarcely distinguishable from granite. Hornblende is here abundant, and in the same specimens are numerous large garnets often possessing an imperfect degree of transparency. In some instances the garnet is not se- parately crystallized, but so equally diffused through the rock as to give the whole a dark crimson blush. Among the veins of granite are found beautiful examples of the graphic variety, of which the felspar is white, translu- cent, and nacreous, acquiring after exposure an argen- tine brilliancy. Trap veins, or indications of them, occur in Harris, but they are not abundant. The most remarkable which I observed is on the top of Roneval, being 20 feet wide, vertical, and lying in a north westerly direction. At the foot of Roneval a low irregular ridge of limestone is found extending in an interrupted manner for a mile or more towards Loch Rowdill. A church of ancient and tolerable architecture, formerly the church of the monastery of Rowdill, and one of the very few buildings which time and the Scottish reformation have spared, will guide the mineralogist to the spot where it is most easily observed. f It hes among the gneiss, * The level surface of this mountain presents a singular instance of the force of the wind ; the fragments tliat cover it, often of con- siderable size, being disposed in prolonged ridges divided by distinct furrows in the direction of the prevalent western gales ; the beginning of each ridge being determined by the shelter of some fixed rock. t The church of Rowdill presents some peculiarities in sculpture well worth the notice of an antiquary, and from their analogy to HARUIS. i^IINEllALS. 1 65 and is often accompanied by a sort of micaceous schist, the position being irregular, but generally vertical. It is of a character very strongly resembling one of the varieties found in Tirey ; being of a pale or dark grey colour speckled with darker spots of the same, and sometimes even verging to a blue ; more rarely greenish, and containing specks or large pieces of transparent serpen- tine. At times it contains grey and watery sahlite or dark green coccolite, either dispersed in grains or inti- mately blended with the general mass, or lastly aggre- gated into lumps : it also contains mica disposed in a similar manner. Hornblende also occurs in it as in that of Tirey, in large concretions, but is more rare than the sahlite. On the shore at Rowdill, and in various other places, green compact felspar is found, forming an integrant portion of the gneiss, and often in veiy large masses. This substance is very prevalent throughout these islands, as it is in Tirey, Coll, and Zona. But among the simple minerals to be seen in Harris, felspar, as might be expected, is the most conspicuous. It forms distinct concretions in the gneiss, often of very large dimensions, and appears under a great variety of aspects. It occurs in very large masses of a pearly lustre, and semi-transparent, accompanying the graphic granite before mentioned, and forming specimens of great beauty. From this it is found gradually tending to the more common foliated variety, and at length ap- proaching to the aspect of the compact kind, while its colour passes through various stages of ochre-yellow to a deep flesh colour. On that side of Roneval which faces Rowdill there is a vein of quartz of a rare variety and of great beauty. It is chiefly granular, emulating the certain allusions in oriental worship, objects of much curiosity. They are hence unfit for notice in a work of this nature. Any remarks would moreover be superfluous, as they will probably in no loug time receive illustration from a pen to which the public has lately been indebted for a great part of its amusement. 165 HARRIS. MINERALS. finest sugar as well in the splendour of its colour as the minuteness of its texture, but passes by degrees into the compact form. Sahlite is the most interesting mineral found in Harris, where it is scarcely less various in aspect or less abundant than in Tirey. It has already been observed that it occurs here in the limestone, as it also does in Glen Elg, in Glen Tilt, and in Tirey ; either occupying distinct cavities, or else firmly imbedded in the rock. It is sometimes crystallized in very flat- tened rhombic prisms with curved sides and summits ; the latter being dihedral, and the crystals of an inch in length. It is also found in irregular flattened hexaedral or octaedral prisms, most generally imbedded in the limestone. The colour is various, being either black, white, grey, greenish, or brown, two or more of these differently coloured concretions occasionally combining in the same mass. In texture it is sometimes opake, while in other cases it approaches to the vitreous aspect, exhibiting at the same time all the intermediate modi- fications. One variety is deserving of notice from its resemblance to a mineral to which the name of bronzite has been applied, and which, according to Hauy, belongs to the species diallage. This is of a clear umber brown, with somewhat of a metallic splendour, the structure being lamellar and approaching to the fibrous. In other respects it has the character of pyroxene, the angles of the in- tegrant prism measuring 88° and 92° nearly ; whereas those of diallage are almost equal, the more obtuse angle not much exceeding 90°. It is not unlikely that a further investigation of the several minerals classed under these different species may throw light on a subject at present somewhat obscure, and lead to the more ac- curate classification of some substances of which the affinities are as yet uncertain. The other form of the sahlite or pyroxene here occurring, is that of coccolite, or a congeries of independent and ill-determined minute HARRIS. — MINERALS. 167 crystals. These are sometimes distinctly imbedded in the limestone, as in Tirey, and of different colours, brown, black, greenish, and grey ; while in other cases they form separate masses adhering together in a granular distinct manner, and impressing each other like the grains of the pomegranate. The brown variety above mentioned is occasionally found in this manner, and being sometimes further intermingled with scales of mica, it forms a compound of a highly splendent and singular appearance. The last observation is almost too imperfect to be mentioned, excepting as it may point out a defect to be supplied by some other observer. It relates to asbestos found in the neighbourhood of Nishishee, on the western side of the country, and derived probably from some bed of serpentine which I did not discover. Chance must often combine with industry in finding those mi- nerals or beds of rock which occupy so small a space in a district of this difficult nature. 168 SCARPA, TARANSA. GEOLOGY. SCARPA, TARANSA, SCALPA. These three are the only detached islands of con- siderable size connected with Harris : in a geological view they may be considered as portions of it. The substances found in the two latter render them worthy of notice, although they present too little variety to call for a detailed consideration. Scarpa and Taransa are each mountainous, the former consisting of one rocky mountain of gneiss about 1000 feet in height, and the latter, of two hills of less eleva- tion connected by a sandy isthmus. I discovered nothing in Scarpa worthy of particular regard, but the granite veins of Taransa are conspicuous for the magnitude and beauty of the crystals of mica which they contain. The smaller are generally very regular, and are crystallized in short prisms or tables, often two inches in their long dimension : the larger are less regular, attaining to nearly a foot in length. They are rarely found so large in Scotland. Scalpa, or Glas island, situated on the eastern coast, is conspicuous for its light-house, being low, and, like all the rest of this shore, formed of irregular pro- tuberances of gneiss. To the geologist it is remark- able for a bed of serpentine, which the works required for the liofht-house have so far laid bare as to render it of very easy access throughout the whole of its con- nections. It traverses the promontory on which the light is erected, being, like the gneiss in which it lies, very irregular in disposition, but generally placed at a high angle, often indeed in a vertical position. At its boundary it in some places passes into a schistose rock, not easily distinguished at first sight from clay slate, and consisting of a smooth mixture of talcose schist with hornblende. In other places the boundary SCALPA. GEOLOGY. \69 between the gneiss and the proper sei^pentine, is a serpen- tine so full of hornblende in large crystals as to be dis- tinguishable with difficulty from a hornblende rock. Some of the varieties have a schistose aspect and fissile structure, their colours being likewise disposed in a laminar manner, so as to present a dark greenish basis, striped, and in some directions speckled with a paler tone of the same colour. These generally lie near the gneiss, the interior gradually assuming a more massive form, and displaying at length a fracture from which all appearance of foliated tendency has vanished. Talc slate is also occasionally found at the limit of the gneiss, mixed more or less with quartz of a very greasy aspect. In the interior of this bed, of which the thickest part may perhaps be estimated at 100 yards, a body of pot- stone is found, the harder serpentine passing into it by gentle degrees. The fine edge of its fracture is some- what translucent, like wax, and it is of a dark green colour. The serpentine contains, as is not uncommon, veins of dark green and of pure white steatite, sometimes fibrous, together with splendent veins of greenish asbestos. It offers no specimens of an ornamental nature. There are some peculiarities worthy of notice in the gneiss which accompanies it. In some parts this is almost a mere jnass of felspar with a splintery and granular frac- ture, and mottled with red and white ; the laminar dispo- sition being marked by these alternations of colour. Sometimes it is interlarainated with clay slate, and more rarely with talc, forming a talcaceous gneiss, a rock which I have only observed in this place and which serves to mark the connexion between the serpentine and its boundary. A more remarkable phenomenon is offered in the passage of the granite veins. They traverse the serpentine as well as the gneiss, in the former part of their course assuming a peculiar character, consisting of the usual mixture of quartz and felspar with talc superadded ; a proof that in this case at least the vein is influenced by the 170 SCALPA. GEOLOGY. substance through which it passes. Another variety of the gneiss occurring in this singular spot is also worthy of notice. It has the character of graywacke, consisting of an argillaceous base with imbedded grains of quartz and felspar. I have already shown on different occasions that micaceous schist as well as talcaceous and chlorite schist form beds in gneiss, and that even clay slate does the same : in this instance the rule may also be said to extend to graywacke. Trap veins are not wanting in this island, since a very large one of a laminar structure is found in a vertical position crossing the gneiss. Lastly, I may add to this account that small particles of chromat of iron are found dispersed in the serpentine.* * When in this island, a shoal of bottled-nosed whales amounting to some hundreds had been forced ashore and taken. They are very abundant in this sea in the autumnal season, following the herrings. They appear to pay that implicit obedience to a leader which is so remarkable among land animals, in the deer, and in the duck tribes. By this they are taken, since, when the head fish of the shoal has been driven on shore by the boats, the whole follow until they take the ground ; when their retreat is easily cut off. LEWIS. GENERAL DESCRIPTION. 17 LEWIS.* In the description of Harris I have said all that is neces- sary for distinguishing the boundary between the Lewis and that district ; the two, as I then remarked, forming but one island. The total length of Lewis is forty miles, from the boundary line to the Butt, and its greatest breadth, between R-u Ushenish and the Gallan Head, rather more than twenty. The outhne of the coast is much more regular than those of the preceding islands ; as it offers only one considerable indentation on the western side, and as the northern half scarcely possesses one of those inlets which, in the others, form such numerous and com- modious harbours. The same continuous disposition of the coast is also the reason why the shores of Lewis are so little encumbered with rocks : a circumstance which renders their navigation more easy, and comparatively free from risk. The coast-line is so different in character in different parts as to admit of no general description. From Loch Resort to the Gallan Head it consists of the declivities of a high group of mountains, terminating either in slopes and stony shores or in rugged and pre- cipitous cliffs. At the Gallan Head the great sinuosity containing Loch Bernera, Loch Roig, Loch Carlowa, and other subordinate indentations, commences. This intri- cate inland sea, the largest in the Long Isle, is sprinkled with numerous islands, many of which are of considerable magnitude, the largest, Great Bernera, being about six miles in length. The loch is thus hollowed into bays and interrupted by passages of such variety and intricacy, that it requires no ordinary degree of attention and of * This name, like many others, has been a stumbling block to Gaelic etymologists. It has been derived from Leod, Loda, the Scandinavian Divinity. It is commonly used with the article; The Lewis. 172 LEWIS. — GENERAL DESCRIPTION- readiness in discerning the true nature and bearings of land under such circumstances, to effect its circumnaviga- tion. With the chart it is sufficiently difficult; without that, it would be almost impracticable. The entrance of Loch Roig in particular is so obscure that a boat may pass within a few hundred yards of the entrance without perceiving it. * Intricate and entertaining as this naviga- tion is, it cannot be called picturesque ; as the land is in general low, with the exception of the southern mountains, which are seen at a distance towering above the Kyle Flota. The cliffs also which bound most of the islands and shores, are rugged, without beauty and with little elevation. Like all the cliffs of gneiss in these islands, they are broken into a number of minute and angular parts, which destroy that repose and breadth so necessary to the picturesque ; while the capricious and gaudy dis- tribution of colour which they derive from the inter- mixture of red and white granite with hornblende and common gneiss, interfere with tranquillity of tone as much as their fracture does with that of form. One or two detached rocks may perhaps be exempted from this general remark ; and of these, Gariveilan, placed at the mouth of the loch, is the most interesting ; displaying a detached arch of great height with considerable sim- plicity and grandeur of effect.f * It is amusing to observe the various grounds on which repu- tation is founded in different societies. The contempt with which tlie anxious, and often perilous, pursuit of " chucky-stanes " (pebbles), was viewed by the seamen, was suddenly converted into respect when the " Saxon" geologist was obliged to take the helm and bring back to the anchorage the boat which themselves could no longer guide. t A voyage through the narrow channels of these sea lochs is often attended by very picturesque circumstances and striking effects. On one occasion the water was like a mirror, but black as jet, from its depth and from the shallow of the high cliflfe which overhung it. The tide, Cowing with the rapidity of a torrent, glided past without a ri{>ple to indicate its movement, while the sail aloft wai filled by a LEWIS. — GENERAL DESCRIPTlOy. 173 A rocky shore with cUft's of unequal but moderate height and of similar character, interrupted by some sloping declivities, extends from here to Barvas ; whence to Ness a low shore is seen with a gentle and often alluvial slope, frequently terminating in a flat sandy beach. The rocky clifl's which form the northernmost extremity, commonly called the Butt of the Lewis, rise to the height of sixty or eighty feet, and ai'e continued with slight exceptions as far as Kneep Head, where they are suc- ceeded by low shores reaching, with the exception of the Aird, to Stornoway, the capital of this western land. At the Butt these cliffs are broken into rugged fonns of an aspect peculiarly savage, being at the same time hollowed into innumerable caves into which the western swell beats with almost incessant violence and noise. Arches and pillars detached by the power of tliis tm-bulent sea, form a series of objects from which a painter might select detached parts with great effect ; but the whole is unpleasing to a cultivated eye : there is too much of that which, sparinoly used, is conducive to the most powerful effects in painting as in poetry'. Near Stornoway a large tract of sand occurs on the shore, from which a peninsula called the Aird stretches towards the north-east, forming a low table laud bomided chiefly by rocky clifl's. Loch Stornoway ofters nothing remarkable but the excellence of its harbour, and from this to the Birken isles the coast resembles the rocky shores already described ; displaying one continuous and rugged face of gneiss. Loch Luerbost, like Loch Bernera, consists of a deep in- dentation sprinkled with islets, extending to ^nthin a few miles of Loch Keuhulavig, the eastern extremity of Loch Bernera, so as almost to intersect the land in this direction; as it also does towards the head of breeze that did not reach the surface. There was a death-like silence while the boat shot along undei- the dark rocks like an arrow : to a poetical imagination it might have appeared under a supernatural in- fluence: like the bark of Dante, angel-borne. 174 LEWIS. GENERAL DESCRIPTION. Loch Seaforth. Whatever claim the Birken isles may once have had to their name, they must long since have lost it, since neither birch nor any tree except a few stunted plants of Populus alba is to be seen through the whole extent of Lewis, Passing Loch Hourn the cliffs increase in height, the Kebock Head attaining an apparent elevation of 150 or 200 feet, but with a similarity of character to the preced- ing, while the interior land begins also to rise into that mountainous group which forms the southern part of this district. The mountain character, which had disappeared at Loch Bernera, now once more becomes predominant ; the land above the coast rising immediately into hills of considerable elevation which descend with rapid slopes and often inaccessible abruptness into the sea, while they often terminate on the shore by high and craggy cliffs. Loch Shell, Loch Valmnis, and Loch Brolum present, from this cause, inlets of considerable grandeur, resembling those which abound on the west side of the main land : but the most magnificent scenery of this coast is found at the entrance of Loch Clay, and in the bay which is the common opening of Loch Seaforth and Loch Trolamarig. The mountains here rise to a great height, and together with much grandeur of outline, form groups of highly picturesque composition. The course of Loch Clay is but short, while Loch Seaforth penetrates upwards of twelve miles inland, losing at length the mountain character which so strongly marks its opening to the sea. Here the coast line of Lewis terminates. The general aspect and face of the country is such as to admit of a very natural division into two portions, of characters quite distinct, although not divided by a strong line. The group of mountains which surrounds Clisseval continues across the common boundary of Lewis and Harris without change of character; branching away at length in a crescent-like form on the east and west sides, and maintaining in these directions a considerable altitude, LEWIS. GENERAL DESCRIPTION. 175 while in the centre it dechnes more rapidly into a set of lower elevations between the heads of Loch Rois: and Loch Seaforth. By degrees it subsides into an undulating and uneven land towards Loch Kenhulavig. The moun- tains on the west side, between Loch Resort and Loch Bernera, are however higher than those which lie from the entrance of Loch Seaforth to Loch Shell, and when viewed in different directions, whether from the sea, from the high lands in the interior, or from the highest summits of Hams, seem no way inferior to them in elevation. From these various positions, assuming points where the principal summits were at equal distances from the point of observation, I concluded that Suaneval was early equal in height to Clisseval in Harris, which, as already shown, was found to be 2,700 feet. As there is no map of this country * I found considerable difficulty in procuring the names of the mountains, and shall therefore mention no more of them ; observing merely that the other hills con- nected with this principal summit decline from it by very slow degrees till they terminate at the Gallan Head and the Kyles Flota. On the east side the altitudes are de- cidedly inferior, although these mountains also are in the first class. I can give no actual measurement of either range, as the disturbed state of the weather prevented me from ascending those few which are accessible. Few hills are to be observed in Lewis after the termination of this mountain district. A group of no great extent, and not reaching apparently to 800 feet in height, is seen on the north side of Loch Bemera. Shortly after this subsides, the hill of Barvas rises in the same direction to a similar elevation. This has a tame rounded outline and a mooiy surface interspersed with rocky patches, declining by an insensible gradation into the * That in Arrowsmith's work is, like many more of the Western islands, a mere outline, and a very incorrect one, apparently copied from the sea charts. 176 LEWIS. SOIL. general irregular level of the country. Still further north is seen the similarly rounded and low hill of Munach, owing its importance, like the former, to the almost level surface of the land by which it is surrounded. In the vicinity of the southern group both Munach and Barvas would be undistinguishable. With the exceptions now mentioned, the whole land of Lewis from the termina- tion of the southern group to the Butt, is low, partaking" of an irregular undulation in the vicinity of the hills, and subsiding into an uneven table land towards the northern extremity. The soil varies as the elevations change. While the summits and sides of the high hills are naked and rocky, the plain land is clothed with a thick bed of peat, obscur- ing almost every where the rocky substratum, or only suffering it to break through in occasional protuberances. The aspect of this interior level is that of an universal, desolate, brown moor; pastured in the summer months, and in the winter almost impassable to man or animals.* Towards the sea, as is generally the case, green pastures are found, and here also some tracts of alluvial land of considerable extent occur, affording an excellent soil. The best of this land lies at the northern extremity, and, wherever situated, it is the sole receptacle of the great population by which the Lewis like the rest of the Long Island is crowded, may I add, encumbered. * The deserted state of this tract is the result of its barren surface, but in general the present uninhabited parts of the Highlands have been unavoidably reduced to that condition by the system of sheep- farming. Thus many of them have been rendered nearly or altogether inaccessible to a traveller, from the want of houses where he may obtain shelter. It is not uncommon now to go thirty miles or more without seeing the trace of human existence. To the solitary wanderer, the deserted patch of green land in the mountains, or the abandoned valley with its ruined huts, presents an aspect peculiarly melancholy ; while he is often at a loss to explore his way, the tracks which for- merly conducted to those villages having been effaced by want of use. LEWIS. AGRICULTURE. 177 Although the surface of the interior country is every where a brown peat, it is in many places more susceptible of improvement than similar soils in the neighbouring islands. This superiority does not arise from climate, since there is no sensible difference between this country and the other parts of the chain ; if we except the very mountainous district of Harris, which is subject to an undue proportion of ram. The clay which lies above the rock is here more generally diffused and in greater abundance than in the southern islands ; while the thinner covering of peat on the undulating land renders access to it more practicable, so as to admit of its being turned up by the operations of agriculture. But the chief causes are, the form of the land and the frequent receptacles of water, which render it capable of being easily drained ; an improvement almost denied to the flat moory tracts of the southern islands. The progress of wealth may perhaps some day effect a change ; it may even be gradually carried into practice by the industry of the larger tenants and small crofters, if due encouragement be given to their exertions, and the preliminary of draining, (an operation from its expense impracticable by them,) is either adopted by the proprietor, or enforced under some regulation so directing the divided labours of the tenants as to make them tend to a general plan of drainage. It must nevertheless be remarked that this island has been for some time in a state of gradual improvement; while a stimulus is also given by the increasing wants of Stornoway and by the roads now forming in different pai-ts, from which a further extension of it may be ex- pected. It is to the want of capital that we must look for the abandoned state of many promising tracts of land throughout this country. Divided as that capital is, it must be applied in the present manner or cease to be applied at all. It cannot now be extended to a wider and more profitable range of objects, because it can VOL. I. N 178 lEWlS. — HISTORY OF TH£ WESTERN ISLE*. neither be accumulated under one comprehensive plan^ nor wait the slow returns which must ever follow the first advances in objects of this nature. Let the spec- tator who admires the industry of the small tenants, turn his eyes from the httle rocky croft of the laborious farmer, to the wide, undrained, unenclosed, and unpro- ductive moor, and there he will find Nature lano-uishino- for want of that attention w^hich bestowed on worse subjects supports the crowded population of this country. He will then perhaps exclaim against the want of in- dustry which suffers to lie waste, tracts of land capable of yielding great resources and of maintaining a great increase of the present population. But I need not dwell on this subject, the remarks made throughout various parts of this work being sufficient to convey a general idea of the political and agricultural state of these islands.* There are some circumstances in the population of Lewis connected with the ancient history of these islands, which are not to be observed elsewhere among them, nor perhaps any where so distinctly throughout the High- lands. A few remarks on these may not be unamusing to the reader, who can scarcely fail to have acquired some interest in the general history of the Western islands independent of that which arises from their physical structure. Numerous fishing boats are generally to be seen about the Butt, manned each by nine men rowing eight oars in • This district still possesses one of the ancient peculiarities now extinct in almost all the other islands, and indeed nearly so every where. This is the employment of tacksmen, of whom there are thirteen. It is unnecessary to discuss here the comparative advantages and defects of a system so nearly abandoned. The southern traveller will also be surprised to see women still employed in drawing the harrow, and in droves, like horses, carrying the peat from the moors into Stornnway. LEWIS. HISTORY OF THE WESTERN' ISLES. 179 double banks, a practice nowhere else to be observed. The people themselves are also strikingly dissimilar to the general population of the islands ; preserving their un- mixed Danish blood in as great purity at least as the inhabitants of Shetland ; and probably with much of the manners and appearance of the times when this country was an integrant part of the Norwegian kingdom. They constitute even now an independent colony among their neighbours, who still consider them as a distinct people, and almost view them in the light of foreigners. The district which they possess is by far the most fertile and valuable part of the island, and they occupy it in the ancient slovenly system of joint tenantry. They are reputed industrious fishermen, but they only fish for their own consumption; appearing to abound in food, as they are all fat and ruddy. They possess almost universally the blue eye and sanguine com- plexion of their original ancestors, and with their long matted hair never profaned by comb or scissars, can not be distinguished from the present race as we still meet them manning the northern ships. Notwithstanding their rude aspect and uncouth dress, they are mild in manners, and are esteemed acute and intelligent. It is perhaps a remarkable circumstance that they retain no peculiar traces of the northern tongue ; and indeed that throughout a country half peopled by the descendants of Norwegians, and where almost every local name is of northern origin, so few remains of the language should now be found. In this instance at least, the existing language offers no clue for tracing the revolutions of tribes, whatever hghts may be derived from topographic appellations. From whatever source these islands were originally peopled, and under whatever barbarous fonn of govern- ment their scanty population existed during the period in which the Romans held Britain, it is known that they were svibjected to the piratical incursions of the 180 LEWIS. — HISTORY OF THE WESTERN ISLES. Norwegian rovers during the eighth century. It is probable that in the time of these incursions, settlements were formed, and some of those names imposed which still continue to predominate among the islands. Little certain information can however be procured respecting these invasions till towards the end of the ninth century, the period of the conquests of Harold Harfagre, and the subsequent revolt of Ketil; under whose sway a Norwegian government was consolidated in the Western islands. The new kingdom of Man, which immediately succeeded, absorbed within itself the whole of them ; yet some obscurity hangs over the nature and extent of this sovereignty, as it appears, that although during the whole of this period they were subject to the kingdom of Norway, and were under the immediate command of lieutenants sent from that country, they payed tribute to the Earls of Caithness and Orkney. Antiquaries have vainly endeavoured to throw light on the obscurity of these times ; but in truth the elucidation of the exploits of these roving freebooters, unless it may be supposed to derive some merit from its difficulty, seems as little interesting as the history of those who now roam through the islands of the Pacific ocean, bran- dishing the wooden spear and the war club. A gleam of light appears on the arrival of Magnus the bare-footed, who being called to the assistance of Donaldbane about the end of the eleventh century, conquered and laid waste the islands, consolidating his dominion over them and adding to it the peninsula of Cantyre. Between this period and the time of the battle of Largs, fatal to the Norwegian power in Scotland, they seem to have remained under the dominion of Nor- way, nominal at least if not real; since on several occasions it appears that its lieutenants or viceroys assumed the kingly title, and either renounced their allegiance altogether, or sought protection from England or from Scotland, as the politics of those days, not LEWIS. HISTORY OF THE WESTERN ISLES. 181 less intricate, if less important, than those of our own, might vary. The battle of Largs, fought in 1263, ter- minated in the cession of all the Norwegian possessions in Scotland to Alexander the Third, who thus acquired by treaty that which his predecessors had hitherto been unable to conquer or retain. It is perhaps to a subsequent period that we must look for the introduction of the present language and the disappearance of the Scandinavian, if indeed it be at all capable of proof that the language of the aboriginal settlers was not the same Celtic as that spoken by the Irish and the Highlanders ; the present Gaelic dialect. If this should be admitted, the difficulty of accounting for the loss of the Scandinavian is removed ; since it. is easy to imagine that the temporary and partial set- tlement of the country by the Norwegians had failed to produce a permanent or marked change in the language ; and that the descendants of these conquerors, being the minor portion of the population, conformed in course of time, as the Normans did in England, to the pre- vailing tongue. The existence of local names of northern origin is compatible with this supposition. But I am aware that this is delicate ground, and that formidable antiquaries who imagine that they have traced the migra- tions of the Scoto-Irish and the more recent establish- ment of their dialect, to later periods, are in array against this supposition. The history of the islands which follows the period of their cession to Scotland is better known and more popular ; since it contains the rise of the great chieftains who so often resisted the authority and troubled the repose of the Scottish monarchy, and whose descendants are still the heads of clans not long deprived of their independence. The Macdougal and the Macdonald were the original chieftains who, by immediate descent from the Thane of Argyll and the King of Man, divided the whole of the isles between them, the northern 182 LEWIS. HISTORY OF THE WESTERN ISLES. becoming the kingdom of the Macdougals, and the southern that of the Macdonalds. For nearly a century, the history of these barbarous chieftains and their descendants is unknown, although there is sufficient evidence of their independence of the Scottish crown, at that time feeble and fully employed in maintaining itself both in foreign wars and against the encroachments of its own subjects. The year 1335 is marked by the open defection of John, Lord of the Isles, who with some of his immediate ancestors is also known by the title of Earl of Ross. The independence of this petty prince is proved by the record of a treaty formed with Henry the Fourth, and by the subsequent unsuccessful invasion of the north of Scotland by Donald his brother. During the remainder of the reign of James the First, and that of James the Second, inroads of the same predatory and barbarous nature were frequently renewed, and with various success; being always attended with atrocities of the most cruel description. On a subsequent occasion we again find the Court of England in treaty with the Lord of the Isles for his assistance in the conquest of Scotland, but this alliance was annulled by the change which took place in the policy of Edvv'ard the Fourth with regard to James the Third, the reigning Scottish monarch. James, thus at leisure, directed his attention to the conquest of this troublesome and rebellious subject ; and in consequence of the submission of the Earl of Ross, he was reinvested with the lordship of the isles, but on condition of feudal acknowledgment and service. The period which follows this, presents a continued re- newal of insurrection and rebellion, or of quarrels and battles among the petty chiefs, who appear to have acquired at this time a sort of separate independence, the origin, or the counterpart at least, of those family feuds that occupied the Highlands in general to a late period. These produced a state of perpetual war between various Jj.ttle kings; each of whom, supreme in his own territory, LEWIS. HISTORY OF THE WESTERN ISLES. 183 scarcely acknowledged the power of the sovereign who ruled the kingdom. The voyage of James the Fifth through the islands produced a temporary tranquillity ; and the examples then made of several chieftains, whose names are on record, prove that the number of these independent sovereigns had considerably multiplied since the grant made by James the Third to the Lord of the Isles. That tranquillity soon ceased. After the death of James, fresh rebellions and a renewed state of anarchy arose, while the piracies and depredations of these ferocious people rendered them the terror both of Ireland and of the neighbouring coasts of Scotland. During these troubles the power of the Campbells, employed by the policy of the times against the chieftains, rose on their ruin, and among other deprivations, Isla was taken from the Macdonalds and granted by James the Sixth to Sir John Campbell of Calder. The history of the commonwealth, and that of the reign of William III., still however show, that the same turbulence and the same notion of independence con- tinued to prevail among the clans ; but it is unnecessary to protract their history to a later date, as the ter- mination of their independence and their reduction under the legitimate power of government have passed almost in our own times. Such was the system that produced the feuds, the battles, and the massacres, of which every bay and every cave still furnish some tradition. Yet there are those who can look back with complacence to a history abounding with the most outrageous acts of cruelty ; to a system compounded of tyranny and slavery, to perpetual war and famine and desolation ; to the absence of all the arts, the habits, and the feelings of civilized life ; the contempt of laws, and the most profound ignorance of all which distinguishes an European from a Cherokee. A change of terms is often the test of truth ; and, in recollecting the realities of Indian 184 LEWIS.-— ANTIQUITIES, warfare, the pleasing dreams in which we are apt to con- template the feudal Highland government, evaporate. The dearth as well as the unimportant nature of the antiquities found in the Western islands is such, that it is rarely necessary to allot much space to their de- scription. The greater number of those which occur in Lewis resemble so nearly those described in other parts of this work, and are at the same time so little interesting, as to require no detailed notice. Its Druidical monu- ments are however numerous and remarkable, althoug-h hitherto recorded only in the imperfect accounts of Martin and in the equally unsatisfactory reports of the Statistical Survey. It is well known that Scotland possesses numerous specimens of those structures which have been attributed to the Druids, but, with the present exception, they are, in the Western islands, both rare and unimportant. The neighbourhood of Loch Bernera contains many of them, and all comprised in a tract comparatively small, since a square mile would probably include the whole. They are situated in an open and fertile tract on the borders of this intricate inlet of the sea ; and if they were really temples dedicated to Druidical worship, their aggregation would seem to imply that this spot was the seat of a college, as it has been called, of this order of priests ; a Druidical monastery. Even in this case, the number crowded into one spot, in a country of which the population in ancient times must have been thinly disseminated, may be allowed to excite reasonable doubts respecting their real destination. But it is fruitless to speculate on subjects which seem doomed for ever to doubt and conjecture. I will however describe the most remarkable of these erections, since the magnitude and disposition of the work bespeak its former importance, and since its state of integrity renders it, after Stonehenge, among LEWIS. ANTIQUITIES. 185 the most interesting which have been found in Britain. I have added an etching for the purpose of showing the general disposition more perfectly than words are capable of explaining it.* The form is that of a cross, containing at the inter- section a circle vvdth a central stone ; an additional line being superadded on one side of the longest arms and nearly parallel to it. Were this line absent, its form and proportion would be nearly that of the Roman cross or common crucifix. The longest line of this cross, which may be considered as the general bearing of the work, lies in a direction 24° west of the meridian. The total length of this line is at present 588 feet, but there are stones to be found in the same direction for upwards of 90 feet further, which have apparently been a continuation of it, but which having fallen, like others through different parts of the building, have sometimes been overwhelmed with vegetation, leaving blanks that impair its present con- tinuity. The whole length may therefore with little hesitation be taken at 700 feet. The cross line, inter- secting that now described at right angles, measures 204 feet, but as it is longer on one side than the other, its true measure is probably also greater, although I was not able to discover any fallen stones at the extremities ; the progress of cultivation having here in- terfered with the integrity of the work. The diameter of the circle which occupies the centre of the cross is sixty-three feet, the lines ceasing where they meet the circumference. The stone which marks the centre is twelve feet in height. The heights of the other stones which are used in the construction are various, but they rarely reach beyond four feet : a few of seven or eight feet are to be found, and one reaching to thirteen is seen near the extremity of the long line. * Plate XXX, fig. 1. ■ 185 LEWIS. ANTIQUITIES. The additional line already mentioned, extends north- wards from the outer part of the circle, on the eastern side. It is however very defective, a great number of the stones being absent towards its northern extremity; although there is apparent evidence of their former con- tinuity, in one which remains erect and in others which have fallen from their places. I could not discover any traces of a line parallel to this on the western side ; but as some inclosures have been made in the immediate vicinity, it is possible that such might have originally existed ; notwithstanding the superstitious reverence 'with which the Scots in general regard these remains, and the care with which, in their agricultural operations, they commonly avoid committing any injury to them. The intervals between the stones vary from two to ten feet or more, but it is probable that the larger spaces have resulted from the falling of the less firmly rooted pillars which occupied those places. The number of stones in the circle is thirteen, independently of the central one ; and the number in the whole building, either erect or recently fallen, is forty-seven. The aspect of this work is very striking, as it occupies the highest situation on a gentle swelling eminence of moor land ; there being no object, not even a rock or stone, to divert the attention and diminish the impres- sion which it makes. The circles found in the vicinity are less perfect, and present no linear appendages : their average diameter varies from forty to fifty feet, and one of them contains four uprights placed in a quadrangular form within its area. I may add to this general account, that solitary stones, apparently of a monumental nature, are found in this neighbourhood, as well as in the island of Bernera and in other parts of Lewis. The cruciform shape of the structure described above is a remarkable, and I believe a solitary circumstance. It has not at least been noticed among the numerous descriptions of these erections which antiquaries have LEM'IS. — ANTIQUITIES. 187 given to the public. It i.s true, that in some of" the cromlechs or smaller monuments, a disposition of the stones resembling that of a cross has sometimes been remarked, but it seems in all these cases to have been the result either of accident or necessity. No monu- ments in which that form is obviously intended, have been traced higher than the period of the introduction of Christianity ; nor was it indeed till a later age, that of Constantine, that the cross became a general object of veneration. From that time its use is common ; and it is frequently found applied under a great variety of structures and forms, to numerous objects, civil and military, as well as ecclesiastical. Those cases in which the figure of the cross has been found marked or carved on stones of higher antiquity, which had served either for the purposes of sepulchral memorials or Druidical worship, appear to have resulted from the attempts of the early catholics to convert the supposed monuments of ancient superstition to their own ends ; either from economical motives or from feelings of a religious nature. But such attempts cannot be supposed to have given rise to the peculiar figure of the structure here described. The whole is too consistent and too much of one age to admit of such a supposition ; while, at the same time, it could not under any circumstances have been appli- cable to a Christian worship. Its essential part, the circular area, and the number of similar structures found in the vicinity, equally bespeak its ancient origin. It must therefore be concluded that the cruciform shape was given by the original contrivers of the fabric, and it will afford an object of speculation to antiquaries, who, if they are sometimes accused of heaping additional obscurity on the records of antiquity, must also be allowed the frequent merit of ehciting light from dark- ness. To them I wiUingly consign all further speculations concerning it. The remains of one of those singular structures called 188 LEWIS. ANTIQUITIES. Pictlsh Towers, is found not far from this place, con- nected with a subterranean passage which is supposed by the natives to reach the sea. To trace the date, or the authors, of these buildings, appears a hopeless attempt, as no analogous works appear to exist else- where,' and neither carvings, monuments, nor inscriptions, have been found attached to them so as to give a pro- bable clue towards the discovery. It is unnecessary here to notice the impropriety of the appellation, but it is not unimportant to remark that they are all limited to the northern division of Scotland. From that situation, it is probable that they were the works of the Northmen, whose colonies possessed those tracts ; an opinion con- firmed by the northern name Dornadilla, the only local title among them, as far as I have discovered, now exist- ing. The most southern are those in Glen Elg and on the frith of Tain. They are numerous in Sutherland ; although, with the exception of Dun Dornadil, these are now all nearly levelled to the ground. In Glen Elg they are sufficiently entire to convey a perfect idea of their structure, for which I may refer to Pennant, in whose work they are accurately represented. The three in Glen Elg are of the same size or nearly so. Those in Sutherland vary, and in some instances appear to have been of somewhat smaller dimensions, as far as can be judged from their present dilapidated state. It is very difficult to comprehend the design of the archi- tects, since the upper galleries, that lie between the inner and outer wall, are insufficient to admit a man : in some, a child could scarcely creep along. Nor are these galleries provided with external apertures for defence, a circumstance which bespeaks the purpose of that con- struction in the Galloway towers, and in those keeps, which, like that of Restormel Castle, consist of two concentric walls with an interior space. It is probable that they were merely the strong houses of the chieftains of those daysy the internal area being perhaps appropriated to the LEWIS. ALLUVIA. 189 occasional inclosure of the cattle in cases of alarm or warfare. Of their relative antiquity to those much more singular buildings, the vitrified works, it is impossible to conjecture. Fresh water lakes are found among the hollows of the hills, and are scattered over the mooiy surface of the level land, but they do not form the same characteristic and distinguishing feature as in North and South Uist, and in Benbecula. Compared with the rest of the Long- Island, Lewis may be said to possess rivers. These are at least tolerably permanent, but in any other situation they would attract little notice. The largest are at Loch Stornowi^y, Loch Kenhulavig, and Loch Roig, the last of which is somewhat distinguished by a salmon fisheiy. The courses of these streams are attended by no alluvia or other appearances deserving of notice in a geological view. The alluvial land which is to be seen in Lewis is inde- pendent of these, and however common a feature, is in this situation remarkable, since it occurs no where else in the whole chain of the Long Isle, with the slight exception already mentioned in North Uist. It appears to owe its origin to distant changes on which we have no other conjectures to offer than such as have been often produced to account for similar alluvia in various parts of the globe. In one respect it presents a diffi- culty, arising from the insular position of the land which it occupies ; but even that difficulty is far from solitary, since similar alluvia have been observed in insular situations, and examples of them are described in other parts of this work. If, here as elsewhere, it is fruitless to inquire into the causes of these accumu- lations, it is no less difficult to conjecture what the circumstances were which limited the deposits to the northern extremity of this long chain. This alluvial ]90 LEWIS. GKOLOGY. matter consists of clay and of clay-maile, together with a mixture of rolled stones of different kinds, but always, I believe, of quartz, felspar, and the several varieties of gneiss. Thus they seem at least to derive their origin from the waste of mountains of gneiss. But they do not lie in the vicinity of the mountainous district, being, on the contrary, visible only towards the north end of the island, where their broken and mouldering edges may be traced and measured on the shores. At Ness, Dale, and Leanol, they are from fifty to seventy feet or upwards in thickness ; and repose, where their contact can be observed, immediately on the gneiss which forms the substratum of almost the whole country ; the rock immediately subjacent being generally in a rotten and mouldering state. With one or two exceptions, there is little to be re- marked respecting the rocks that constitute this island, which has not already come before the reader. Gneiss is the predominant and fundamental rock ; and I shall briefly notice such circumstances with regard to it as have not occurred on former occasions, or have occurred in a form less distinct. Every thing is worthy of attention which conduces to the due knowledge of any one rock ; since it is only by comparing the several forms, acci- dents, and connexions under which it is displayed, that a thorough knowledge ot' its natural history can be obtained ; a knowledge which, extended to all the objects in this tribe of substances, constitutes that science of which we are in search. The cliffs in various parts of the coast, at the Gallan Head, in the great Bernera, near Loch Carlowa, at the Butt and from it to Tolsta Head, and again from Stornoway to Loch Brolum, offer innumerable examples of the passage of granite veins and of the contortions of the gneiss. I have delineated a few, partly on account of their singularity, partly because they serve to show the changes which the rock must have undergone, and LEWIS. GEOLOGY. 191 because they illustrate practically that irregularity in the apparent position of the beds at the surface* which I have in the next article attempted to explain by a diagram founded on theoretical views.^- Among the very remarkable appearances displayed by the gneiss is the following, of which two examples occurred, one on Bernera isle, the other near Loch Kenhula\ag. In * PI. xii. fig. 6. f The first is selected to show a remarkable circumstance of frequent occurrence,t namely, the prolongation and compression of the beds; an appearance tending perhaps more strongly than any other of the numerous irregularities which it presents, to prove the soft and ductile state in which this rock has existed. It is to be observed on the island of Great Bernera. The next example is also to be seen in the same island, which offers innumerable contortions of the most fantastical nature ; and it almost equally with the former proves the once flexible state of this rock. The third is calculated to show that intricate position of the laminie, with those wavings and deviations, which produce, when only examined at the surface, the apparent irregularity in the position of beds of gneiss, a circumstance to which the diagram above mentioned refers. The present is from one of the shores of Loch Bernera. The fourth is at the Butt of the Lewis, the rock which contains it having the aspect of a piece of marbled paper and being above fifty feet in height. It is principally remarkable for the excess of the contortion. On these representations I must remark, that they are drawn as if on a plane surface, to render those bendings and lines which are perfectly visible in Nature equally so in the drawing. The hollows, asperities, and projecting fragments, do not prevent that from being quite distinct in the rock itself, which would be obscured in the drawing by the lines and shadows necessary to express these adventitious circumstances. The interlamlnatlon of the dark varieties which contain much horn- blende with those which contain little or none, are the lines by which the contortion is rendered visible in the rocks, and the sketches repre- sent the same by the alternations of black and white. The last of these flexures here delineated is to be seen in the cliffs near Loch Hourn on the eastern side, although similar examples occur in various places. Imagination indeed can scarcely conceive an intricacy of this nature of which a resemblance could not be found in Lewis, which far surpasses all the other islands already described in the variety and distinctness of these phenomena. PI. xii. fig. 1, 2, 3, 4, 5. 192 LEWIS. GEOLOGY. both these a sudden and complete change in the direc- tion of the laminae takes place, the one set abutting against the other without any apparent intermedium. In one the position is at right angles, in the other oblique.* Such an union may be supposed to have taken place at the same period when the other dislocations and contortions were produced, the disjoined parts being capable of re- uniting while in a softened state. A fact somewhat similar, perhaps identical, is described by Saussureas having occurred to him on the glacier of Miage. He calls the rock a granitel of schorl and felspar, but offers no conjecture respecting it. Consider- ing the state of mineralogical nomenclature when he wrote, it is not improbable that his granitel was a gneiss resem- bling this. I have on different occasions described rocks occurring in the gneiss, of a character distinct from it, such as micaceous schist, talc schist, graywacke, and clay slate. At Loch Carlowa a similar circumstance is seen, the rock, which is of a very peculiar appearance, consisting of dark blue quartz interlaminated with black mica. A more remarkable example of the anomalous varieties of gneiss may be observed towards Oreby on different parts of the shore, where it forms an extensive range of rocks. It consists of an orange red felspar, with a harsh granular fracture proceeding apparently from an intermixture of quartz, containing distinct scales of an argillaceous schist mixed through it in a very regular manner and in a laminar direction. In the same place green compact felspar, similar to that of lona, is found in great abun- dance, forming distinct beds in the gneiss, or dispersed through it in thin plates and prolonged fibres. Not far from this place may be seen one of the most interesting varieties which occurred in the course of this investigation. It consists of the most usual intermixture * PI. xxxi. fig. 3. LEWIS. — GEOLOGY. 193 of dark and pale gneiss in pretty equal and parallel laminae, the darker parts abounding in hornblende, the lighter in felspar. Dispersed through this rock are crystalline concretions of felspar, thickly disseminated, and disposed in a laminar direction corresponding with the general structure of the rock. This felspar is splen- dent or nearly glassy, and the concretions, although highly crystalline within, have no external configuration. They are seldom less than a quarter of an inch in diameter, and attain to that of three inches. It is not unusual to meet with crystallized felspar in gneiss, and the appear- ances which it exhibits are often remarkable, as the laminee are generally bent and accommodated to the shape of the crystal. But it rarely in these cases exceeds the fourth of an inch, and seldom possesses that perfectly crystalline aspect which it here displays. This rock is also bent, like most others in the island, and is attended by an accidental circumstance which renders the incurvation particularly striking. This is the fallmg away of the surrounding parts, which have thus left standing an example, perhaps solitary, of a bent and detached rock. It is about thirty or forty feet high.* In the neighbourhood of Stornoway, and in the interior country towards Tongue and Barvas, the gneiss is found passing into common argillaceous schist ; forming a com- pound rock, in its constituents not unlike that which has been described under the head of North Uist, but much less hard in texture. To describe it correctly, it may be said that a felspar much intermixed with quartz forms the one part, and common clay schist the other. Some- times the first substance predominates, at others the last, and as these vary, so the rock passes on the one hand into a gneiss, on the other into common clay slate. It differs from the compound rock of North Uist in being much less hard, the schist indeed generally retaining * Plate I. VOL. I. O 1^4 LEWIS. — GEOLOGY. its ordinary degree of softness and its fissile disposition. I need not repeat the general remarks formerly made on this transition ; the recurrence of other similar instances serves to prove that it is an appearance of no accidental nature or limited extent.* This rock occupies a very considerable tract in Lewis, occurring on various parts of the coast from Storno- way southwards. Were it possible to have access to the inland rocks in this quarter, there is little doubt that it would be found to extend vfery far within the country, here as well as at Stornoway. Froin Loch Shell to Loch Brolum it forms the whole range of cliffs, being mixed in an irregular manner with the common gneiss, and traversed, as that is, by granite veins. It is much con- torted and displaced, being also broken into arches and hollowed into caves, the higher pinnacles being the resort of the eagles with which this shore abounds. At Loch Brolum this mixed rock is gradually succeeded by a simple argil- laceous schist, the gneiss being at length totally excluded. It here coMains green compact felspar, and resembles precisely that soft schist which occurs at the entrance of Loch Maddy. Beyond this point I observed it no longer, the gneiss in its most common forms returning at Loch Valumis and continuing to the entrance of Loch Seaforth, where the coast line of the Lewis terminates. I observed but feW of those minor beds of the rocks which are of general occurrence in gneiss, and of which examples have been described in the other islands before examined. A body of limestone occurs at Gres, near the junction of the gneiss with the conglomerate to be hereafter described. It is however not easily examined, and it will probably be found to appertain to the red sandstone, since it is known to form partial deposits in similar * Since the period at which this was written I have often met with ai-gillaceous sclitst connected in the same manner with gneiss, and occupying tracts of various extent. It occurs thus in Sutherland, in lloss-shirc, and else\^hy account) of Rona at 5° 4!^', and of Darra ;it o", and the latitude vi' tlie former from a mean of bearings at 69? 9'. NORTH RONA. GENERAL DESCRIPTION. 205 Sulisker (or Barra) appears to be about half a mile in diameter, liaving a grassy slope towards the north, and presenting to the south a bluff face of 300 feet or more in height. It is inhabited only by sea birds, and principally by gannets, the exposed situation and the difficulty of landing, rendering it inexpedient to keep sheep on it, as is done, with no great profit indeed, in the Flannan isles. During one week in the breeding season it is visited for the sake of the feathers, by the tenant of both the islands, who resides in Lewis. The sea running high, I found it impossible to land, but approached sufficiently near to discern without dif- ficulty that it was composed of gneiss traversed by veins of grey and of reddish granite. Whatever else it may contain must remain to reward the labour of any future mineralogist who may meet with better weather than that which fell to my lot. Rona is accessible in one spot only, and even that with difficulty, from the long swell which is rarely alto- gether absent in this sea. The landing place is only the face of an irregular cliff, and it is necessary to be watchful for the moment to jump out on the first ledge of rock to which the boat is lifted by the wave. The removal of the sheep is a perilous operation, the animal being slung by the legs round the neck of a man and thus carried down the face of a rock where a false step exposes him to the risk of being either strangled or drowned. To find inhabitants on such an island is a strong proof, among many others, of the value of land in this country compared to that of labour. There are few parts of Britain where Rona would not be abandoned to the sea fowls that seem its proper tenants. The length of this island was estimated at a mile and I may add that tliere are some outstanding rocks not hiid down in any chart, and, anoong others, one to the N. W. of Barra at about a mile distance. Q06 NORTH RONA: — GENERAL DESCRIPTION. a quarter, and its breadth where widest at half a mile, the time not admitting of a more accurate measurement. Its position is nearly east and west, and at the western extremity the rocks run far out into long flat ledges : there is also a similar ledge towards the north partially covered with grass. The remainder of the island is sur- rounded by high cliffs more or less abrupt, perpendicular at the northern side, and there rising to an elevation of 400 feet or more. Numerous caverns, some of con- siderable magnitude, are seen in these cliffs ; while the contrast between the green foam of the vv^aves that break into them and the pitchy darkness of their deep abysses, united to the grey mist of the driving sky speckled with the bright wings of innumerable sea fowl, produces effects fitted for the pencil of Turner and of him alone. The violence and height of the mountainous seas which in winter break on this island are almost incredible. The dykes of the sheep folds are often thrown down, and stones of enormous bulk removed from their places, at elevations reaching to 200 feet above the high water mark ; so powerful is the breach of the sea. Thus the land is in a state of constant diminution at the western end, and the soil is here washed away for a considerable space. The island lies with a general declivity towards the south and presents an even swelling surface covered with ver- dure. The highest point is near the eastern extremity and does not seem to exceed 600 feet. To sit on this spot, whence no trace of human existence is visible, and to. contemplate from such narrow bounds the expanse of water every where meeting the sky, produces a feel- ing of solitude and abandonment like that of the deserted mariner on a distant rock. The ship on the ocean is a world in itself, There, even if alone, we seem to move towards the society we have left, but Rona is for ever fixed in the solitary sea. Some years have now past since this island was inhabited by several families, who Contrived to subsist NORTH UONA. GENERAL DESCRIPTION. 20? by uniting fishing to the produce of the soil. In at- tempting to land on a stormy day, all the men were lost by the upsetting of their boat, since which time it has been in the possession of a principal tenant in Lewis. It is now inhabited by one family only, consisting of six individuals, of which the female patriarch has been forty years on the island. The occupant of the farm is a cottar, cultivating it and tending fifty sheep for his employer, to whom he is bound for eight years ; an unnecessary precaution, since the nine chains of the Styx could afford no greater security than the sea that surrounds him, as he is not permitted to keep a boat. During a residence, now of seven years, he had, with the exception of a visit from the boat of the Fortmiee,* seen no face but that of his employer and his own family. Twice in the year, that part of the crop which is not consumed on the farm, together with the produce of the sheep and the feathers obtained from the sea fowl which he is bound to procure, are taken away by the boat from Lewis, and thus his communication with the external world is maintained. Fortunately he seemed to care but little for any thing out of the limits of his own narrow kingdom.+ In addition to the grain and potatoes required for the use of his family, he is allowed one cow, and receives for wages the value of two pounds sterling annually in the form of clothes. With this, the family, consisting of six in- dividuals, must contrive to clothe themselves ; how they * Then employed in cruising after the President in 1812. f On the appearance of our boat the women and children were seen running away to the cliffs to hide themselves, loaded with the very little moveable property they possessed, while the man and his son were employed in driving away the sheep. We might have imagined ourselves landing in an island of the Pacific Ocean. A few words of Gaelic soon recalled the latter, but it was some time before the females came from their retreat, very unlike in look to the in- habitants of a civilized world. 208 NORTH RONA. GENERAL DESCRIPTION. are clothed it is scarcely necessary to say ; covered they are not, nor did there appear to be a blanket in the house ; the only substitute for a bed being an excavation in the wall, strewed, as it seemed, with ashes and straw. Besides the produce of the farm they are supplied with aiiimal food, in the sea fowl and in the small coal fish (cuddies) which are taken with the rod; and thus, with all their disadvantages, are sure of abundant food, that with which their countiymen in the situation of small tenants are not always provided. At such a price is here valued the labour of three individuals, for which the farm finds full employment. The soil is of a good quahty, and produces barley oats and potatoes. The average surplus of corn remaining beyond the consumption of the family was stated at eight bolls of barley ; and this, united to the produce of the sheep, and an annual supply of eight stone of feathers, is, to the tenant, the value of North Rona. To him, who is one of the tacksmen of Lewis, the land is let for two pounds a year. There is no other w^ater in the island than that which is collected in pools from the rain, but there is no chance of any deficiency in this article. As there is no peat, turf is used for fuel and the oil of the cuddy for light ; but, with characteristic improvidence, there are no means of lighting the fire should it ever be ex- tinguished. Well may the vestals of this cottage watch the smoky embers and trim the dying lamp. Such is the violence of the wind in this region that not even the solid mass of a Highland hut can resist it. The house is therefore excavated in the earth, the wall required for the support of the roof scarcely rising two feet above the surface. The roof itself is but little raised above the level, and is covered with a great weight of turf, above which is the thatch ; the whole being surrounded with turf stacks to ward off the gales. The entrance to this t>ubterranean retreat is throuiih a NORTH RONA. — GENERAL DESCRIPTION. 209 lono;, dark, narrow and tortuous passage like the gallery of a mine, commencing by an aperture not three feet high and very difficult to find. With little trouble it might be effectually concealed ; nor, were the fire suppressed, could the existence of a house be suspected, the whole having the appearance of a collection of turf stacks and dunghils. Although our conference had lasted some time, none of the party discovered that it was held on the top of the house. It seemed to have been constructed for concealment from white bears or men more savage still, with a precaution, now at least useless. The interior strongly resembles that of a Kamschatkan hut ; receiving no other light than that from the smoke hole, being covered with ashes, festooned with strings of dried fish, filled with smoke, and having scarcely an article of furniture. Such is life in North Rona; and though the women and children were half naked, the mother old, and the wife deaf, they appeared to be contented, well fed, and little concerned about what the rest of the world was doing. It was still an object of curiosity to ascertain if beings so insulated had no desires to return to society and mingle once more with their fellow creatures. But though man is gregarious, the want of extended society is in a great measure the want of cultivated minds. Here the family was society enough, and to provide for the demands of the impending day, sufficient occupation. The inferior members of it seemed to know of no other world than North Rona, and the chief appeared to wish for httle that North Rona could not supply. The only desire that could be discovered after much inquiry, was that of getting his two younger children christened, and for this pui-pose he had resolved to visit Lewis when his period of residence was expired. I need not say to those who know the Highlanders, that their sense of rehgion is not limited to externals. Amid his solitude this poor man had not forgotten his duties, though excluded from VOL. T. P 210 NORTH RONA. GEOLOGY. the advantages of their social forms. Yet I shall not be surprised if after the accomplishment of his only wish he should again long for his now habitual home : and expect that some future visitor will twenty years hence find Kenneth Mac Cagie wearing out his life in the subterranean retreat of his better days. Like Sulisker, Rona consists of gneiss, alternating with beds of hornblende schist equalling or exceeding it in quantity, and traversed by granite veins. The gneiss is of the granitic character, resembling that of Lewis, and the hornblende schist is distinguished by the great profusion of garnets it contains. These are so abundant that the weathered rock sometimes presents an uniform red surface, the hornblende wasting away, while the more durable garnet continues protuberant above it. They are occasionally of a large size, attaining the diameter of an inch or more, and occupying also the veins of granite and of quartz which traverse the beds. In this case they are occasionally transparent, but always too much fissured to admit of being rendered ornamental by polishing. The most conspicuous of the granite veins is many yards in diameter, and extends from the landing place to the north side of the island, in a straight course nearly north and south. It is remarkable for the mag- nitude and beauty of the felspar it contains, and of which it affords specimens of much interest to collectors. This is of a salmon colour and pearly lustre, translucent, and reflecting much light from the interior laminse. Sometimes it is so intermixed with quartz as to form graphic granite of various aspects, and occasionally, as in East Rona, of a laminar structure. The quartz of this vein is also remarkable for the variety which it presents. It is sometimes grey and opaque, at others smoky brown and transparent, or white and opaque, NORTH RONA. GEOLOGY. 211 or perfectly transparent and colourless. Besides these, there occur large concretions of opalescent quartz, varying from a highly diluted to a more perfect milkiness, and occasionally tinged with blue, in which case the specimens possess considerable beauty. In other veins there are found concretions of felspar equally large and beautiful, of a French grey colour, accompanied by quartz of a similar tint, and, like the former, these are occasionally mixed in a graphic manner. It is not improbable that a more rigid search might add something, to the varieties at least, of these sub- stances ; but the rising of the wind and sea rendered a precipitate retreat necessary. The addition of a few specimens to the catalogue would have been dearly purchased by even a week's residence in the stormy and solitary abode of North Rona. 212 RONA. GENERAL DESCRIPTIOX RONA.* (EAST.) After the repeated and wearisome descriptions of islands of gneiss, scarcely any thing remains to give interest to the account of Rona, the geographical im- portance of which is howeA'er too' great to allow it to pass \^^thout notice. At the same time its connexion with Rasay gives it a claim on attention, since it becomes the connecting link between the division now under review and the group of the Trap islands which is about to follow. Its aspect at a distance is little engaging, even to a geologist; to whom its external configuration presents no promise of variety ; -while the evident indications of gneiss offer still less temptation to him who has already toiled through the uniformity of the Long Island. To an ordinary traveller it is even repulsive, presenting no picturesque features and but little verdure to checker or contrast \\'ith its gi'ey and sterile surface ; the very patches of bro^\Ti mountain pasture it possesses being almost lost to the eye amid the rocks which rise on all sides. Rona is five miles in length and less than one in breadth, forming a long parallel ridge prolonged from the northern part of Rasay, and geologically connected with it by the inteimediate island Maltey and some smaller rocky islets scattered in the sound by which they are divided. The greatest elevation does not seem any where to exceed 500 feet, the whole ridge being separated by deep irregular valleys into rocky hills much resembling in their general characters those of Coll. In proportion to its area it is among the most barren and unproductive spots in the Western islands ; con- ♦ Sfo tlu; Map of Sky aiul uImi the genenil Map. UOXA. GEOLOGY. G13 taining a very scanty proportion of arable ground, and being chiefly appropriated to the rearing of black cattle. Four small hai-bours are found on the west side, one of whicii, Archasig hirm, offers a convenient refuge for coasting vessels, with a double entrance ; but it is very little known except to the natives and the neighbouring islanders. It is very imperfectly laid down in ^Mackenzie's chart, nor does it appear to have been surveyed by him- self. For this reason and because it is tlie only station from which Rona can conveniently be examined, it may be proper to add a few words respecting this anchorage. The entrance is covered by a rocky islet by which the harbour is completely land-locked, so that vessels may ride securely in any wind and weather, as in a mill-pond, and in good holding ground. The passages are both narrow and beset with rocks, but as these are all visible at half tide, it is easy to steer safely through them : the southern one is most free. It is easily known, in running down the shore, by the mouth of a cave visible on the island before described. When to those advmitages it is added that fresh provisions and water may be pro- cured here, I may be suspected of imitating the narratives of the voyagers who have navigated the South seas; but those who know the country in question will be well aware of the pmctical value of this remark. There is so much irregularity in the positions of the gneiss that it is impossible to give any general account of them, nor is any advantage to be gained by detailing the numerous changes they undergo. On the eastern side there will sometimes be found a great sequence of very straight beds dipping uniformly towards the east, while on the western they lie in a contrary direction ; the two meeting in the middle of the island like the roof of a house. In other places the same beds will be found reversed, the eastern beds dipping to the west, 214 RONA. GEOLOGY. and vice versa ; or they undergo changes still more intricate, displaying those wavings and contortions of which so many examples have already been recorded. These rocks are as usual traversed by granite veins, which, as in Coll and elsewhere, frequently present the graphic character ; and they alternate with simple hornblende schist, or with that variety in which felspar forms an mgredient. The granite veins appear so much blended with the rock that it is often difficult to trace the line of separation. In one or two instances the graphic granite presents a peculiarity of structure already noticed in North Rona, consisting of alternate laminae of quartz and felspar ; the former being occasionally diminished after a certain space, so as to disappear in a thin edge. The varieties of this gneiss are so numerous as not to admit of description, but it may be remarked, that like that of the Long Island, it generally possesses the granitic character, being large grained ; differing however in containing mica where that contains hornblende : the quartz and felspar are nevertheless predominant, and are often indeed the only substances entering into its com- position. Like the gneiss of Tirey, lona, and Harris, it frequently contains green compact felspar ramifying in different directions with much minuteness of sub- division. It is also conspicuous in many places for the great proportion of quartz it contains, this mineral possessing the chalcedonic aspect so common in gneiss. In some instances the rocks are entirely formed of alter- nating layers of this substance with felspar, with mica, or with hornblende schist, exhibiting specimens of con- siderable singularity. It may be further remarked that the felspar is generally red, and that the predo- minance of this colour gives a peculiar appearance to all the rocks of the island. The felspar found in the veins, like that already described in the Long Island, is often in large con- RONA. MINERALS. 215 cretions, which are always connected with the graphic mixture of quartz and felspar before mentioned. It is of a brownish-red colour and glassy lustre, and is intersected by opaque threads ; a circumstance common in this variety of felspar. The quartz, independently of the aspect above men- tioned, is often also remarkable for a green colour, which is generally dull, and appears to arise from fibres and laminae of the green felspar. It occasionally also contains mica, as well as hornblende ; while, being of a nearly crystalline transparency, it transmits their colours, acquiring thus a fallacious hue of green or black. In similar circumstances it often appears of a brick red from an intimate mixture of felspar. Coloured quartz of the usual character is also found in different places, and most abundantly on the skirts of the hills near Archasig vore. It varies from pink to dark reddish purple, the latter adding a variety of no very common occurrence to those already described on former occasions. In the natural cavities of the hornblende schist that mineral is sometimes found crystallized, but in the specimens which I procured the prisms were without regular summits. I have only to add that tetraedral grouped crystaliJ of oxidulous iron are not unfrequent in the granite veins. 216 REMARKS ON THE GNEISS ISLANDS. CONCLUDING REMARKS on the GNEISS ISLANDS. Although the tracts thus described comprise the chief masses of gneiss which occur in the Western Isles they do not include the whole, as will appear in the account of those islands which are to follow. The complicated structure of these rendered it proper to arrange them in a separate division. But in consider- ing those portions which consist of gneiss, there appear no circumstances requiring such notice as to render it necessary to defer this general comparison. From the dispersed nature of the preceding remarks on this rock it will be useful to bring the whole of its leading characters into one general view : a proceeding the more necessary as they appear never to have been clearly defined. It is not however in this view pretended to give a complete history of gneiss, since the remarks are only deduced from investigations limited to Scotland. They will still serve as contributions towards a more perfect one at some future period. The great, or picturesque features of gneiss present every possible variety. It often exhibits a dead level for a consi- derable space; as in Tirey, Benbecula, and other islands above described ; the only access obtained to the naked rock being from some pool of water or accidental breach of the surface. Occasionally, as in Lewis, protuberant masses are seen breaking through the soil. These become in other situations, as in Coll and Rona, so numerous, that, on a general view, nothing but a continuous extent of rock can be seen ; the small quantity of herbage, with the occasional lakes that occupy the intermediate spaces, being only visible in the immediate vicinity of the spec- tator. These rocky hills rarely exceed an hundred GENERAL KEMARKS ON GNEISS. 217 feet in height. In the northern and central parts of Scotland, the prevailing features of the country are, like those of Cornwall, undulating ; and the gneiss is generally covered with wet moory soil or with peat. These undulations gradually increase in height, as- suming the mountainous character and displaying broken faces of rock. In further progress they produce a craggy and abrupt outline ; while the mountains on the western coast attain an elevation equalling the general average of those throughout the country. Loch Hourn is par- ticularly distinguished by the height and ruggedness of the hills that surround it ; among which the district of Knoydart is pre-eminent, forming indeed the wildest tract in all Scotland. It will be immediately seen, that there are two prin- cipal varieties of gneiss ; the one of a granitic and the other of a schistose structure. From the latter a soil is formed, and general features produced, scarcely differ- ing from those which occur where micaceous schist is the substratum. The former is remarkable for its indestructibility, and hence arises the pecuhar nakedness of the countries that are composed of it. Considering its near resemblance to granite, a rock not often re- markable for braving the effects of time and weather, the causes of this power of resistance are not obvious: to a certain extent they may consist in the absence of fissures, denying access to frost. To this latter circumstance is owing the want of springs, so conspicuous throughout the Long Island; and the same considera- tion explains the deficiency of recent alluvia, so general in the islands of this group.* * A striking instance of the differences of soil resulting from tiiis distinction occurs at Strontian and in the adjoining land of Morven ; the common boundary that separates the gneiss and granite being rendered visible at a distance by the transition from a brown and heathy to a green and grassy covering : the latter, I need scarcely say, lies on the granite. 218 GENERAL REMARKS ON GNEISS. The stratified disposition of gneiss, and its conformity to the general bearing of the Scottish strata, have already been noticed. The causes of the obscurity which occasionally attends it must also have been apparent ; but it may be added that this obscurity is almost pecuhar to the granitic variety, and that the schistose is generally disposed with as great a degree of regularity as the analogous rocks, micaceous schist, quartz rock, and clay slate. It is scarcely necessary to repeat, that every possible variation of dip is combined with this uncertainty of direction. The flexures present an endless variety, and, like the other irregularities, are almost limited to the granitic division. They have been fully described where they occurred. All the varieties of gneiss are occasionally intersected by granite veins, and they are indeed almost characteristic of this rock ; being rarely absent for any considerable space, and seldom traversing micaceous schist unless under circumstances where they can be traced to some neighbouring mass of granite. They are however most abundant in the granitic division. They are infinitely various in size and in the number and intricacy of their ramifications ; and it is further worthy of remark, that the contortions of any mass of gneiss are always proportioned to the number and importance of those which it contains.* Hence it is that the schistose is more free from contortions than the granitic variety. It is nevertheless proper to make an exception * As almost every part of Scotland presents examples to illustrate this remark it is unnecessarj to quote the places where they occur. But the gneiss of Strontian offers an instance too important to pass unnoticed. The whole of the surrounding country is formed of beds holding a rectilinear course and presenting an undisturbed stratification, while they contain very few granite veins. But in the vicinity of the granite of that district the veins become numerous, and here the re- gularity of the gneiss ceases, while it also assumes a character more decidedly granitic. GENERAL REMARKS ON GNEISS. 219 respecting those beds of gneiss whicli alternate with other rocks, such as clay slate ; these, as far as I have observed, never containing veins. In some va- rieties of gneiss they are so abundant as nearly to exclude the original rock, so that the mass presents little else than a congeries of veins. An instance of this nature occurs in the Flannan isles, but the most strikino- are to be seen on the north west coast between Loch Laxford and Cape Wrath. The latter spot is no less remarkable for its picturesque grandeur than for the perfect manner in which it displays this circumstance ; the cliffs being free from lichens and unaltered by the weather, so that all the parts are as visible as in an artificial section. The hornblende schist and the gneiss are broken into pieces and entangled among the veins in the same manner as the stratified rocks are in the trap of Sky ;* but with infinitely greater intricacy, so as rather to resemble a red and white veined marble with imbedded fragments of black. These fragments do not seem to form a twentieth part of the whole mass ; while the progress of the different veins, and their effects in producing the disturbance, are as distinct as in an ordinary hand specimen. If the intricacy of the ramifications, and the intersection of one set of veins by a second and a third of different textures, present an argument in favour of a succession of these at several periods, there is here no want of such evidence. I have only to regret that I cannot give a correct view instead of the very slender sketch subjoined : the limits of the plates do not admit of a more perfect representation.'!^ Whether these granite veins are connected with masses * It is not easy to admit the arguments derived from these ap- pearances in favour of the igneous origin of trap and refuse them in the instance of granite. There is in truth no difference in the cases but that which arises from the difference of tlie materials engaged. t PI. XXXI. fig. 1. 220 GENERAL UEMAKKS ON GNEISS, of granite in all cases, can not be determined. In some instances, as in Perthshire where the gneiss reposes on granite, it is probable that they proceed from it; but it has already been seen that there are no traces of that rock in the Long Island. That is however no proof of its non-existence, and the circumstance of the veins being always present when the gneiss reposes on granite, and absent when another rock is interposed, renders it probable that in these cases granite, though invisible, is still present. The following considerations render it probable that the granite veins which traverse gneiss are posterior to the including rock, and formed under circumstances analogous to those under which other granite veins have intruded into the schistose rocks with which they interfere. They are accompanied by fractures or contortions of the gneiss, of such a nature as to prove that it once possessed a condition capable of yielding in different ways to external force, while these appearances are also proportioned to the number and intricacy of the veins. In the schistose varieties which yield easily in the direction of the laminae, the veins frequently hold a parallel course to these, while an occasional flexure occurs in those cases where the vein crosses them ; the edges being incurvated from the thicker part, or the root of the vein, towards its termination. Lastly, in cases, of which an example was described in Tirey, where a vein traverses a mass of limestone included in the gneiss, it disturbs that substance as well as the surrounding rock ; and in another parallel instance noticed in Scalpa, where the included substance is serpentine, the vein itself undergoes a change by participating in the nature of that rock during its passage. It may now be remarked respecting these veins, that although they sometimes resemble ordinary granite, they more generally possess a distinct character, consisting GENERAL UEMARKS ON GNEISS. 221 chiefly in the larger size and more decided crystal- lization of their constituent parts. It is in these that the large concretions of mica and of felspar are almost always found. I have rarely observed that in the granite veins of gneiss there is any difference of texture between the middle and the exterior parts, although in those that tra- verse other rocks and can be traced to granite masses, this feature is common. The same rule holds respecting the larger and smaller veins, Avhich in gneiss possess indif- ferently a similar texture, while in other rocks the texture is minute, generally, in proportion to the vein. Many of the veins in gneiss consist of felspar and quartz with- out mica or hornblende ; in all, these minerals are pre- dominant. Graphic granite is much more frequent in the veins that traverse gneiss than in the others, although not absolutely limited to these. The felspar is generally the predominant substance in this class of veins and often presents a common polarity throughout the whole mass, as already noticed in Coll. The mutual disposition of the felspar and quartz is various. Occasionally it is partially laminar, as in Rona ; more commonly the quartz is in prismatic forms, triangular or hexagonal, or occa- sionally, even hollow and filled with felspar. In a very few instances the summits of the quartz crystals are per- fect, and protrude into a vacant space. From considering the relative forms of the quartz and felspar it will some- times appear that the one and sometimes that the other has first crystallized, and thus determined the shape of its associate. Gneiss, considered as a rock, alternates with many substances generally inferior in quantity, to which the arbitrary term subordinate has been applied. Sometimes however it is inferior in quantity to those very rocks, and might therefore with equal justice be considered the subordinate substance. It is difticult to draw a sufficient line of distinction between those altomations which may 222 GENERAL REMARKS ON GNEISS. be supposed to form a part of gneiss, considered as a geolo- gical formation, and those which ought to be viewed as alternating formations. Perhaps the following criterion may be deemed a just one. Where the interstratified substances follow all its contortions and are traversed by the same granite veins, the whole may be considered as one rock-formation, and may be included in geological description under the common term gneiss. On the con- trary, when the other rocks that accompany it form distinct masses, however slightly confounded at the point of change, are free from the irregularities and veins that attend the gneiss, or are succeeded after such alternation by independent masses of the same rock, or of others usually associated with them, they may be supposed to belong to a different series. In the first of these divisions, hornblende schist is by far the most abundant rock, and it appears to predominate chiefly where the gneiss itself contains hornblende as an ingredient. Under this head are ranked the compound schists sometimes known by the name of primitive green- stone. Actinolite schist occurs in a similar manner, but is rare. Micaceous schist must also be ranked with these substances, however difficult it may sometimes be to dis- tinguish it from the schistose varieties of gneiss. Lime- stone also occurs in the same manner, but in large irre- gular masses more frequently than in distinct beds. Lastly, quartz is occasionally found interstratified with gneiss, sometimes simple, at others interspersed with crystals of felspar or with hornblende and felspar both. The circumstances under which it is undistinguishable from granite have already been stated and do not justify the notion that this rock is actually interstratified with it, either as part of the series or as a distinctly alternating substance. But the most important part of the geological history of gneiss is that which is included under the second division and which relates to its position with regard GENERAL REMARKS ON GNEISS. 223 to other rocks, whether in the order of precedence, suc- cession, or alternation. It seems to occur in immediate subjacence to all the primary strata, and, in Scotland at least, to the secondary also. The instances in which it is succeeded by micaceous schist and quartz rock are so common as not to need enumeration. In Lewis and North Uist, it immediately precedes argillaceous schist, as it also does in several other parts of Scotland. In Perth- shire and in Sutherland it is followed by primary lime- stone, and by the primary red sandstone ; and, in Morven, it is covered by an extensive tract of that conchiferous limestone accompanied by white sandstone and coal, which occurs in a dispersed manner throughout this coast. Occasionally it reposes on granite, but not exclusively ; since the granite of Scotland is followed, in some situation or other, by every one of the primary strata: and that it does not necessarily succeed any one rock, will be proved by the history of its alternations. With micaceous schist and quartz rock these are so frequent that examples need not be pointed out. In Isla the gneiss is imbedded in masses of argillaceous schist, or occurs in frequent repetitions with that rock ; while in lona, the schist which is interposed between the granite and the gneiss, is also imbedded in the latter, as it fre- quently moreover is found, at Loch Eribol, Loch Carron, and in other places, in a much more extensive and un- questionable manner. In Perthshire the gneiss and the limestone alternate on so large a scale that the latter cannot be considered as a subordinate rock. The gneiss of Sutherland and Ross-shire also alternate with limestone, and in the same districts there is a perpetual interchange of its beds with those of the primary red sandstone and of quartz rock. In Sky it has been shown to graduate into these latter rocks, as well as into argillaceous and chlorite schists. With respect to its history as a rock species, the most 2 224 GENERAL REMARKS ON GNEISS. important question is, to what extent it partakes of the nature of a mechanical deposit, or whether it may be considered as purely chemical. There are in this case two grounds of judgment, the form of the rock and its internal structure. In the first circumstance it resembles those rocks of later origin of which the mechanical nature is unquestionable. But even these present in many cases, whether they are primary or secondary, the indications of a chemical nature combined with a mechanical struc- ture. So far therefore the mineral composition of gneiss presents no argument against the belief that it was ori- ginally deposited in a manner similar to that of the other stratified rocks ; a supposition confirmed by the prolonged and parallel direction which it bears to these throughout the whole of Scotland. A stronger confirmation of this is supplied by the appearances of some of the rocks with which it alternates. It will hereafter appear in the history of the red primary sandstone, that some of the beds of that substance bear the same marks of undulation on the surface which characterize the secondary sand- stone and prove its deposition from water, these being found in alternation with the gneiss of that district in which it occurs. It will also be shown in the history of Garvh Island, that a rock containing organic remains is found in a sij^nilar position ; both instances equally proving that like those strata it must originally have been deposited from water, whatever changes it may since have undergone. With respect to internal character, it has not hitherto, I believe, presented any decided marks of that mechanical arrangement, which, with the exception perhaps of limestone, are occasionally present in every other stratified rock. I shall hereafter show that the parallelism of mica is not a proof of such arrangement, since that mineral occurs in this manner in veins of porphyry and of trap. The conglomerate gneiss described in Rasay, and also found in Morven, ap])ears to be of posterior formation, and to be analogous to the local GENERAL REMARKS ON GNEISS. 225 attached breccias so frequent in limestone. But this is not the place, under tlie present dearth of information on this and similar subjects, to enter into any further speculations, and I shall therefore proceed to such an arrangement of the individuals of this family as my present state of information admits. Before enumerating the several rocks here united under the general term of gneiss, it is however proper to say that the limits of the definition have been con- siderably extended. This seems unavoidable, since the vaiying composition of the rock and the gradual nature of the changes it undergoes, render it impossible to apply separate terms to each variety, without accumulating a load of titles which would encumber instead of elucidating the subject. Nor is there any reason why the definition should not be so extended, since no rigidity has been held necessary in the case of other compound rocks where variations even greater are of common occurrence. In enumerating the varieties I have however separated the most anomalous from those which, with greater simpli- city and regularity of structure, exhibit in a great mea- sure, if not entirely, a composition con'esponding to the ordinaiy definition of this substance. It is for geologists to receive or reject this arrangement as they shall see right ; it can only be offered as a very imperfect attempt towards the attainment of the object, since it is founded on observations limited not only to Scotland but to a small part of that country. In the first division are placed all those of which the composition may be considered regular, as being identical with that of granite : the second contains those that are characterized chiefly by the presence of compact felspar ; and the third includes all which, with a community of structure and geological position, present a different variety or combination of ingredients : of these last the greater VOL. I. Q 226 GENERAL REMARKS ON GNEISS. number will be found to pass by insensible degrees into the more regular kinds. The first division is subdivided into three parts, each of them being characterized by a peculiarity of structure. The granitic subdivision is that which prevails through- out the islands now described, and it is characterized, not only by a large grain and imperfectly foliated struc- ture, but by frequent partial transitions into granite, from which, when in detached specimens, it cannot sometimes be distinguished. The second, or schistose subdivision, occurs principally on the mainland of Scotland, in numerous situations ; alternating with and graduating into micaceous schist and into quartz rock ; in some cases so frequently, that it is impossible, in describing or in mapping a given district, to say under which head the rocks ought to be enumerated. In its general aspect it is small grained ; with a granular texture when connected with quartz rock, and with a distinctly laminar one when it passes into micaceous schist. The felspar can in many cases only be distinguished from the quartz by its decomposition on the weathered surfaces; and, when these are not acces- sible, this gneiss is easily confounded with the one or the other of the two rocks above mentioned. The last subdivision, or the laminar, seems to be of more limited occvu'rence, but it may be seen in Rona, in Sky, in Ardgower, and in other places. It is charac- terized by the laminar alternating disposition of the ingre- dients; the specimens often exhibiting in consequence of this airangement, singular and beautiful combinations of colour. It will be perceived that, as in the case of granite, I have here admitted hornblende together with mica as partici- prtbiio' lu till.' composition of regular gneiss. In fact this mineral is more prevalent than mica in the gneiss of the Western isles ; nor does there appear any reason GENERAL REMARKS ON GNEISS. 227 in this case more than in that of granite, for creating a new species. While the component parts vary in both cases, the continuity and geological relations of both the rocks continue unaltered. On a first view the varieties in the aspect of gneiss are so numerous that it would appear impossible to refer them all to the following list. Yet, when strictly examined, it will be found that these diversities, as in the case of granite, arise from variations in colour, proportion, dispo- sition, and size of the constituent parts ; circumstances evidently capable, under their possible combinations, of producing varieties that may fairly be considered infinite. I have only to add as a preliminary to the synoptic table that the second division contains two subdivisions, and that the third presents subdivisions of structure similar to the first, although not sufficiently constant, or ex- tensive in a geological view, to require a formal arrange- ment in the present sketch. 228 SYNOPSIS OF GNEISS. SYNOPSIS OF GNEISS. FIRST DIVISION. Of regular composition, containing at least three of the four minerals, quartz, felspar, mica and hornblende. First Subdivision. — Granitic. Resembling granite, i. e. large grained and often losing the foliated structure. A. Quartz, felspar, mica. B. Quartz, felspar, hornblende. C. Quartz, felspar, mica, hornblende. These varieties abound in the Long Island. They some- times contain superadded crystals of felspar, thus forming the porphyritic gneiss of some authors. Second Subdivision. — Schistose. The structure laminar, like that of micaceous schist, or granular v^^ith a slight laminar tendency, like that of quartz rock: — finegrained. A. White felspar and quartz in minute grains intimately mixed, with rare scales of mica. The position of the mica determines the foliated structure, which is how- ever often so very indistinct that the specimens can scarcely be distinguished from quartz rock. B. The mixture of felspar and quartz finely granular as in the former, but the mica so abundant as to cause it to resemble certain varieties of micaceous schist. C. The mica so abundant as to form distinct continuous laminae; and as in these cases it is often very difficult to distinguish the felspar from the quartz, the specimens are easily confounded with common micaceous schist. SYNOPSIS OF GNEISS. 9,29 D. A schist of foliated mica, with interspersed and large irregular crystals of felspar ; the quartz being scarcely discernible. It may be added that the whole of this subdivision present transitions from gneiss into quartz rock and into micaceous schist. Where the felspar is red they are easily distinguished : when white, it is much more difficult to recognise them. I may also add that hornblende is, as in the first division, an occasional ingredient. This variety occurs abundantly on the west coast of Scotland, in Rannoch, and in the middle Highland districts of Atholl and Badenoch. Third Subdivision. — Laminar. In the two former subdivisions, either the whole mass has a granular structure combined with the foliated, the latter arising from the position of the mica, or the horn- blende ; or else the quartz and felspar form one granular mass, separated into laminae more or less defined, by the mica, or by the hornblende. In the present, each substance occupies a distinct lamina, the quartz and the felspar being separated ; sometimes remaining in contact, at others being- divided by intervening laminae of mica or of hornblende. This variety is generally remarkable from the contrast and disposition of the substances, and the quartz fre- c|uently puts on the muddy aspect of chalcedony. * A. Quartz and felspar in alternating laminae. B. Quartz, feUpar and mica, similarly alternating. C. Quartz, felspar and hornblende, disposed in the same manner. * D. Felspar and hornblende ni alternating laminse. The varieties A, B, are abundant in Glen Elg, Rona and Ardgower; the third occurs occasionally in various situations. The quartz is also found alternating with mica * These niij^ht ^vitll perhaps inoie propriety be placed in tiie thiid division. 230 SYNOPSIS OF GNEISS. only or with hornblende only, in the same situations ; but it is scarcely necessary to specify these varieties as they appear to be very limited in extent. With respect to the first division I may add, that the several varieties enumerated under it are occasionally found passing into each other, in all situations where gneiss occurs ; notwithstanding the leading prevalence of one or other of the subdivisions. SECOND DIVISION. Of irregular composition, containing compacted and compact felspar. First Subdivision. Containing compacted felspar united to the ordinary ingredients of gneiss ; the structure granitic or else par- tially schistose. A. Compacted granular felspar with or without quartz, and interlaminated with hornblende. B. The same with mica instead of hornblende. C. The same with both mica and hornblende. The varieties here included are far less common than the granitic or schistose gneiss, but they occur never- theless in considerable quantity in Sutherland and in Koss- shire, very often in company with those of the following subdivision. The essential distinction between them and the ordinary varieties of gneiss consists in the condition of the felspar, which is disposed in small crystalline par- ticles, often of a glassy lustre, compacted into a dense and somewhat granular aggregate. Hence it is distin- guished by the name of compacted felspar, a term which expresses this peculiarity without confounding it with ordinary compact felspar. These rocks all present a very decided character by which they are easily distinguished from the more common varieties of gneiss. SYNOPSIS OF GNEISS. 231 Second Subdivision. Consisting of compact felspar united to the ordinary ingredients of gneiss. In structure it sometimes resembles common gneiss, but more frequently its fracture is like that of the non-fissile schists, presenting no indication of laminae. A. Compact felspar with hornblende. B. The same with hornblende and mica. C. Compacted and compact felspar united. D. A granular and laminated mixture of compact felspar of different colours. — Perhaps this rock should rather be arranged with the compact felspars. E. This includes those varieties of gneiss formerly de- scribed, in which compact felspar is superadded to all the ordinary ingredients. The substances ranked in this subdivision are frequently traversed by veins of compact felspai, often reticulating in an intricate manner, and so numerous as to form a large proportion of the rock. The predominant colours in this compact felspar are various shades of grey, but the green variety formerly described is also very common. They occur abundantly, sometimes in connexion with the varieties of the first subdivision, in Sutherland and Ross- shire ; and are particularly conspicuous on the borders of Loch Mare, where they are associated with a fine hornblende schist that occasionally passes into a sub- stance scarcely distinguishable from the argillaceous slates. They have already been pointed out in North Uist and West Rona. THIRD DIVISION. Of irregular composition, being either deficient in the number of ingredients required to meet the definition of 232 SYNOPSIS OF GNEISS. gneiss, or containing some substance not included in that definition. A. Quartz and felspar ; simply laminar and at the same time granular. The foliated disposition here results from the crystalline position of the felspar. B. Hornblende and felspar, foliated and sometimes im- perfectly schistose. Analogy and geological con- nexions claim a place here for this rock ; it is however the primitive greenstone of some and the hornblende schist of other authors. C. Felspar and mica. — Long island. D. Felspar and clay slate. — Isla, Lewis. E. Felspar and chlorite schist. — Gigha, Sky. F. Felspar, quartz and chlorite schist. — Sky. G. Felspar, quartz and clay slate.' — North Uist. H. Felspar, quartz and talc. — Scalpa, (West.) L A granular mixture of felspar and quartz in one lamina and clay slate in another. K. The same with chlorite schist or greywack^ slate instead of clay slate. — Sky. L. Compact quartz with imbedded grains of felspar, in one lamina, and the same schists in the other. — Sky. M. Schistose felspar containing crystals of hornblende iy.terspersed. N. Aotinolite occupying the place of hornblende. — Sutherland. Of all these I may remark, that the geological position and general features are the same as those of the most regular gneiss, and that they often pass into the regular varieties.* * It is perhaps superfluous to remark, that although I have thus distingiushed the varieties of gneiss hy fixed divisions, there are, as in all cases of compound rocks, intermediate gradations which cannot be decidedly referred to either. But I may observe that many other combinations probably exist, and that an ideal catalogue of much greater extent might easily liave been formed. The present cnumera- SYNOPSIS OF GNEISS. Q3S No division is here made of those varieties which con- tain occasional minerals, however abundant, or in what- ever manner disposed, since these must be considered as accidental not essential substances. The followins: mi- nerals are those of most usual occurrence : — Garnet — This is found either diffused through the mass, or crystallized and disposed in a laminar manner, or irre- gularly scattered. Actinolile. — This mineral occurs under various forms, sometimes, as above noticed, as a substitute for hornblende. Quartz. — The quartz occurring in gneiss is often marked by peculiar characters. The most common is a slight opacity varying from a waxy to a chalcedonic and to an opalescent appearance. This is particularly the case in the laminar subdivision. It has sometimes but improperly been termed chalcedony. The milk quartz of mineralo- gists, of whatever colour, belongs to this variety, and is, 1 believe, always an inmate of gneiss. It also occurs very finely granular, as was noticed in Harris. In the vicinity of Loch Mare, fetid quartz, similar to that of Nantes, is not uncommon, its smell on friction somewhat resembling that of putrid sea weed. The quartz is also found of various colours in the gneiss of the north-western coast and in that of the Long Isle. The prevailing are the various shades of ash grey, varying gradually from the lightest tint to jet black, in which last state it occurs in the gneiss of Ben Lair in Ross-shire ; but very rarely. Next to these the most common colours are reds, varying from a pale claret to a dilute pink. French grey is less common ; it was mentioned as found in North Rona, and it also occurs in the gneiss of Glen Tilt. In one of the islands of Loch Hourn I observed it of a dilute green, tion has been rigidly limited to the varieties actually observed. It is evident that some of them would equally admit of Ijeing ranked with other rocks, but such are the transitions of these compounded bodies tliat every arrangement must be subject to this kind of imperfection. 234! SYNOPSIS OF GNEISS, passing gradually into dark bottle green and thus forming the prase of mineralogists ; the colour appearing to be derived from the actinolite schist with which it was as- sociated in the rock. Felspar. — Gneiss appears to be the natural repository of the principal varieties of this substance, which is some- times, but not necessarily, connected with the granite veins. Oxidulous Iron. — This occurs so abundantly at times as to form a constituent part of the rock. Hornblende — Occurs chiefly as a part of the alternating beds of hornblende schist, but is occasionally found in distinct concretions and in the form of perfect crystals. Fluor Spar — Is not common, but occurs in the gneiss of Sutherland, sometimes aggregated in lumps, at others diffused throughout with the other ingredients. Zircon. — I have also found this mineral in the gneiss of Sutherland. Tourmalin. — This seems to occur but seldom ; the crystals, though small, are in general extremely perfect. Epidote. — This mineral occurs in the gneiss of Suther- land, often in such abundance as to form a constituent of the rock. Pyrites — Is sometimes, but rarely, found dispersed ; and commonly in those varieties that contain hornblende. Moli/bdena. — This rare mineral is found in the gneiss of Baffin's Three islands, dispersed in minute grains among the other constituent parts. Many other minerals have been occasionally described as found in gneiss, but the true repositories of these are the granite veins : or, at least, sufficient care has not been taken so to distinguish between the two cases, as to admit of their being here enumerated. The pre- ceding list includes those which I have observed in the gneiss itself. INTRODUCTION TO THE TRAP ISLANDS. 9^35 INTRODUCTORY REMARKS on the TRAP ISLANDS. In giving to this group the name of the Trap islands I have been guided by the nature of the predominant rock; although it will appear when the individuals are described, that some of them, as Pabba for example, contain no masses of that substance. But since, together with trap, some of these islands present conspicuous and interesting tracts both of the primary and secondary rocks, the illustration of which depends in a great mea- sure on the structure of all the neighbouring parts jointly considered ; the few here included, in which that rock is not present, could not have been omitted without inconvenience : the deficiency of arrangement is fully com- pensated by the advantage gained in point of illustration. Before proceeding to consider these islands in detail, it will not be unprofitable to take a general view of the relations which they bear to each other, and to the con- tinent near which they lie. To aid this view the general Map may be consulted. The trap is obviously divided into two principal groups, Sky being the centre of the one and Mull of the other ; these being however connected by detached masses occu- pying either the intermediate islands or parts of the con- tinent. The Shiant isles and the remarkable rocks at Loch Maddy formerly described, are found at the outskirts of this boundary, from which however St. Kilda may be excluded, on account of its total want of probable connexion. The first feature which arrests the attention in con- sidering these islands, is the nonconformity of outline * See the table at the commencement of this work, and also the general Map. 236 INTRODUCTION TO THE TRAP ISLANDS. they present to tlie general north-easterly bearings of the coasts, which have already been stated in a cursory way to depend on the direction of the strata, and will hereafter be more fully seen to proceed from that cir- cumstance. This contrast is peculiarly remarkable in Sky, where the larger part of the island presents a ten- dency different from that of the smaller portion. The former consists of trap ; whereas the latter is formed of the stratified rocks both primary and secondary, and maintains its general position with respect to the con- tinent; preserving, as will hereafter be shown, the regular directions of those rocks where they occur in more continuous masses. The nonconformity of the outline of Mull is less apparent; yet its longest shore, which together with the opposite land of Morven includes the Sound, will also be seen to form a large angle with the predominant lines of the western coast. On the same map the extent of the secondary strata may be traced, and it is apparent that there is a very general coincidence between the two classes of rock, or that the trap is confined, with but slight exceptions, within the same limits as the secondary region. The only portion at much variance with that rule is the porphyritic district of Glenco, on the mainland ; but of the real connexion of this with the Trap islands there are considerable doubts, which I shall have occasion to state hereafter. Our present knowledge of the trap rocks is perhaps not yet sufficiently extensive to allow us to speculate on this connexion between them and the secondary strata. We have no reasons a priori to expect that they should be found in this situation exclusively, nor is the rule indeed by any means universal ; yet it is remarkable that in Scotland as well as in the neiglibouring country, Ireland, almost all the great overlying districts of trap are pnncl|r.Vlly connected with these strata. If we con- sider the probable causes in which they have originated, INTRODUCTION TO THE TRAP ISLANDS. 237 there is no apparent reason why they should not be equally found overlying the rocks of primary formation ; nor indeed, on any view of the causes of their deposition, is this circumstance to be explained ; since, being the uppermost of all rocks and the last in point of time, they might be expected equally to cover all those whose limits in elevation do not exceed the utmost height at which they are found to exist. Although this connexion should even prove very partial it is not the less worthy of the attention of geologists ; but the solution, like that of a thousand other ditiiculties which attend this infant science, must be expected from future acquisitions of knowledge. Whatever connexions more intimate than those at present visible, may exist among the several detached portions of trap, as tliey occupy either the islands or the shores of the neighbouring continent, are for ever con- cealed from us by the insuperable obstacle which the ocean throws in our way. Hence it is impossible to judge whether the Maddies and the Shiant isles are now connected beneath the sea with Sky, or whether they have ever been so united. The occurrence of St. Kilda, so far remote from the whole, might perhaps rather induce us to adopt the contrary belief, and to consider them as independent formations. Contemplating the Trap islands in this general view, the occurrence of the veins of that substance is not the least interesting part of the subject. These are notoriously common in the Western islands. I have pointed out many of them already in the Gneiss islands, and they will here- after be shown to be even more frequent in the other islands of this sea. Wherever they are found, they seem to abound most in the vicinity of the great masses of trap. As proofs of this, I may quote their greater rarity in the remote parts of the Lewis than in the Schistose islands, which lie in the vicinity of Mull ; and their fre- quency in Arran and the stratified parts of Sky, compared 238 INTRODUCTION TO THE TRAP ISLANDS. with their more sparing occurrence as we recede from those central masses. I shall indeed hereafter show, that their numibers can scarcely be reckoned in the immediate vicinity of many of the masses of trap in Sky and in Arran ; while they disappear in succession as we remove from these, their progress being generally limited, although in a few instances surprisingly persevering.* Hence we may infer, that these veins are processes from the main bodies of trap ; and this view is occasionally confirmed by the facility with which they can be traced to their sources, examples of which are of frequent occurrence in Sky and in the islands on the coast of Lorn. It is not however pretended that this origin is universal, since it is equally certain that two distinct sets of trap veins exist; the posteriority of the one being proved by its traversing the other, as well as by its distinctly intersecting the great masses themselves. It is possible that many of the more remote and persistent veins may be of the secondaiy order, but of this we are not likely to obtain any proofs. I shall now proceed with the details of the individuals, commencing with Rasay, and treating of them successively in that order which, however irregular it may appear, seems most conducive to their mutual illustration. * The Argyllshire coast presents a striking illustration of this fact. They are exceedingly rare between the Mull of Cantyre and Crinan ; but beyond this they begin to prevail, and as we approach tiie great mass which covers Mid Lorn, they occur in great abundance, increasing in number and magnitude in proportion to their vicinity to that extensive tract of the parent rock. iiASAY. — genp:ral description. 239 RASAY.* The natural affinity of composition subsisting between the northern division of this island and Rona, has, toge- ther with their intimate geographical connexion, induced me to describe it next in the order of succession, and first therefore of the Trap islands. By adopting the course which I have followed in this and other cases, although the order of arrangement may at first sight often appear capricious, it will be seen that considerable facility is afforded towards understanding, not only the structure of the individuals, but the more important relations they bear to each other ; as well as in reducing their scattered and insulated materials into one whole. There are many obscurities in the composition of one island which can only be removed by the knowledge of another ; and by thus proceeding from a base to a superstructure, the reader will immediately comprehend many points which I did not arrive at till after much circuitous labour and many comparisons. Sky, the most prominent and import- ant feature in this group, is, from its construction, from the scattered nature of its details, and from the frequent disappearance of the regular strata in consequence of the presence of the irregular rocks, a fund of obscurity ; while, being the centre to which so many parts tend, it is the most in need of illustration. Rasay, though interesting also in itself, becomes here a principal object, by its collateral and secondary uses ; and its value in this respect will be hereafter apparent when I shall attempt to investigate the structure of the former island.f * Rasay — Raasay, properly — from Raa, a roe or deer. — Danish. See the Map of Sky. t So much in geological investigation depends on the truth of maps, that there is great reason to lament the general incorrectness of the maps and charts of this coast. In no instance is the defect more 240 RASAY. GENERAL DESCRIPTION. This island is estimated to be fifteen miles in length, and where widest, three in breadth. Neither of its longest shores differs much from an uniform line ; but the differ- ences, slight as they are, and therefore the less noted in the maps, are peculiarly important to a geologist, as they are connected with changes in the nature of the rocks, the relations of which they serve at the same time to compare and determine. It may be considered as forming a single ridge, though irregular and unequal in elevation at its different extre- mities ; the change, which is somewhat sudden, taking place near Brochel Castle and being accompanied by a corresponding difference in the rocks which form the two divisions. The average height of the highest and southern division may be estimated at 1000 feet or thereabout, and it presents, when viewed from the south-east, the outline of a high table land surmounted by the single flat-topped eminence of Dun Can, of which the height appears to attain about 1500 feet. But it declines towards the west by a general slope, terminating in low shores ; while the eastern side is, for the greater part, bounded by a long range of cliffs of a mural character, intermixed with those grassy slopes which are here, as in similar cases, the result of the degradation of the rocks. In the interior of the island, naiTOw as it is, are many irregular emi- nences, mixed with others of a character so particular as felt than in the island under review ; the inaccuracy of its map being so great, that it is almost impossible to reconcile any of tlie actual bearings with those that are given ; and, consequently, to pursue from place to place those detached portions of any individual rock which it is important to trace accurately. The same cause renders it impossible to give a true topographic detail of the rocks, but as great nicety in tiiis respect is not very essential, tlie reader must be content to take tlicm with that latitude, both of position and dimension, which alone is attain- able. There being a total want of an interior survey, there can of course be IK) local references. I have corrected some parts of the present noap which stood particularly in need of it, but they beiu' so small a proportion to the wliole, that it must still remain what it was, a mass of deformity. RASAY. — GENERAL DESCRIPTION'. 24l to be worthy of notice. These are long narrow ridges parallel to the sides of the island, divided by deep valleys in such a manner, that the toil of traversins: them can only be compared to that of alternately descending and surmounting the ridgy waves of a long and deep-rolling sea. This appearance is interesting independently of its general features ; as it will be found to be in a great measure regulated by the places of the porphyritic rocks which lie over the sandstone that constitutes the basis of the island.* The northern part of Rasay, consisting of gneiss, presents those naked and rounded, yet evenly disposed rocky eminences, which characterize Rona and the low islands formed of the same rock that have already been described in the beginning of this work. The west side of the island has a most uninteresting aspect ; presenting long ridges of grey rock ill diversified by the brown hue of the heath and the arid yellow of the Scirpus caespitosus, the joint tenants of similar soils. The east side is, on the contrary, covered with scattered farms ; each surrounded with its cultivated tract, and the whole diversified by towering rocks, formidable cliffs, and patches of brushwood. On this side, scenes of considerable gran- deur occur, generally marked by great breadth and simpli- city of manner, and by powerful eflfect ; at times however verging to an artificial character, in the architectural regularity of the flat sandstone cliffs, which are frequently split into columnar and conical forms, rising like towers above the deep dark sea that washes their bases. The houses perched on these summits seem more like the retreats of the birds that hover round them than the habitations of human beings ; the eye from below scarcely distinguishing them, far less their inhabitants. The grandeur of these long extended walls of rock is often varied by the enormous fractures and dislocations which have at different times taken place \ masses of immense bulk having been occasionaUy separated so as . * PI. XIII. fig. 6. VOL. I, R 242 RASAY. GEOLOGY. to form a second ridge below them ; while, in other places, huge piles of ruin cover their slopes with frag- ments, advancing far into the sea and strewing the shore with rocks. None of the islands, not even Sky itself, illustrates so strongly the magnitude of the changes that take place from the operation of daily causes ; changes however, which, although more palpable, are not perhaps more effectual than those which occur in many situations where they do not carry so strong and permanent a record with them. Excepting these, there are few marks of waste in the island ; as it gives rise to no rivers worthy of notice, and the mountain rains, reaching the sea soon after they have quitted the clouds by courses the most easy and direct, leave few traces of their ravages. At its southern extremity is found an alluvium of rolled stones, forming a sea bank of an origin which is not apparent; since it is not connected with any river, and is far too high to have been thrown up by the tides. A similar one, but of smaller extent, is found near Clachan. These are, possibly, the remains of some more extensive deposit of a diluvian nature ; a circumstance rarely occurring in the Western islands, but of which another example still more remarkable will hereafter be pointed out in Sky. In describing the geological structure of Rasay* I shall commence with the gneiss ; since by means of this rock it is connected with Rona, and since this is also the lowest substance in the island. It occupies the whole of the northern extremity, and is defined at its southern boun- dary by a line drawn from Brochel Castle in a N. by W. direction, passing through the Lake of the Reeds and crossing the narrow sound which separates Rasay from Flodda. This boundary is not however rectilinear, as the gneiss occasionally intrudes within that space, which, on * PI. XIII. %• 4, 5. RASAY. GEOLOGY. 243 account of the regular bearing of the strata that imme- diately follow it, we should have expected to find an un- interrupted mass of sandstone. On the eastern side of the island it appears to be disposed in beds of considerable regularity, conforming to the sandstone, lying with their elevated edges, as nearly as could be ascertained, in the direction of N. by W., and dipping E. by N. The angle may be taken on an average at 40°. I do not speak with confidence respecting the direction of the gneiss, since it does not appear to be disposed with that linear exactness so remarkable in Sky, nor, as in that island, to run with the same parallel nicety to the sandstone. On the con- trary, in many places, and particularly towards the nor- thern extremity of the island, its position becomes uncer- tain and irregular as in Rona. Having given a sufficient description of the mineral characters of this rock when speaking of Rona, with which Rasay is geologically continuous, I shall here content myself with barely mentioning that, in addition to those, it exhibits various alternations of hornblende schist and of the various compounds which have already so often fallen under review in describing the westernmost chain of islands. The red sandstone, commencing where the gneiss terminates, is disposed, as far as its boundary is con- cerned, in the same linear direction, with the exceptions already noticed ; that line being nearly N. by W. : but the nature of the ground, which often prevents the elevated edges from being seen, prevents also the con- tact from being ascertained. The direction of the strata follows that of the boundary, and appears, throughout the whole space occupied by this rock, to be N. by W., although in some places it seems to become occa- sionally N. and N.N.W.; variations, if they really exist, arising in all probability from those undulations to which strata are so often subject. It exhibits the same regularity on the western as on the eastern side of the island ; and. 244 RASAY. — GEOLOGY. •as there is no other method of reference, I must trust to the map to point out the space it occvipies. The dip is every where to the westward, but varies in the quantity of the angle. On the eastern side it is generally con- siderable, averaging perhaps 40°, while towards the west it becomes less, and in some cases subsides as low as to 10°. As the dip of the gneiss is towards the east where it lies near the sandstone, it is evident that they occupy reverse positions. Where the red sandstone terminates on the western shore it is followed by a white sandstone in a manner that will be described hereafter. Red sandstone occurs in two other places in Rasay ; and it is particularly interesting to trace these portions, as their positions, while they are somewhat obscure, are important, from the connexion which they establish between the northern tract just described and an exten- sive series of beds that will be shown to predominate in Scalpa and to occupy a large part of Sky as well as of the neighbourino; mainland. The first of these, as being the nearest to the main body, is a veiy small portion occupying a nameless point in the map ; its dimensions do not exceed a few hundred yards and it is accompanied by a portion of the usual conglomerate. The angle of elevation of the beds, of which the dip is also westerly, is scarcely 20°; and from that circumstance, as well as from the small quantity of the rock visible, it is difficult to ascertain truly the direc- tion, which however appears to be about N. by E. It is equally difficult to determine the true relative place of this portion of sandstone to the other strata, as it is separated by a chasm from the white sandstone that lies near it. If this be attempted by prolonging the planes of the beds, it seems rather to be continuous with than subjacent to that rock, but as it bears marks of disturbance, and as the white sandstone is occa- sionally irregular, that position may be considered as accidental. We are at least entitled by analogy to class IIASAY. — GEOLOGY. 245 this with the former red sandstone, as a portion of a hne extending round the east side of the island,, the remainder of which, to the southward, will be immediately described. In this respect it becomes interesting, as it might other- wise remain a doubt incapable of solution, whether the northern and southern red sandstone of Rasay were parts of the same deposit ; and, consequently, what relation the northern portion bore to the more distant rocks of the same nature to which I have already alluded. The extent and position of the last and southern division of this rock are also marked on the map, where it is seen lying opposite to the neighbouring shore of Scalpa. The line of direction here undergoes a change, becoming more easterly and appearing to lie about N. E. by E. ; although, from the imperfect manner in which it is displayed, this cannot be precisely ascertained. If it be as here stated, it approaches more nearly to the direction of the same rock on the shore of Scalpa, the line of bearing being there N. E. half E. Considering the proximity of these coasts, and the continuous extent of this rock to the southward, it is probable that, on both, it belongs to a common deposit ; and that these detached portions are connected by a regular succession of beds in those parts of the surface which are invisible by reason of the inter- vening sea. It must nevertheless be remarked, that while the dip of this sandstone in Rasay is uniformly towards the west, it varies in Scalpa ; a circumstance however which will not invalidate that conjecture, as in Sky, the same rock is subject to frequent and even sudden reversals of position. To extend the analogy between this southern portion of sandstone and the two already described, I may add, that, like these, it is immediately followed by the same strata of white sandstone. In recurring to the differences of direction of the strata in these three portions, it will be seen that they amount to six points of the compass, or upwards of 60°. If 246 RASAY. — GEOLOGY. therefore we consider them as detached parts of one set of beds, it is evident that these are incurvated in their course ; a circumstance not very unusual, since similar irregularities have been already pointed out in gneiss in various places, and vv'ill hereafter be shoAvn to occur among the strata of the Schistose islands. If this be a true representation of the position and connexion of the red sandstone in Rasay, its eastern shore, if suffi- ciently extended, would be surrounded with that rock, as I have already hinted ; * while, if a section adapted to the purpose could any where be discovered, it would be seen to pass under the white sandstone, which would thus be found contained within it on this side as in a basin. It equally follows, that it constitutes the upper part of a great deposit of red sandstone which reaches to the Kyles of Sky and the mainland ; bv;t I shall have occasion to discuss this question at more length hereafter. Having thus attempted to ascertain the geological history of this series, I must describe the particular sub- stances which belong to it ; having adopted the former general term, as on other occasions, to facilitate the de- scription, without meaning to confound different mineral substances under one name. At the points of contact with the gneiss there is found a very small portion of a conglomerate, which occurs in similar situations in Sutherland, in Ross-shire, and in Morven ; and which might have been enumerated with the varieties of the gneiss, since it is intimately connected with that rock. It is entirely formed of fragments of this substance, broken and reunited with very little change of character ; being of an equal degree of compactness, while, at the same time, it can scarcely be separated from the principal rock. It seems to be as partially distributed as it is small in quantity. In the same situ- ation there is found an equally small quantity of a finer * Sec the Maj>. IIASAY. GEOLOGY. 247 conglomerate, apparently as partial, formed of dark red felspar and hornblende schist equally mixed in distinct fragments, and producing, from the contrast of colour, a very peculiar appearance.* But the first conglomerate that forms a part of the sandstone beds, is found immediately above these ; pre- senting some detached and elevated rocks of a very remarkable character, on one of which is situated the very whimsical and picturesque structure, Brochel Castle, the ancient seat of Macleod of Rasay. This building is so contrived as to cover the whole summit of the sharp eminence on which it stands ; its w^alls being continuous with the precipitous faces of the rock. The projections of these have been so contrived as to form parts of the building ; and they are at the same time so like in appear- ance to the masonry of which it is constructed, that it is often difficult to distinguish between the artificial and the natural wall.f This rock is composed of the usual fragments that enter into the conglomerate in other places, but it appears to be very partial ; as in many parts of the line of junction the fine sandstone is found in immediate contact with the gneiss without any intervening substance. At the same time it bears no marks of stratification ; while its permanence, standing highly elevated as it does in pinnacles far above the surrounding rocks, shows, that with a texture apparently feeble and loose, it must possess much greater durability than the surrounding rocks, of the destruction of which it now remains a monument.^ * An extensive examination of the western shore of the mainland has since convinced rae that these conglomerates appertain to the red sandstone, as they occur in most places where the contact of that sub- stance with the gneiss can be fairly traced. — 1818. t Vide Plate II. ♦ The spiry form assumed by the conglomerate rocis on wasting is Ji very remarkable circumstance. I need scarcely remind the reader of Montserrat, and of the instances pointed out by Dr. Holland in Greece. 248 RASAV. GEOLOGY. The next rock which follows this and immediately pre- cedes the red sandstone near Brochel Castle, is a gray- wacke schist, forming a thin set of beds in very regular order and position, and easily examined on the sea shore throughout their whole extent. Higher in the hill, they are found in contact with the gneiss, but in other places they appear to be wanting ; or, if present, the quantity is so small that it is easily overlooked in a tract so covered with heath and bog. The substance here described is a fine graywacke slate, the laminse being separated by mica ; and it is remarkable for the number and regularity of the square and rhom- boidal fragments into which it breaks. Among the beds are found two or three containing small and large frag- ments of gneiss and quartz, cemented by the fine slate and graduating into it. This slaty conglomerate is irre- gularly disposed in alternation with the fine graywacke, and is separated by a wide interval of this substance from the conglomerate formerly described; with which it appears to have no connexion in structure more than in position. It may perhaps by some geologists be called a coarse graywacke ; but it differs in general character so widely from this substance, that I have preferred the use of the term conglomerate, for the purpose of avoiding the indistinctness and confusion that follow so lax a use of the former name. It is in itself a sufficient indication of the mechanical nature of the process by which the whole of the series connected with it was formed. The position of this mass of graywacke, intermediate between the first conglomerate of the sandstone series and the great body of that rock, would seem to indicate some anomaly peculiar to this spot; but it will here- after be seen in examining Sky, that it can only be viewed as an alternation of the graywacke and sandstone, innu- merable examples of which occur throughout the whole country. This rock is followed by the mass of red sandstone RASAY. — GEOLOGY. 249 that occupies the northern part of the island already- described. With respect to its structure, it wiU be suffi- cient to remark in general, that it consists in most cases of quartz sand cemented by red clay, with a small propor- tion of mica ; being obviously formed from disintegrated granite or gneiss. In a few instances the beds appear highly condensed and crystalline, being composed of quartz and red felspar intimately united; thus presenting a fur- ther illustration of their origin, the latter having in the progress of change become the red clay which forms the cementing medium in the predominant specimens. In terminating the history of this sandstone it may be remarked, that I have thought it unnecessary to specify the situations where a coarser gravel stone occurs, as it seems in all cases an accidental feature no way affecting the geological or mineral history of the rock. It happens occasionally in the progress of a single bed that the tex- ture will thus vary, while in other cases the change from fine to coarse takes place in irregular alternation. Varia- tions of colour are also here to be observed, and, like the changes of texture, they are sometimes lateral, sometimes alternate. They are not very uncommon in this rock and will be shown hereafter to exist in Sky in a very con- spicuous manner. If there are any other portions of red sandstone to be found in Rasay, a circumstance not improbable, as many scattered pieces of the uppermost strata are to be seen in different places, there will be no difficulty in referring them to the fundamental mass ; while the disturbance visible in some parts of the island will, together with the prevalence of overlying porphyry, be sufficient to account for their existence. Pecuhar circumstances in the disposition and structure of this island render it difficult to determine precisely the beds which lie next in order to the red sandstone but by combining analogy with observation they may perhaps be discovered. 250 RASAY. — GEOLOGY. At the northern part and on its eastern side, a culti- vated alluvial soil occupies the interval between the red sandstone and the white sandstone already mentioned which forms the great mass of the island. The inter- mediate substances, if there are any, are thus concealed from observation, and I may indeed add that the surface of the island in general is obscured by similar causes. At its southern extremity two circumstances unite to produce the same uncertainty, the vegetable soil in the interior, and, on the shore, the occurrence of a mass of porphyiy, occupying a considerable space and imme- diately following the red sandstone at the point where the connexion must take place. It is however here if any where that it must be sought. The strata which are here found near the porphyry consist of a dark bluish micaceous shale, alternating with a coarse limestone of the same colour containing much argillaceous earth, but, as far as I could observe, free from shells. Occasional fragments and indications of the eame substances are found in the interior of the island, even as high as the foot of Dun Can hill, but in a manner BO dispersed and in portions so minute, as to render it impossible to give them places in the map. To these rocks succeed white sandstone, here also interrupted and obscured by masses of porphyry ; but these being ab- stracted as interfering substances, the regular sequence will appear to be red sandstone, shale and limestone, white sandstone. If this conclusion should appear to be founded on insufficient data, it will be justified no less by general analogy than by a comparison with the series of rocks which occurs in the neighbouring islands, the description of which will appear hereafter. The sequence of the upper members of this series is to be seen in many parts of the eastern shore, where the same shale is found in the lowest position, immediately followed by the enormous accumulation of white sandstone which constitutes the high cliffs already described and 2 RASAY. GEOLOGY. 251 forms the bulk of" the island. Together with this shale, there are very thin beds of limestone ; very impure, inasmuch as they contain clay, sand, and mica, by which they are gradually confounded with it until they entirely disappear. The shale also, gradually losing its charac- ter, passes first into a schistose sandstone of an argillo- calcareous composition, and ultimately into the white sandstone. The organic remains found in the inferior strata of shale and limestone, are limited both in quantity and in variety ; but they are most abundant in the former rock, and increase in both respects as we follow the beds upwards. The lowest of these fossil substances are a gryphite, a pecten, and a terebratula ; the upper are far more numerous, and I shall here subjoin a list of them as far as it was possible to ascertain their characters from the specimens which I procured, often very mutilated and obscure.* It requires a fortunate concurrence of wind and weather to * Ammonitas. Pectines, some of them resembling those found near Bath and in Gloucestershire — others apparently unknown to all our conchologists. Terebratulce, smooth and subcvate ; also, plaited : neither of them definable. Ostreae ? — the resemblance considerable, though even the genus cannot be decidedly pronounced on. Chamae — fragments of shells apparently of this genus. Belemnitas. Gryphites. A Cardium ? Shells resembling the genus Corbula. Ossicula of a star fish or pentacrinites. An unknown shell with a general resemblance to Alcyonium. Fragments of bivalves resembling a Mya. A shell resembling the pecten concentrica of Oxfordshire, but longer- its genus not to be ascertained. Besides these there are numerous other fragments, but the whole are in so imperfect a state as to be incapable of examination, although they resemble generally those found in the lias of Somerset and Gloucester- shire. 252 RASAY. — GEOLOGY. obtain any access to these rocks, and it is seldom safe to remain long v/here the rising of the wind or sea may prevent the possibility of returning. In a gradation from the shale follow the great beds of sandstone, of which the exterior edges are exposed along the eastern shore, forming the great range of mural cliffs already mentioned. It is not possible to obtain any where such access to these beds as to discover by what gradations they change ; but while the whole series is strictly consecutive, slight variations are found in the detached parts, which seem to indicate that they become purer and whiter as they proceed upwards. The direction of the whole must be taken in a general sense as northerly, since it cannot be ac- curately determined ; and it is thus similar to that of the red sandstone on which it lies ; its dip, like that of the shale and limestone, being westerly, although no means are any where afforded of ascertaining the angle of inclination. By comparing the very moderate dip of these beds with the altitude of the cliffs, it will be seen that there is no great difference between that altitude and their collective thickness ; and as the former may be fairly estimated at 1000 feet, the depth of this mass of strata is evidently very great. The general character of the sandstone is argillo- calcareous. It is often of a yellowish colour, but oc- casionally of the purest white ; while towards the lower parts it is contaminated with blue clay, mica, and fragments of shale, containing also carbonized wood and a few of the organic remains already described. Large ammonitee are also found in it, but I did not procure any specimens so perfect as to enable me to ascertain the species ; if indeed it has been described by writers on conchology.* Portions of this rock are * The inadmissible expense of engravings adequate to the illustration of these and many similar subjects, must be an apology for their absence. RASAY. — GEOLOGY. 253 characterized by the presence of large balls, which are seen standing out on the faces of the. cliffs, or lying on the shore resisting the action of the weather long after the surrounding parts have decayed. These con- cretions are equally common in Sky and in Egg : they do not appear to differ in composition from the sur- rounding substance, but are too well known to geologists to require a detailed description. Large balls of trap occur also in the sandstone, but more rarely. The surfaces of these are always decomposed, and they bear evident marks of having undergone attrition before they were deposited in their present situations. Besides these different substances, there are found pedunculated ferruginous bodies resembling Pezizae, and doubtless ap- pertaining to the family of alcyonia. Before dismissing this rock I must take notice of an irregular portion which is seen on the western side of the island at the junction of the red sandstone. It is of small extent, but instead of lying on that rock in the usual conformable order, it is placed on its elevated edges and dips to the eastward of south, being, consequently, uncon- formable to the principal mass. Such appearances are not usual among the secondary strata, but, as the porphyry occurs here, it is probably an irregularity proceeding from the intrusion of that substance. I shall not attempt further to describe those portions which appear in various parts of the island, as if detached from the main body. This is often a fallacy arising from the intricate form of the ground and from the covering of vegetable soil : in some cases it is the result of the trap and porphyry, which either cover the uppermost beds or interfere with the whole by intersecting them. It is now necessary to take a short retrospect of the strata from the red sandstone upwards. The limestone which occurs at Broadford immediately on that rock, and will be amply described hereafter, contains the same organic remains that are found in the 254 RASAY. GEOLOGY. lowest shale and limestone of Rasay. It must be a subject for future inquiry whether that limestone is analogous to the mountain limestone of English geologists, or whether it be the lowest of the lias series. But there can be no doubt that the upper beds of this series in Rasay, the organic bodies of which have been recently described, belong to that formation ; although it rarely happens that the beds of lias are reduced to such a degree of tenuity. The sandstone which follows possesses a very marked character, and is known in other places to succeed or accompany these latter substances, exhibiting also the same gradations of composition which here take place at the point of transition between those two sets of beds. Were any other evidence of this succession required, it would be found in Sky; on the north-eastern shore of which island the whole series of the lias will hereafter be distinctly pointed out; and in such a position as to leave little doubt of its being a part of the formation of Rasay, sepa- rated only by the intervening sea. To that description I shall refer the reader for such further remarks as may be required, and proceed to consider the porphyry and trap, as the uppermost rocks occiirring in this island. As the sandstone is found occupying the eastern side of the southern division of Rasay, so the porphyiy is limited to the western, or to that part immediately opposed to Sky, where corresponding rocks are found in a similar situation occupying a considerable extent. It is equally remarkable that this porphyry is no where found among the gneiss, ceasing indeed before the red sandstone appears. The scattered and irregular position of this rock renders it impossible to define its boundaries, either by words or on the map. I have however distinguished it by a line, which may be taken as an average of its extent; marking those places where the most remarkable junctions with the secondary strata take place, as well as the size of the drawing permitted. UASAY. GEOLOGY. 255 In calling it the uppermost rock I have merely used this term because the principal mass lies above the sand- stone : it will be seen that it penetrates through that rock, as the analogous substances trap and syenite intersect the strata of Sky, and as similar rocks will hereafter be shown to do in many places. An instance of this fact is seen not far from the house of Clachan ; and again at a lower point on the shore, where it is also found lying over the sandstone ; while other similar examples occur further north on the western shore. It possesses there- fore, like the trap rocks, the double character of a vein and an overlying mass ; or that of a mass from which veins issue to penetrate and disturb the accompanying regular rocks. This porphyry presents no regularity of disposition, or at least no tendency to stratification. It has often indeed a foliated structure, resembling that which oc- curs in granite, but equally dissimilar to real stratifica- tion. Its general resemblance to granite is often very striking in other respects ; particularly in the rounded surfaces and piles of prismatic bodies which it displays ; while in some cases, assuming upright and rudely columnar forms, it cannot on a first view be distinguished from columnar trap. Although I have given the general term of poi-phyry to the whole mass, on account of the predominance of that substance, this rock does not exclusively occupy the whole space ; many portions consisting of that syenite which, equally with porphyry, is found associated with the ordinary trap rocks, and which forms by far the predominant part of that district of Sky which most resembles Rasay in character. These two rocks, formed of the same materials, and only differing in the arrange- ment of their parts, pass into each other by insensible degrees ; but as the syenite is far inferior both in quantity and variety, and will necessarily be described under the 256 RASAY. — GEOLOGY. head of Sky, I shall here limit myself to the description of the poi-phyry. Its basis is a compact felspar, most commonly of a very decided character, and rarely tending to that softer variety vi^hich passes into claystone, still less into the true claystone so abundant among the porphyritic rocks of Arran. The colom's being generally pale, the whole mass has a grey aspect;" and, containing much less iron than the syenite of Sky, it neither moulders so readily, nor have its fragments that rusty colour w^hich produces the arid appearance and red hue so charac- teristic of the syenite hills of that island. The colours of the basis are whitish grey passing to yellowish or brownish grey, and, by other shades, to greyish blue and to an obscure indigo tint. The imbedded felspar crystals are white or slightly yellow ; and thus, when interspersed in dark grounds, more particularly in the blue, produce occasionally a very ornamental stone. In decay, the crystals sometimes decompose first, leaving cavities filled with ochry clay ; the whole rock assuming a carious aspect. Small crystals of hornblende are sometimes contained in the base, together with crystals of quartz ; and these by their various proportions produce specimens of great variety of aspect. In the different junctions which I examined, no par- ticular change could be traced at the planes of contact, either in the sandstone or the porphyry : if there be any, it must be both slight and of rare occurrence. I must not conclude this description of the porphyry of Rasay, without pointing out the intimate connexion which subsists by means of it between this island and Sky ; the point of Aird Bhornis, which approaches within a mile or less of Clachan Point, being formed of the same rock.* * A sunk rock which lies in this narrow channel appears to be a prolongation of this point, and to be formed of the same substance. IIASAY. — GEOLOGY. ^57 Porphyry is not the only substance incumbent on the sandstone of Rasay. Different trap rocks are also to be seen, but they bear a very small proportion to the former. The most remarkable is that which forms the summit of Dun Can hill and a small area round it, risinsj many hundred feet above the highest part of that land which constitutes the mass of the island. It possesses the character of an ordinary basalt, but does not admit of our tracing any other connexion between it and the surrounding rocks than mere superiority of position. Its. mode of decomposition is remarkable, and, as in innumerable other instances, presents indications of an internal struc- ture which would not be suspected from examining the fresh fracture. It is contorted, as if originally consisting of fluid materials of different densities which had been disturbed previously to their consolidation. The only other trap rocks which I examined are found on the western shore not far from Clachan. In com- position they are peculiar but not solitary, as other similar compounds will be described hereafter, and they tally precisely with a rock that occurs at Balmeanach on the opposite shore of Sky. The basis is a mixture of augit and felspar, a rock which will be amply described in As it is very dangerous to mariners, and is not found in Mackenzie's chart, its bearings are here laid down ; — The point of Camistianevig hill N. by E. |: E. Clachan point S.E. by S. Aini Bhornis point S.W. by S. A small rock visible near the Sky shore W. by S. There are twenty feet of water on it at spring tides, and it breaks at low water only when the sea is running high from the north. I have on many occasions pointed out errors in the work above mentioned, not because it is faulty, but because it is valuable, while it is the only one to which the navigator of the Western isles can trust. In the anchorages, soundings, and tides, it is generally accurate. Were some omissions in the harbours and sunk rocks supplied, and the general outline (a matter systematically neglected) rectified, it would l)e sufficiently perfect. VOL. I. S i258 RASAY. GEOLOGY. another part of this work, and which I have distinguished by the name of augit rock, to separate it from the common greenstones with which it has often been confounded. It contains, in addition to these ingredients, prehnite ; sometimes dispersed in small globular concretions so as to form a constituent part of the rock, in other cases distinctly placed in cavities and imperfectly crystallized. This prehnite is most commonly of a white colour, rarely inclining to very pale green. I discovered no other independent mineral in Rasay. Veins of trap occupying the usual positions occur in different parts of the island, but more rarely than would be expected, when we consider their abundance in Sky, and the vicinity of the great masses of trap in that island, in the neighbourhood of which they are commonly so predominant. They seemed no where to present any appearances sufficiently remarkable to be worthy of record. FLODDA. GF.NEUAL DESCRIPTION. 259 FLODDA. This small island would scarcely have had any claim to be noticed, had it not, from the greater simplicity of its structure and from affording more perfect access to its rocks, served to illustrate some points in Rasay which are not quite satisfactory, and concerning which it was necessary to add analogy to observation. Its history will also in some measure prove an introduction to that of Sky, while, by increasing the number of examples, it will show that the instances of peculiarity there to be described are not solitary. The connexion of the graywacke schist with the sand- stone is but imperfectly seen in Rasay, and for a small space ; but in this little island it is displayed in great perfection. In Rasay also there is some difficulty in making the boundaiy of the gneiss coincide with the line of direction of the sandstone strata ; while, the latter being perfectly straight and no rock but a small portion of conglomerate intervening between the two, there ought to be a perfect coincidence. The cause of this will immediately appear in describing Flodda, and I have attempted in laying down the coast to show the nature of the interruption, which arises from the intrusion of the gneiss beyond the line it might have been expected to occupy.* This island appears to be about two miles in length and half a mile in breadth, presenting a nearly flat surface, elevated, at the utmost, fifty feet above the level of the sea. It is separated from Rasay by a narrow strait, incorrectly laid down in Mackenzie's chart, since it is dry- in the middle at half tide and affords a communication between the two islands. It is surrounded by several * See the Map of Sky anil the adjoining islands. 250 FLODDA. GEOLOGY. rocky islets, all resembling it in composition. There is a perfect natural section on the side next to Rasay by which its structure is completely displayed. '' The whole island is formed of the graywacke schist and red sandstone already described as found near Brochel Castle, the former however bearing a very con- spicuous proportion to the latter. As it is similar to this part of Rasay in composition, so it corresponds in the incUnatioil and direction of the strata; but the angle of elevation is lower and does not seem to exceed ten degrees, while in some places it is as low as five. As the direction of the strata is similar in both the islands, and the position of the sandstone in Rasay is regular, it might have been expected that by prolonging the outer line of the latter, the whole mass of sandstone in both would have been determined by a rectilinear boundary. This however is not the case, since the point of gneiss already mentioned protrudes across the line which should have been here uninterrupted. It is not difficult to comprehend the cause of this, if we advert to the proba- bility that the sandstone was deposited on an uneven sur- face of gneiss, and that, the section parallel to the horizon, produced by the ordinary wearing of the surface, would consequently leave a protuberant mass of this rock trespassing beyond its linear boundary. The same effect would follov/ if we conceive the gneiss to have been elevated after the deposition of the sandstone. This circumstance will explain the irregularities that take place in Rasay at the common boundary of these rocks, which I forbore to notice in describing that island, because the appearance was neither explicit nor the cause obvious. The graywacke that lies under the sandstone, forms a series of beds with a schistose fracture parallel to their planes of stratification, being immediately followed by that rock, without any intermediate conglomerate as in Rasay. I did not here observe it alternating with the sandstone ; which is nevertheless to be expected, FLODDA. — GEOLOGY. 26l since in Sky and the neighbouring islands it occurs in this manner. It is of a fine and smooth texture, sometimes not to be distinguished from clay slate, except by the rare scales of mica which are found at the separation of the laminae. There is nothing in the character of the red sandstone so different from that of Rasay as to require notice. The alternation of those two rocks where they occur in these islands, and their regular sequence in this, show that, in a geological view, they are both parts of the same series. 26s SKY. GENERAL DESCRIPTION. SKY.* If the magnitude of Sky were not a sufficient apology for the space which its description occupies, an excuse will be found in the variety and intricacy of the rocks of which it is composed, as well as in the unexpected nature of their connexions. Such appearances do not admit of being detailed with the same brevity as those which, from their correspondence with prevailing phe- nomena, are capable of being referred to a numerous class of analogies. As nothing but a minute examination could have satisfied the doubts of the observer, so a correspond- ing description is necessary to remove or anticipate those of the reader. I have nevertheless rescinded all such observations as appeared, in this view^, superfluous ; while, their topographic importance being trifling, their absence will in that respect be immaterial. The dispersed manner in which many of the rocks geologically connected are here situated, has also neces- sarily led to some difFuseness; perhaps to some repetition: while the importance of many of the facts has frequently compelled me to enter into general statements, which, should they appear superfluous to some, seemed absolutely required for the purpose of connecting the phenomena in an intelligible manner ; as well as for the elucidation * Sky, clouds, Scaiid. The Tsle of mist of the Gaelic poet. The Highlanders, who look no further than their own language, derive it from Skianach, winged : an etymology unworthy of a comment. — See the Map of Sky. A paper on this subject appeared in the 3d Vol. of the Geol. Trans. : of a partial nature, but corrected and enlarged by subsequent remarks. The importance of the subject has induced me to remodel the whole : with the advantage of a more intimate knowledge of the country, and on a plan consistent with that adopted respecting the other islands described in this work. SKY. — GENERAL DESCRIPTION. ^65 of some prominent and unsettled points in geological science. The extreme length of the island appears to be about forty-five miles, and that line, lying between Vaternish point and the point of Sleat, is not materially different from a mean length of its sides, considering it as a parallelogram. Its extreme breadth lies between Cop- nahow point and Ru na braddan, and may be taken at twenty-four miles ; but a more correct general idea of its superficial dimensions will be fonned by measuring nearly across the middle of the island, which will give a mean breadth of fifteen. The superficial content does not how- ever correspond to these measurements, in consequence of the remarkable indentations of the coast ; the sea entering on all sides in such a manner, that it is difficult to find a place five miles distant from the shore. Its boundary is almost every where rocky and elevated ; often rising into cliffs of great altitude, no less remark- able for their picturesque forms than valuable to the geologist for the display which they afford of the interior structure of the island. The surface of Sky is almost invariably hilly, pre- senting three distinct assemblages of mountains separated by intervening tracts of high and undulating land : the plain of Kilmuir and a small tract near Loch Bracadale are the only exceptions. As these differences of exterior character are generally accompanied by changes of the component rocks, I shall, in describing the several divisions, slightly notice the prevailing substances, pre- paratory to the more minute details into which it will afterwards be necessary to enter. Commencing with the southern division, a continuous ridge is found extending from the point of Sleat to Loch in Daal, where it suddenly subsides into a low tract stretching northwards towards Broadford. The general elevation of this ridge may be estimated at twelve hundred feet, or more ; and it may be considered as continuous 354 SKY. — GENERAL DESCRIPTION. in the centre ; being nevertheless irregular, and containing sinuosities, rather than valleys, which conduct its waters in small streams into the sea on each side. Almost the only wood that grows on the island is found in this district ; the ash flourishing on both declivities of the promontory wherever the course of a stream through some small valley or ravine affords it shelter; and occu- pying, together with birch and alder, (the trees most congenial to these islands,) larger tracts on the western side near Ord, where the perishing remains of a wood once considerable are to be seen. The flat tract above mentioned, into which the ridge of Sleat subsides, extends but for a short space in the same direction, which is north-easterly ; rising again quickly into a second and more elevated ridge consisting of five united mountains ; and thus intersecting the otherwise continuous high land of the south-eastern shore, by one deep indentation. On the eastern sides, these mountains descend by rapid declivities into the sea ; while, on the western, they subside more gently into a low and narrow tract that extends from Broadford to Kylehaken. The elevation of this group does not appear to fall short of 2000 feet, and it is conspicuous among the hills of Sky, not less from its actual height and mass, than from the low tract by which it is insulated from the surrounding country. Notwithstanding the inter- ruption here mentioned, these hills must be considered as forming a part of the ridge of Sleat, since their com- ponent rocks are not only similar, but are disposed with an unaltered continuity of direction. The prevailing rocks of the whole ridge from the point of Sleat to the Kyle rich,* are, red sandstone, argillaceous schist, and quartz rock, accompanied by a body of gneiss and by other substances of which the details must be referred to the geological description. * The swift strait — a very expressive term: incorrectly, though gene- rally, Kyle lea. . SKY. — GENERAL DESCRIPTION. 265 The ridge tnus described is separated from tlie next elevated land to the north-west, by an irregular low tract forming a valley parallel to it and extending from the head of Loch Eishort towards the northern shore between Kylehaken and Broadford, A second irregular ridge succeeds to this, occupying the whole space from Swish- nish point to Broadford and beyond it ; and followed by another parallel valley, that of Strath, but little elevated above the two seas which it here separates. With some interference from syenite, the whole valley of Strath consists of limestone, the peculiarities of which, like those of the rocks before mentioned, must be referred to the geological description. Thus far. Sky is found to consist of regular stratified rocks, which, whether primary or secondary, are extended in a line of which the prevailing tendency is north-east. But here all regidarity ceases, and although some de- tached portions of the same and of other strata are to be found in several places, the remaining mass of the island must be considered as formed of unstratified rocks ; all belonging to the family of trap, (including under that term syenite,) and, though of various external forms and characters, all incumbent on the strata and of posterior date. With the regularity of the rocks, that of the hills and valleys ceases ; although there remain certain leading features to facilitate the division and description of the remaining tracts. The most conspicuous part of the island is that which follows next from Strath to the northward, and consists of a confused assemblage of mountains of diflerent ex- ternal features, definable by two irregular lines drawn from the head of Loch Slapin to near Broadford on one side, and from Loch Brittle to Loch Sligachan on the other. There is no measurement of the height of any individual of this group ; and unfortunately the general state of the weather in this stormy island has hitherto ^66 SKY. GENERAL DESCRIPTION. prevented me from supplying that defect.* An estimate must for the present be substituted ; and it will not be far from the truth if the altitude be taken as ranging from 2000 to 3000 feet ; the lowest apparently not falling short of the former, and the highest probably not exceed- ing the latter elevation. As the names of the principal hills appear in the map, it is mmecessary to enumerate them, unless where the circumstances occurring in any individual require particular notice, since they are all asso- ciated by two or three leading characters. This group is divided into two portions, intimately united, yet characterized by striking differences in their external outlines and general features ; circumstances arising from differences of composition, although both divisions equally appertain to the trap family. These external features are accompanied by a remarkable differ- ence of colour, which, together with the strong contrast of their respective outlines, forcibly attracts the attention of a spectator on arriving in this island. By far the larger portion presents a set of tame and generally rounded outlines, particularly unpleasing to the eye ; the hills that form it being all separated from each other, and all equally characterized by the smooth and blunt conoidal shape ; not a single projection appearing to break the uniform line they make on the sky, and their surfaces being equally devoid of the variety arising from bold crags or deep recesses. To add to the generally unpleasing effect, they often arise at once from the low grounds, * When tlie reader is told that I made seven attempts and in five successive summers to ascend the Cuchullin hills, he will form some notion of the nature of the climate and will perhaps receive this as a sufficient apology. Sky is however exempt from the duraljle snows which during the winter cover the adjoining mainland. Asking a young female who was weeding some wretched potatoes in Loch Ilourn, wiien the snow dissolved, the answer was " It never gangs till the rain conies'' -^sucij is the alternative. SKY. GENERAL DESCRIPTION'. 267 without that variety of gradation and of compUcated sub- sidence into lower ranges, which, even in liills of tame outhnes, often produce forms not deficient in beauty. The cause of the pecuharities now described is to be found in the facihty with which they are disintegrated by atmospheric action, whence their outhnes necessarily assume these characters ; while the loose stones, by their constant descent from the summits, obscure the rocky surface, covering the sides with long torrents of red rub- bish even more unpleasing to the sight than their conoidal forms. That red colour is indeed one of the most striking features of these hills, and although not universally pre- valent among them, it occupies by far the larger space ; while its superior conspicuity increases its apparent extent. It will hereafter be seen, that this effect arises from the syenite of which these hills are principally composed, which, on decomposition, suffering the pyrites it contains to rust, acquires the colour in question; while the frequent re- newal of the fallen materials prevents the accumulation of vegetable soil or covering. To distinguish this part of the group, I shall give them the general title of the Red hills, as it will often be necessary to speak of them collectively ; while they are, by this circumstance, as strongly as by their outline, contrasted with the other portion, the colour of which is dark. The darkness of that mass is indeed extraordinary, and adds much to the wildness of aspect and grandeur of effect produced by the rugged and bold outlines of the moun- tains of which it is formed. No light seems to harmonize their colour to its place in the general landscape : per- petual shadow appears to cover them in every state of the atmosphere, and when the clouds involve their sum- mits, a deep and dark abyss seems opened beneath into which the eye vainly endeavours to penetrate. Their exterior outline is equally remarkable, as well for the contrast it presents to the tame and smooth boundary of the Red hills, as for its peculiarly rugged and serrated 268 SKY. GENERAL DESCRIPTION. form. Pinnacles and projecting crags darkly indenting the sky rise along the whole line, marking by their acute- ness and permanence the durability of the rock of which they are composed, and indicating to the mineralogist a difference of composition between these and the neigh- bouring mountains which on a nearer examination he finds actually to exist. These differences will be the subjects of future discussion, but I may add that nothing more forcibly strikes the spectator in contemplating these mountains than this unequal durability of the two por- tions into which they are thus divided. ■ The chief part of the dark group consists of the Cu- cliullin hills. These form a curved ridge, rising from the shores of Loch Brittle and the sound of Soa with a rapid and rocky ascent ; being obscurely divided into six summits, and the whole terminating towards the east in an almost con- tinued precipitous face deeply furrowed by torrents. Some lower, but equally rocky hills, of similar composition and character, unite with them to enclose the lake Coruisk ; Avhile Blaven, forming a long acute ridge in a position still more easterly, rises above the whole ; constituting the highest mountain in the island, and completing, with its bare and rocky surface, this dark and rugged mass. To the northward of this grouj), on the western side of the island, the land continues high and hilly, but is no longer mountainous ; its general elevation lying between 600 and 1000 feet, and its undulating surface being almost every where covered by brown heath, so as to present a dreaiy iminteresting appearance. The green pastures of Loch Brittle and Loch Eynort, the little valley of Talisker, and the low, open, and cultivated tract of Braca- dale, form the only considerable exceptions to this general character. I may however add that the promontory to the west of Dunvegan appears to rise into hills somewhat higher than the general elevations above mentioned ; the two flat topped eminences called Macleod's tables being- conspicuous at H distance, not less from their resem- SKY. GENERAL DESCKIPTIOX. 2(59 blance to each other, than from the pecuharity of their outhnes. There is httle throughout all this range of the in- terior country to attract the attention of the painter. If the distant outhne is often grand or picturesque, the want of objects in the middle ground leaves the landscape barren, naked, and meagre : the artist searches in vain amid the w^earisome repetition of brown, smooth, undu- lating moor, for the dark wood, the bushy ravine, the rocky torrent, or the intricacy of broken hills, to con- trast with the distance and to fill his picture. The beautiful columnar range of great Brishmeal, above Tuhsker, is almost the only object throughout the whole tract capable of soliciting his attention. The general character now given is that of the whole country as far as the line that joins Portree to Loch Snizort; a tract as uninteresting to the geologist as to the painter, since it presents him nothing but a perpetual recurrence of trap rocks in their most common forms. The north-eastern portion of the island, comprising the district of Trotternish, offers more variety and interest. A long ridge, commencing at Portree, stretches away to the point of Aird ; being elevated towards the middle into mountainous eminences, which, rising by a gradual accli-- vity from the west, terminate to the eastward in a rapid, descent; often displaying precipitous faces of great extent, attended by circumstances of considerable grandeur and picturesque beauty. The greatest altitude of this ridge may be estimated at 2000 feet, and the highest point, the Storr, is at the same time the most picturesque. Here, the summit of the mountain is cut down in a ver- tical face, four or five hundred feet in height; while the steep declivity below is covered with huge masses of detached rock, the more durable remains of the cliffs above, now separated from that precipice of which they once formed a part. These are combined in a variety of 270 SKY. — GENERAL. DESCRIPTION. intricate groups ; while their massy bulk and their squared and pinnacled outlines present vague forms of castles and towers ; resembling, when dimly seen through the driving clouds, the combinations of an ideal and supernatural architecture. The most remarkable of these rocks is said to be 160 feet in height, and, with the form, it emulates at a distance the aspect of a spire, presenting from afar a sea-mark well known to mariners.* The remainder of this ridge exhibits other abrupt faces of rock not void of picturesque effect, but so much resembling in general character the more interesting shore scenery in which the island abounds, that it is unnecessary to describe them. Near Duntulm however, as well as towards Loch Staffin, the rocks assume the columnar disposition ; and their long ranges, here rising above each other in distant succession, combined with the masses of hill which they crown, produce scenes of great variety and of powerful effect, if not strictly ame- nable to the rules of picturesque composition. On the western side of Trotternish the plain of Kilmuir presents the largest continuous tract of arable ground in Sky, emphatically called the granary of the island ; while the deep indentation of Loch Uig, surrounded by a double line of cottages rising in two tiers upwards from the sea, each with its equal allotment of land, affords one of the most singular spectacles in rural economy, that of a city of farms. As it is chiefly on the long extended and sinuous shores of this island that the geologist will find those details in which he is most interested, so it is there that the admirer of picturesque beauty will meet with the most frequent subjects of his pursuit. For both these reasons * Had this rock been in the plains of Ilindostan instead of the moun- tains of Sky it would have been an object of greater devotion than the Jaggernaut Pagoda. The Gaelic name of this Lingani does not admit of translation. See the plate. SKY. — SPAR CAVE. f^7 I I shall now therefore trace the line of" the coast, of which the leading features would otherwise be passed over in silence ; since, through a large space, the identical nature of the rocks will prevent any description of them from being required in the geological investigation. The promontory of Strathaird, from which this descrip- tion commences, is low at its extremity, being there formed of those stratified rocks which constitute a portion of the adjoining shores of Loch Eishort, but it rises gradually towards Blaven by a succession of hills of trap presenting no remarkable features. It is for the most part surrounded by cliffs, rarely exceeding sixty or seventy feet in height, and cut smoothly down so as to afford a perfect display of the succession of the strata of which they are composed. On the eastern side these are remarkable for the very extra- ordinary number of caves they contain, and for the fissures by which they are intersected. These are rarely of any great dimensions, but are so numerous that they some- times occupy nearly as much space in a given distance as the solid parts of the cliffs themselves. Twenty or thirty are sometimes found in the course of a few hundred yards, the interstices having a resemblance to tlie ends of detached walls placed in a parallel manner. They are the consequences of trap veins which have been washed away, but as they present important geological facts, they will be described more particularly hereafter. Few of these caves have been explored, but one has acquired historic celebrity from its having been among the numerous places of temporary refuge inhabited by Prince Charles during his concealment. Another has recently be-^ come the cause of great resort to Sky on account of its sta- lactitic concretions, being popularly distinguished by the name of the Spar Cave : it lies on the estate of Mr. Maca- lister, and is too well known to require any more accurate description of its locality. This cave is accessible from the cliffs above, for a short time only, at low water ; but by means of a boat it may be visited at any time ia 372 SKY."— SPAR CAVE. moderate weather, or with the wind off the shore. The entrance is little less striking than the interior, and to the admirer of the picturesque it presents a scene even more attractive. This is formed by a fissure in the clilF, extending for a considerable way and bounded on each side by high and parallel walls, its gloom being partially illuminated by reflected light, and its silence scarcely dis- turbed by the wash of the surf without. A narrow and obstructed opening leads unexpectedly into the cave, which for a distance of about an hundred feet is dark, wet, and dreary. A steep acclivity formed of a white stalagmite then occurs, which being surmounted with some difficulty, the whole interior comes into view, covered with stalactites disposed in all tlie grotesque forms which these incrustations so commonly assume. Lively imaginations may here indulge in the discovery of fanciful resem- blances, and the concretions have accordingly received names more descriptive of the fancies of the spectators than of their real forms. The dimensions of the fissure are in this place but inconsiderable, the breadth not being more than ten feet, and the height scarcely exceeding twelve. Here however the latter suddenly rises to forty feet or more, the surface of the stalagmitic and cascade- like mount which divides the sparry from the dark part of the fissure, conducting by a declivity of about thirty feet in length, to a pool of water that occupies a space of twelve or fifteen feet, and divides the whole into an outer and inner portion. The dimensions are here somewhat enlarged, and the height in particular becomes much more considerable. At a distance of about fifteen or twenty feet more from the pool, the stalactitical ornaments cease, and shortly after the cave terminates ; the whole length from the entrance to the extremity being about two hun- dred and fifty feet. However beautiful the interior of this cave may be, from the white colour and ornamental effect of the stalactites which incrust it, the want of sufficient dimensions materially lessens the interest which in all <;KV. SPAR CAVE. 273 Other respects it is calculated to excite. At the termi- nation of the stalactitical ornaments there is a dark descent for a few yards, filled with rubbish from the ruins of the roof above, which being here naked as well as accessible, is plainly seen to be one of the trap veins. This vein is here about ten feet wide, which is the general breadth of the cave itself, and it is easy to see how by the wearing out of its substance the excavation has been foi-med, having subsequently acquired its present degree of orna- ment by the infiltration of carbonate of lime. Considering the great depth of this cave and its present distance from the sea, we are inclined to inquire by what means so extensive an excavation could have been formed, and how the rock which has fallen from it has been removed.. It is probable that the depth of water at the face of the cliffs was once such as to permit the ready access of the sea to them, and that at this period the excavations so numerous on this shore were pro- duced. The subsequent accumulation of rubbish formed by its action, has in later times produced the slope or shore which now excludes it from further access and protects the cliffs from further demolition. In the excavations which are found in the floor of this cave we have the means of seeing the process by which calcareous spar is forined, the crystallization being carried on in a solution of the carbonate of lime, precisely as it is in the saline solutions in our laboratories. All these small pools are filled with groups of crystals, in a state of constant augmentation, and all of them, however accumulated, displaying the primitive rhomb. Doubtless, these forms must be affected by the agitation which the falling drops occasion in the solution; and it is in all probability owing to some circumstances of this nature, constant in the same spot but varying in different situations, that crystals of one form are found to affect certain places, while in others they regularly assume some other VOL. I. T 274 SKY. COAST SCENERY. modification. As this cave offers no other novelty to the mineralogist, and belongs to a class of geological facts by no means uncommon, it is unnecessary to enter into any further details respecting it. If we except the gloomy solitude of the mountain sceneiy at the head of Loch Slapin, the coast can scarcely be said to present any interest either throughout the remainder of this inlet or the adjoining one of Loch Eishort ; the land descending almost every where without cliffs to the sea, and, except about Ord and Dunscaich, being scarcely varied by the adventitious circumstances of scattered wood or ornamental cultivation. From these points the distant views towards the north-west are never- theless grand and striking, including the wide expanse of the sea, bounded on one side by the contrasted fonns of the Sky mountains, and on the other by the more distant hills of. Rum. There is but little interest or beauty during the remain- ing part of the circuit round Sleat till we arrive at the narrow sound that separates it from Glen Elg, if we except the prospect of the opposite shore, formed by the wild and lofty mountains of Loch Hourn and Loch Nevish. The land in this strait rises high, and generally with a rapid acclivity, displaying broken rocks interspersed with coppices and brushwood and enlivened by innumerable torrents, which together with the proximity of the sides, the rapidity of the tide, and the quick succession of objects, all conspire to excite an interest which is preserved till we arrive at the wide bay that forms the entrance of Loch Duich. Here, the variety of the coast line, the wide but intricate expanse of water, the scattered rocks, the picturesque and various out- lines of the mountains of Sky itself and of (he mainland, with the ruins of Kylehaken Castle, its rising town, and the bustle of the shipping that frequents this sea, combine to produce scenery scarcely exceeded on the western coast. But here again all beauty once more vanishes SKY. — ^ COAST SCENERY. 2/5 as the open channel appears, besprinkled it is true by- islands and backed by mountains, but the former being withiut intricacy as the latter are without grandeur. The character of the coast continues equally unin- teresting to Portree, but from this place northwards to Loch Staffin a long and almost unindented line of shore extends, unlike the greater part of the island, since it offers no refuge for ships ; not even a cove or a flat shore existing where a boat can be drawn up. At a distance, the whole line presents an uninterrupted wall of high cliffs rising in successive stages above each other ; the mural face of each being surmounted by a green terrace, sometimes terminating in the sea, at others skirted by a slope of huge fragments interspersed with verdure. On a nearer examination a greater variety is found; the high cliffs, which appeared to overhang the water, often retiring into the interior, while the nearest present more moderate elevations, and in one or two places disappear altogether ; a gentle descent leading down from the interior precipices to its edge. The high and rugged summit of the Storr, with its lofty precipitous face and the pyramids which cover its declivity, towers above all ; giving the central feature and leading character to the whole scene and stretching away into the long ridge of mountain land that cro^vns this line of rock. In general the high cliffs of this shore present such a continued uniformity of character, that the impression of grandeur and simplicity produced by the first aspect of their continuous, even, and lofty, faces, is lost by frequent repetition ; the high cascade of Holme being almost the only feature to vary the scene between Por- tree and Ru na braddan. Beyond this point a series of columnar cUffs commences, stretching away to Loch Staffin and presenting the general features of the ranges of Staffa, but on a scale of five or six times the mag- nitude. Although the columns are not so accurately formed nor so distinctly marked as in that island, their £76 SKY. — COAST SCENERY. effect at the proper point of sight is equally regular; while from the frequent occurrence of groups, recesses, and projecting masses, and from the absence of any super- incumbent load, they are far superior in lightness of appearance as well as in elegance and variety of outline. In many cases, where the columnar trap lies above the horizontal strata, the appearance of architectural imitation is much more perfect than in any part of StafFa; the stratified rocks presenting horizontal courses of natural masonry, resembling basements, crowned by straight or curved colonnades ; one of which, from a particular point of view, so exactly represents the general proportions and character of a circular temple of Greek architecture, that the artist who should represent it truly would be suspected of forcing nature into the forms established by art. A sino'ular circumstance sometimes occurs amono^ these columnar ranges, adding much to the lightness and elegance of their effect. This is the detached state in which slender groups or single pillars remain after the surrounding parts have fallen away. From this mode of wasting, the summits of the cliffs are sometimes crowned with pinnacles, or with conoidal points resembling those of the latest style of Gothic architecture : while in a few instances, single columns or groups are seen standing detached before the colonnade as if they were the last remains of some ruined portico. One of the most remark- able appears to be about 200 feet in height ; its lower part being clustered, and the pillars terminating in suc- cession upwards till a single one remains standing alone for a height of thirty or forty feet, and apparently not above four or five in diameter. In another place a group of five or six, adhering together laterally, stands advanced in face of the chff, presenting its narrowest edge against the sky and reaching -to fifty or sixty feet in height. A similar detached column, but of far less height, is seen in the small island of Trodda, and another of still inferior dimensions on the shore to the south of Duntulm Castle. SKY. — COAST SCEXEKV. 2// At Loch Staffiii the hills m the interior rise with great magnificence to the height of 1000 and of 1500 feet, en- closing a large sweeping valley. The long columnar ranges already mentioned which crown their summits, in- creasing in elevation as they retire in succession, assist with the cliffs below that present the same regularity, in pro- ducing a variety of scenery to which that of all the basaltic islands must yield in magnificence and extent, however it may sometimes exceed in simplicity and grandeur of effect. I must not, in quitting this shore, omit to notice a second cascade which, if not of equal magnitude with that of Holme, is still very striking from the simple and unbroken manner in which it falls over a columnar and vertical cliff not less than 300 feet in height. There can be nothing picturesque in such a disposition of parts, but there is an effect produced by the total absence of all accompaniments v.?hicli from its novelty and simplicity is very striking. When the squalls, which blow from the high lands in this stormy region, descend so that the sea rises in smoke beneath them like the vapour from a cauldron, but little of this stream reaches the waves below. The columnar forms continue for some way round the point of Aird into Loch Snizort, where the ruins of Duntulm Castle serve to give interest to dimensions now far contracted in altitude and in extent of sweep. But at a point not far to the southward of that ruin, is a small promontory presenting a resemblance to some parts of StafFa, and on a scale sufficient for grandeur, to an eye not previously satiated with the overpowering vast- ness of the eastern coast. Had StafFa remained unknown, this spot might have acquired the celebrity which has been exclusively reserved for that beautiful yet not sin- gular display of columnar scenery. It will be rendering an acceptable service to the admirers of that island to point out an object hitherto unknown, which, with some variety of disposition and effect, is not unworthy to rank 278 SKY. COAST SCENERY. with it among the attractive scenes of these interesting shores. Three caves occupy the front of this pro- montory, being formed, Hke those of the large cave of Staffa, among the cohimns ; and presenting, although on a smaller scale, the same general effect of architectural order. A sharp contrary sea, produced by the stream of tide running round the point, prevented me from entering them ; an attempt to be made only in smooth water and fine weather; I cannot therefore give any account of their interior dimensions or arrangement. Their height appeared to the eye to range from fifteen feet to thirty, the highest being the most northerly, and the total height of the promontory being about sixty feet.* Beyond this point occur the rich flattish tract and the low shores of Kilmuir, no further objects of interest appearing along the remaining coast of Trotternish, if we except Loch Uig, formerly mentioned. The shores of Vaternish on both sides appear to be equally void of interest, consisting of a succession of vertical cliffs alternating with occasional low shores, and productive of scenery which, however striking on a first view or when occurring sparingly, becomes mo- notonous from its identity and tix'esome from its repetition. I must not however pass Loch Follart without pointing- out the beauty of the views over its wide expanse sprinkled with islands ; enhanced by the interest derived from the picturesque aspect of Dunvegan Castle.'f- The coast from Dunvegan head to Loch Brittle is, with few exceptions, formed of high cliffs ; variable in their altitudes as in their abruptness, but generally very lofty; often indeed precipitous and even perpen- dicular from their summits to the water's edge. Between that promontory and Loch Bracadale they are often also perpendicular, but variable in height, seldom '» Flale IV. t Plate SKY. — COAST SCENERY. 279 -attaining the great elevation which they reach between Tahsker and Loch Eynort. They often present a sin- gularly striped appearance, from the great variety of colours in the several beds which compose them; of which twelve or more may in different places be counted, all horizontal and tolerably equal in their dimensions. The forms of these cliffs are far too monotonous and too square to afford subjects for the pencil, every part being marked by a general similarity of character. Near the entrance of Loch Bracadale some variety is pre- sented by the three detached and pyramidal rocka called Macleod's Maidens, the highest of which appears to reach to about 200 feet.* Such detached pyramidal masses are of frequent occurrence on this coast, a re- markable perforated one being seen in Loch Bracadale, and a similar one not far from Loch Eynort. They are, like all other objects out of the ordinary course of nature, rather singular than picturesque : the strange and the bizarre are seldom legitimate subjects for painting, and rarely please long, after the first v/onder has subsided. Some caves are found in Loch Bracadale but they have no particular claims on notice, either from their beauty, their magnitude, or their singularity. Similar caves are of frequent occurrence between Talisker and Loch Brittle, the low projecting rocks being also often per- forated by arches which are sometimes exceedingly complicated and remarkable. With the exception of some projecting points of high rock, the shores of Loch Bracadale are flat, this tract being also one of the most fertile spots in Sky. At its southern extremity the cliffs are perfectly vertical, and without that slope at the foot which so commonly accompanies the high cliffs of trap and are so conspicuous in some places on the eastern side of the island. The retired and green valley of Talisker opens to the sea by a low beach, on which * Plate III. 280 SKY. COAST SCKXEIiY. a natural embankment has been formed by the westera swelL Here the difts again become high, and shortly rise to the greatest altitude which they attain along the whole line of this coast. In a general sense they may be called perpendicular, but they are seldom without grassy slopes, either at their feet or in some intermediate parts, which diminish their vertical appearance when seen in profile, although v/hen viewed in front they still appear perpendicular. The outline is here more varied, the parts more numerous and intricate, and the tones of colour more agreeable ; while the foregrounds, which are formed by some high and conspicuous detached rocks, assist in producing some of the most magnificent compositions of rock scenery that are to be seen on the coasts of Sky. Not far from this place is a large and very remarkable slide, by which a considerable portion of the cliff has been brought from the summit down to the shore, where it forms a promontory ob- structing the further progress of the mineralogist who in defiance of toil and hazard pursues along this rocky coast the beautiful minerals in which it abounds. The heights of these chffs are considerable. Comparing them with the masts of passing ships they do not seem to be much less than 800 feet. The cascades which fall over them are often dissipated in spray before they reach the ground, or descend in a shower of drizzling rain. The cliffs continue with more vaiiety of height than ' of character to Loch Brittle, the habitation of the Osprey, and of some rare minerals more interestino- to geolog-ists. At this Loch the land runs out into low projecting points, the interior being of small elevation and disposed in terraces. The cliffs rise but little from this place to the entrance of Loch Scavig, where the coast assumes a new character, the declivities of the hills reaching the sea at a considerable angle, and without intervening cliffs. The scenes which here occur are as remarkable for their difference of character from the preceding, as for SKY. LUCII SCAVIG. 'i8 1 tlieir orrandeur ; nor must they be passed without notice, though it is impossible to convey any idea of this spot, which before my visit had never been seen l)y a stranger, and was indeed known to few even of the inhabitants of Sky. Scarcely any but the shepherds had trod these sequestered retreats, the dwelling of clouds and soli- tude ; fit haunts for the poetical daemons of the storm.* * I have on a former occasion described the nautical circumstances under whicli I did not reach Barra Head: it will not he useless to describe those under which 1 accomplished a first visit to Loch Scavig. The itinerary of a traveller is often of advantage to his successors, while a single anecdote is often more characteristic of a people than a laboured description. The expedition was to proceed from Gillan on the west side of Sleat, and as a Highland boat is not soon set in motion, the crew was bespoke on the preceding evening. It was in vain that the orders were given for six in the morning, the men were not collected till nine, a Highlander being seldom ready, even for his harvest field, before ten o'clock. After the ordinary useless discussions we proceeded to the beach, but the tide had ebbed and the boat was dry : it could not be launched without further assistance. Before the requisite assistance was procured an hour liad elapsed. Being at length launched, it was discovered, that out of the four oars required, only one was present. It was necessary to procure the complement from a neighbouring village, and this was scarcely accomplished in another hour. Some hopes at last appeared that the day would not elapse in preparations, but of the pins required for rowing, only two could be found, swimming in the water which filled half of the boat. Sky not being a land of wood, some time passed before this little but indispensable requisite could be obtained, for which the teeth of a harrow %vere at length procured. We were now fortunately under way, the first stroke of the oars had been given, when an unlucky breeze springing up, one of the crew proposed that we sliould return for a sail. It was in vain to oppose this motion, too favourable to the natural indolence of this people, although it was not easy to conjecture how a sail was to be rigged on a boat which had neither step for a mast nor provision for a rudder. It was wrong to wonder at the latter defect, as the use of this contrivance is quite unknown in many parts of these islands. In less than two hours the trunk of a birch tree was procured, which, being fastened to one of the thwarts with some twine, was converted into a mast worthy of the first navigator. A broomstick, secuied to 282 SKY. — -LOCH SCAVIG. Locli Scavig is inaccessible by land on the north side; and equally so on the south to all but the active and practised mountaineer. The traveller, whose object is picturesque beauty, should enter it from Strathaird. In this direction the view from sea is extremely fine, the dark ridge of the Cuchullin, with all its spiiy and serrated projections, flanked by the equally dark and lofty ridge of Blaven, forming a varied and rugged outline on the sky. On entering the bay these siunmits disappear as they retire below the high skirts of the hills, which descend into the sea varied by projecting points and rocky islets, and surrounding the spectator with a con- tinuous surface of bare and brown rock scarcely present- ing a symptom of vegetation. The falling of a cascade, the deep dark green of the water, and the wheeling flight of the sea birds that frequent this retired spot, are the only objects which vary the uniformity of colour and of character it every where displays. On landing, similar scenes meet the eye in every direction, no in- truding object occurring to diminish the effect produced by the gloomy grandeur and savage aspect of the place. Passing the river Vvhich runs foaming over a sheet of this mast in a siaiilar iDaiiner, formed the yaid, and the sail was composed of a pair of blankets pinned together by wooden skewers and fastened to the broomstick by the same means. The want of sheet and tack was su[iplied by a pair of scarlet <;arters which one of the men stripped from his chequered slocking, and thus a ship was at length generated, not much unlike those of the heroic ages of which memorials are still existing in the sculptures of lona. It was two o'clock before this rigging was perfected and we were ready for sea. The want of a rudder being supplied by an oar, and the sail unable to stand near tlie wind, we made no way except to leeward, and there was a prospect of reaching Rum instead of Scavig; neither arguments nor authority being of the least avail with a people who, in spite of their practice, are utterly, ignorant of the properties and management of a boat. On a sudden a fortunate squall unshipped the helm, brought the sail aback, and the wiiole apparatus, too feeble to u[)sct tlie boat, was carried overboard. We reached our destination when we should have been returning, and passed the greater part of the night at sea. SKY. — CORUISIC. 283 smooth rock into the sea, a long valley suddenly opens on tlie view, enclosing the beautiful lake Coruisk, on the black surface of which a few islands covered with grass appear with the vividness of emeralds amid the total absence of vegetable green. On every side the bare rocky acclivities of the mountains rise around, their serrated edges darkly projected on the blue sky or entanoied in the clouds which so often hover over this region of silence and repose. At all seasons and at all times of the day darkness seems to rest on its further extremity : a gloom in which the eye, discerning but obscurely the forms of objects, pictures to itself imaginary recesses and a distance still unterminated. A remarkable contrast is hence produced in viewing alternately the two extremities from any central point. The entrance, less obstructed by mountains, presents the effect of mornino" rising to illuminate the depths of the opposite extremity, which appears as if perpetually involved in the shadows of night.* Silence and solitude seem for ever to reign amid the fearful stillness and the absolute vacuity around : at every moment the spectator is inclined to hush his footsteps and suspend his breath to hsten for some sound which may recall the idea of life or of motion. If the fall of a cascade is by chance heard, it but serves by its faint and interrupted noise to remind him of its distance, and of the magnitude of the mountain boundary ; Avhich, though comprehended by a glance of the eye, * It is not surprising that Coruisk should be considered by the natives as the liaunt of the water goblin or of spirits still more dreadful. A seaman, and a bold one, whom on one occasion I had left in charge of the boat, became so much terrified at finding himself alone, that he ran off to join his comrades, leaving it moored to the rock though in danger of being destroyed by the surge. I afterwards overheard much discussion on the courage of the " Southron" in making the circuit of the valley unattended. Not returning till it was nearly dark, it was concluded that he had fallen into the fangs of the Kelpie. 2S4 SKY. SOIL AXl) AGllICULTlJJiE. and as if within reach of the hand, is every where too remote to betray the course of the torrent. The effect of simplicity and proportion in diminishing the magnitude of objects is here distinctly felt, as it is in the greater efforts of architecture : those who have seen the interior of York Cathedral will understand the allusion. The length of the valley is nearly four miles, and its breadth about one ; while the mountains that enclose it, rise with an acclivity so great, that the spec- tator situated at their base views all their summits around him ; casting his eye over the continuous plane of their sides, as they extend upwards in solid beds of rock for nearly a mile and present a barrier over which there is no egress. Yet on entering it he will probably ima- gine it a mile in length, and fancy the lake, which oc- cupies nearly the whole, reduced to the dimension of a few hundred yards. It is not till he has advanced for a mile or more, and finds the boundary still retiring before him unchanged, and his distant companions be- coming invisible, that he discovers his error, and the whole force and effect of the scene becomes impressed on his mind. He who would paint Coruisk must combine with the powers of the landscape-painter those of the poet : it is to the imagination, not to the eye that his efforts must be directed. From the general description of the face of the island, its condition in an agricultural view will be readily collected. The almost absolute want of trees imme- diately attracts attention ; since the form of the land, often aflfbrding sheltered situations, is favourable to their growth ; while its small value for other purposes removes one of the obstacles to planting ; a branch of rural economy that would also be much aided by the facility so often here afforded for enclosing large tracts at a small expense. 1 SKY. SOU. AXD AGRICUI.TUIIF,. 285 With the exception of Bracadale, some parts of Trot- ternish and of Sleat, and a few smaller portions at Broad- ford, Snizort, Portree, and other places which I need not enumerate, there is no land in cultivation ; the greater part of the island being occupied by a system of pas- titrage almost limited to the production of black cattle. I need oifer no remarks on its agriculture after those which have been already made in describing the other islands : I may only notice generally, that a certain tendency to improvement has been manifested within a few years ; the ancient possessions in joint tenure haA ing nearly disappeared in the ameliorated system of separate farms ; v.'hile the division of the land into larger lots, and the accumulation of capital still required to produce permanent and extensive improvement, remain for future exertions ' and more favourable circumstances. Although the 2;reater part of the pasture of the island consists of moor land covered with heath and grasses of little value, many tracts of green herbage are to be seen, of which those about Loch Eynort and Trotternish are the most conspicuous. It is often difficult to determine the causes of these differences in the natural pvoduce of a given soil, where many are necessarilj'^ eiigaged in producing the effect. As far as its composition alone is concerned, the pursuits of the geologist are in some measure calculated to throw light on the subject. Yet even where an apparent identity exists in those rocks from the decomposition of which any soil is formed, there are often differences in the results that seem to elude all explanation. Sky presents some remarkable instances of this nature which it will not be irrelevant to point out in a cursory manner. It is already well known that many of the rocks of the trap family, like some lavas, afford on decomposition one of the most fertile soils with which we are acquainted. I have mentioned this fact on other occasions, and noticed at the same time the great differences which appeared 1286 hKY. son, AND A(; It ICU I/JURE. in this r«'sj)(:c.l. in ;c;ther with this ess(!nti'ordin<^- to the greattir or Icbb facility with which they uiid(Mjj,() decomposition. Wliere that takes place to a. (;onsiderable extent, the soil is com- monly not only deep but leilih', and will ollcn be found cov(!red with {^rcjen pasture, as on the eastern side of Trotternish and on the hills that surround Loch Eynort. Tliere are case« nevertheless where a, dei^p decomposition of the rock is to be kccmi, while tlu; p,round is still covered with peat and productive of little else than lieath. Tlii« SKY. — SOIL AND AGRICULTURE. 287 decomposition is occasionally so complete that in many places the rock, while it appears to retain its solidity with its form, can be cut through with a spade, and thus readily moulders into soil as soon as it is exposed to the effect of the rains or to mechanical force. The chief obstacle to this ultimate change must be sought in the covering of peat which invests the soil. This substance, scarcely pervious to moisture, prevents that access of rain which, united with frost, might perfect an incipient decomposition ; while, remaining for ages midisturbed, it also serves to conceal that which only requires exposure to become useful. An obvious improvement is thus sug- gested, namely, the exposure of the subjacent rock by the plough or caschroni; which in many cases, where the peaty surface is thin, is sufficient to generate at once a perma- nently fertile soil by mixing the carbonaceous matter of the surface with the earth that lies beneath ; a labour, in most cases, sooner or later recompensed by its effect in admitting the access of air and water, even where the rock is not actually mouldered. Such experiments must, of course, as in all other cases, be resolved into mere questions of expense ; but there are few where, if that can be tolerated, the certainty of the result is greater. Another remarkable anomaly of this nature exists in the calcareous district of Strath already described, pre- senting a difficulty of which there is no other apparent solution. The general fertility of calcareous soils is suffi- ciently notorious, and, in conformity to that rule, the existence of subjacent rocks of limestone can almost always be determined in the Highland mountains by the patch or stripe of brilliant verdure occurring in the brown waste. The district in question presents every variety of elevation, exposure, and drainage ; yet, with a small exception occurring in the lower parts of the valley, the surface is boggy, brown, and barren ; scarcely yielding in poverty of vegetation to the soils that lie on quartz rock, and, what is no less remarkable, almost every where 4 'i 8 8 s KY. — '■ A X V HiVl'l] K S . improductivo of tlie well known plants which are the usual inhabitants of calcareous land. On similar decli- vities and in similar circumstances, Lismore, Glen Tilt, and other calcareous districts of Scotland, are covered with the most luxuriant verdure. If this difference of result be incidental, as it can scarcely fail of being, it may perhaps, as in the instances of trap above mentioned, be attributed to the covering of peat, accumulated in ancient times under the shade of a forest of which the traces may be found in the buried roots and fragments of trees. It is indifferent what soil or what rock lies under such a substance, since its influence cannot reach the surface ; while, if the cause which I have here con- jectured be the real one, it adds another striking instance of the necessity of human labour in aiding the efforts of nature even where these are most bountiful. The last circumstance here worthy of notice respecting the connexion between the fundamental rock and the resulting soil, occurs in Sleat, towards the eastern coast. The rock here consists of gneiss, and, like the trap before described, is to be seen in many places completely decom- posed for many feet in depth, without any sensible alteration of its appearance or form, and only waiting the touch of mechanical force to reduce it into powder. Wherever this has already occurred, the consequence is a yellow loam of an excellent quality, rendering this part of the country one of the most fertile in the island. The relics of ancient art still preserved in the Western islands, are in most (;ases so little interesting that there is not much inducement to treat of them in detail. I have iu other places described a sufficient number to convey a general idea of their characters, and there is scarcely any thing in this island so particularly distin- guished as to require a minute notice. The most numerous ruins are those of the circular SKY. ANTIQUITIES. 289 strengths commonly called Danish, many of which are found on different parts of the coast; but all, as usual, so far destroyed as to convey but a very slender notion of their original state. Various monumental stones are also found, of which those near Loch Uig are the most conspicuous, if indeed they are not of Druidical origin. Whatever their object has been, the repetition of an- tiquarian conjectures would here be much misplaced. If there be any veiy ancient monuments in Sky at all distinguished from those of the other islands, it is the cairn on Ben na Caillich, visible at a great distance even on this elevated summit ; its magnitude bespeaking the importance of the person or of the event in com- memoration of which it was erected. I shall be excused from repeating the traditions respecting it, since they are unworthy of regard. The more modern remains are not numerous, nor, with the exception of Dunvegan Castle, are they very remarkable. A small portion only of the castle of Knock is still standing to bespeak its importance, but it seems to have been merely a castellated mansion. Duntulm is more entire, and, with dimensions equally limited, displays some remains of architectural ornament ; a circumstance extremely rare in the Highland castles, and seldom exhibited ^ with much liberality even in the low country, where greater opulence must have pre- vailed and more taste might have been expected. The very name of Dunscaich, the traditional resi- dence of the " King of the Isle of Mist," will naturally excite interesting associations in the minds of those who are versant in Gaelic poetry. But its interest is limited to its poetic celebrity. The present building is of recent date, nor is much of it remaining. If that which may have existed only in song be worth a con- • jecture, the residence of CuchulUn may with greater probability be placed on the neighbouring rocky islet, where the ruins of an ancient circular fort are still to VOL. 1. u 290 SKY.— ALLUVIA. be seen. Tt is said that vitrified frag-ments have also been found in the same place : I had not the good fortune to discover any, though I searched with great care.* CoNsiBERiNG the magnitude of Sky and the variety of surface which it presents, its alluvial deposits are trifling, and, except in one instance, possessed of no interest. It will be easily collected from the map that the indentations which form the sea lochs are in some cases determined, as on the continental land, by the valleys that are interposed between the ridges of hills, and in this case they are also the aestuaries of the rivers. But many of them are merely sinuosities of the general boundary, receiving no streams of note. To the former belong the narrow Lochs Slapin, Scavig, Brittle, Harpart, Eynort, Eishort, Sligachan, and Portree ; Lochs Bracadale, Follart, and Snizort, belong to the latter. Although the elevation of the country is considerable, and the climate among the most rainy of this kingdom. Sky affords no rivers of any magnitude, their course being; too short to admit of the accumulation of much water. The river which runs into Loch Sligachan carries more water to the sea than any other, and after it follow in order those which run into the Lochs Harpart, Slapin, Eishort, Bracadale, Portree, Snizort, and Broadford. The other streams are rivulets scarcely worthy of enumeration. The drainage of the whole country is determined by * I may here remark, that I have examined many vitrified forts since the period at which a paper on that subject was published in the Geological Transactions. The general conclusion that they were strong holds and vitrified by design, lias been confirmed by these examinations. It may also be remarked, that where no trap rocks are found, the vitrifiable ingredient has proved to be hornblende schist or gneiss containing hornblende. The wooded state of the country in ancient times removes any difhculty supposed to arise from the want of fuel. SKY. ALLUVIA. 21)1 the positions of the hills and sea lochs, and may readily be collected from the preceding observations. There are three or four fresh-water lakes, but of small size, and, except those of Coruisk and Colmkill, hardly worthy of the name. The courses of the streams exhibit but small traces of the wasting of the land. Like other mountain torrents they occasionally bring down rubbish and stones, but these bear no proportion to the accumulations of loose matter so common on the mainland in similar situations, nor do they oflfer any example of transported materials of which the origin is not to be traced to some neighbouring rock. Commencing at Loch Slapin, a considerable alluvium may be observed occupying the head of this Loch and extending up Strathmore ; encroaching on the top of the bay, and evidently formed by the waste of the Red hills, with additions comparatively insignificant from the naked precipices of Blaven. As the upper end of Loch Eishort receives no river of note, it presents no alluvial deposit; and no further marks of waste, encroachment, or alteration of the sea line, are to be observed round the point of Sleat till we reach Loch Oransa. Partial depositions of gravel may be traced from hence round the shore to Kylehaken, where a considerable bank of alluvial matter is to be observed, of which I shall presently give a more particular description. The shoaling of the sound of Scalpa, now almost fordable at low water, appears to be the result of similar deposits influenced by the concurring action of the tides through that strait; and it will probably at some future day unite the two islands into one. The head of the eastern Loch Eynort is also the receptacle of a considerable deposition of rubbish brought down from the Red hills ; a waste sufficiently great to alter the courses of the small streams which run through the narrow valleys that divide them. Similar, but more ex- tensive accumulations from the same cause have formed 29'i SKY. ALLUVIA. a tract of plain ground at the head of Loch Sligachan, subject to frequent inroads and changes from the still varying course of the stream. The waste of that land which supplies the river running into Portree harbour, appears also to have had some effect in filling up its southern branch with a deposit which the ebb of the loch has no tendency to remove. From Conurdan to the northern point of the island, the high cliffs of trap occa- sionally exhibit the species of decomposition characteristic of these rocks, in the vast slopes which decline from them to the shore wherever the action of the tide has not been sufficient to prevent that accumulation. Continuing round the point of Ruhunish, similar deposits are occa- sionally found 9.S far as Loch Snizort, at the end of •which, as well as of Loch Uig, the same appearances of waste are visible. The parish of Kilmuir offers the only considerable tract of alluvial land in Sky, from which its superior and long estabhshed fertility is probably in some measure to be explained. The shores of Loch Bracadale exhibit, when low, considerable portions of clayey alluvial soil, characterized, like those of Kilmuir, by extraordinary fertility. A similar alluvium may be observed at the head of Loch Harpart ; and the little valley of Talisker appears to have been fUtirely gained from the sea at some distant period, by a combination of the waste of the land with the counteracting efforts of the western swell, which has thus, as formerly noticed, formed a natural embankment for its further protection. A remarkable difference between the effects of the eastern and the western sea is to be seen along the western shore of the island from Dunvegan head to Loch Brittle. I already observed that the eastern cliffs were often covered by slopes of alluvial ground descending to the sea ; but the western, though formed of the same rocks, offer an almost continued precipice, the foot of which is every where washed by a turbulent swell. These SKY. ALLUVIA. $93 cliffs are in a state of daily ruin, and their bases are beset with enormous masses of rock which from time to time fall from them. The rocks called Macleod's Maidens, the islands in Loch Bracadale, and other de- tached rocks which skirt this coast, mark equally the gradual waste of the land. But no slope is formed against their faces, nor does any artificial shore accumulate at their feet, except a narrow interrupted stripe com- posed of fragments and almost impassable. The clay, sand, and smaller pieces are probably carried away from the coast far into the depths of the sea, by the incessant action of the western swell. Near Kylehaken an alluvial deposit of greater im- portance occurs, occupying a space of about a mile on the shore, but not exceeding a few hundred yards in breadth ; while it terminates on one side in the elevated ground, as it does in the sea on the other. It seems to be the remains of a plain formerly much more extensive, since its boundary towards the sea consists of a series of straight lines ; the loose materials assuming the usual angle, and exhibiting precisely the same appearances which characterize the terraces that line the alluvial valleys through which active rivers have cut their way. The bar of Kylehaken harbour, and the gravelly soundings of this shore which render it an insecure anchorage, equally indicate an extent once more con- siderable, and confirm the supposition produced by its straight edge and the angle of its declivity. The surface is about sixty or seventy feet above the level of the sea. No rivers at present flow in the vicinity of this plain, nor is there, from the form of the ground, any reason to suppose that they have ever flowed, so as to enable us to account for this deposit of loose ma- terials. The substances are nevertheless rounded, and consist of those rocks which are seen in the neigh- bourhood, presenting a large proportion of the various hard sandstones, with some occasional pebbles of gneiss 294 SKY. — ALLUVIA. and of hornblende schist. It might perhaps be imagined that the ordinary fragments of the mountains which back this little plain, descending to the sea and there rolled, might have been rejected by the tides so as to form these banks ; but this supposition is invalidated partly by the presence of gneiss and hornblende schist, which do not occur among these mountains, and partly by the altitude of the banks above the present high-water mark. It must doubtless be granted that if at some more ancient period the strait of Kylehaken was narrower than it now is, the same tide-wave which now passes through it would cause a much more considerable elevation of its tides. But it is already very narrow, and no possible contraction that can be imagined, would be sufficient to pioduce a difference of elevation so great as would be required fpr this purpose. It must be added to this difficulty, that the uniformly level surface of the plain is an insurmountable obstacle to this supposition. In defect of any other solution, it can only be supposed that this is a fragment of some ancient diluvian deposit, instances of which, although very rare in the islands, are sufficiently abundant upon every part of the continent of Scotland. No estimate can be formed of its original extent, nor can any valid conjecture be offered of the mode in yvhich it has been so abruptly cut down. It is however hkely that although the present direction of the tides is such as not materially to exert any action on it, that direction may have varied in the progress of' time, from alterations in the shape of the bottom of this very narrow channel, subjected four times in every day to the alternating action of a rapid stream ; as well as from the probable removal of a similar alluvium from the opposite shore of the mainland. As we find analogous causes producing daily and visible changes of the same nature in the courses of rivers, the supposition is not incompatible with facts ; since the narrowness of the Kylehaken channel and the rapidity of the tide, give it SKY. — GEOLOGY. 295 in this respect all the characters of an inland river as far as the contraction extends. We may perhaps indulge our conjectures still further in supposing that Sky was once united to the mainland by means of this alluvium, and that the gradual effect of the tide circulating through the bay on each side had at length produced the effect in question ; an effect not at all inadequate to its powers, and of which parallel examples occur in the lateral action of rivers on the alluvia of valleys ; as on the banks of the Tay and in many others of the principal rivers of Scotland. Greater effects have often been attributed to the corrosive powers of the sea. I may remark that the narrowness of the channel, which in one part does not exceed a quarter of a mile, and the shallowness of the soundings compared with the depth of those which separate the other parts of Sky from the mainland, are friendly to this supposition. These scarcely exceed ten fathoms in the middle, although there are some deeper holes on each side ranging to thir- teen, the bottom being every where gravelly, as if, like the banks, it was the remains of some former alluvium. The topography of the rocks of this island has been already noticed, and may be deduced with sufficient accuracy from the preceding remarks and from the map. The order in which they may be observed to follow each other may be described in a general way in few words. To gneiss, as the lowest rock, succeeds an alternation of graywacke slate, red sandstone, compact grey sand- stone or quartz rock, and common white quartz rock ; the gneiss in one part of its course passing by an insen- sible gradation into this series. After that follows a shelly limestone, alternating with shale, and with a crystalline limestone resembling those of primary formation. To this there appears to succeed again the alternation of red sandstone and graywacke schist described above, followed once more by the same shelly limestone and shale, each Q9() SKY. — GEOLOGY. GNEISS. of these portions of calcareous rock containing the same oblique gryphite ammonita, and terebratula. These strata are lastly followed by another set of stratified rocks, con- sisting of calcareous sandstone, limestone, and shale ; the whole being intersected and succeeded by different mem- bers of the trap and syenite family in the usual irregular and overlying position.* The arrangement thus briefly detailed is in some respects strictly geological, while in other points it will be found fallacious, as will be shown in the course of the ensuing detail. In entering on the description of gneiss as the lowest rock, it must be premised that I have chosen this term as a general one, to prevent repetition or prolixity where general features only were to be described. Respecting the varieties included under it, I need add nothing to the general remarks formerly made on this subject; but in describing the individual beds of this series, I have with mineralogists limited the term gneiss to its strict use ; distinguishing by a separate description those sub- stances which differ from it in structure or composition, and giving to the alternating rocks of other characters their received appellations. In choosing the most obvious character as the criterion of the upper or lower parts of any inchned series of beds, it is taken for granted, that no set of strata has been so entirely changed from its original position as to have passed the perpendicular and acquired the opposite dip. j3ut in the present case the upper portions are in reality determined by the rocks that follow, and we may therefore conclude the rule to be here inapplicable ; since the lowest portions of this gneiss are the uppermost in geological order, being in contact with those strata which are known from other circumstances to succeed in the order of super- position. It is nevertheless convenient to commence the description from this part of the series. " Plate XIV. liK. 1. SKY. — GEOLOGY. GNEISS. 297 At one extremity the gneiss is defined by a line com- mencing near a small indentation marked in the map oppo- site to Isle Oransa : it will hereafter be seen that at the opposite end of that line the boundary cannot be fixed ; a circumstance indicated in the colouring of the map. This line cannot be traced consistently even through the extent thus defined ; the accumulation of soil, and other causes, preventing a view of the rocks in many parts of the space over which it extends : but as the indications of a recti- linear course are every where predominant, and as the actual boundary is often visible, I have without scruple defined it by a precise line to the eastward of all those points where its limit has been actually traced. This line tends north-easterly, and will be found to regulate the direction of the edges of the gneiss beds wherever they are sufficiently persistent and elevated to give indications of their course. Their dip is toward the south-east, and will be found most constant and uniform wherever the rectilinear direction is most perfect. In one or two instances they subside to a very low angle or become actually horizontal, in a very few cases they are slightly displaced or bent, and in one or two only I observed the dip to be reversed. The angle of elevation varies so much in different places that no rule of general application can be given. Angles varying from 20° to 40° appear to be the most frequent, but towards the south- western extremity of Sleat they occasionally become vertical. Some of the minor disturbances and contortions seem to arise from the trap veins, which are abundant, traversing the gneiss in every direction. The others must be referred to the causes that have influenced the general arrangements of this rock. The laminar structure prevails in the gneiss of Sky, which is identical with a very large tract of the same rock to be found in Glen Elg on the opposite mainland. Not only are the beds regularly disposed in parallel planes, but the structure of the rock corresponds to 298 SKY. GEOLOGY. GNEISS. these, each substance that enters into its composition forming a separate lamina more or less extensive. No granite veins are to be seen, or, if they exist, they are rare, since none occurred throughout a very extensive and minute examination. I have formerly attempted to show that the contortions and irregularities of gneiss v/ere accompanied by the presence of granite veins : the present example seems to confirm that view, while it also proves that they are not necessary to its constitution. The predominant feature in the composition of this gneiss, is the abundance as well as the distinctness and red colour of the felspar, which is seldom entirely absent, even from those accompanying rocks of other characters that will hereafter be described. In the greater number of instances it is interlaminated chiefly with quartz ; mica entering into the structure in very small proportion, and commonly occupying a distinct and thin lamina. In some cases the mixture is more confused, but gene- rally the mica is even then in very small quantity. This variety of gneiss has a very peculiar appearance, from the contrast of the red and white colours ; and, where the laminae are even, it forms a beautiful rock. The next variety consists of chlorite schist, felspar, and quartz, and here it may be a question whether, mine- ralogically considered, such a compound ought to be called gneiss. In the meantime, from the want of another name, from general similarity of character, and from tlie nature of the transition by which it passes into genuine gneiss, it may be allowed to stand as a variety of that substance.* In fact it is no further distinct than are the varieties so abundant in the Long Isle that contain hornblende in lieu of mica ; which have without scruple been ranked by geologists under the same term. These occur also in Sky, and, commonly, more or less intimately associated with the beds of hornblende schist that alternate with the gneiss. * I have alfciuly so arraiij^cd it in tlic SyiTDpsis uf Gneiss. SKY. GEOLOGY. GNEISS. ^99 Together with these, which are the most marked and the predominant varieties, micaceous schist of two or three distinct aspects occurs. In general it forms beds of but small extent, the gneiss soon recovering its pre- dominance ; but in one or two places, masses of 100 yards pr more in thickness are to be seen. The beds of hornblende schist that alternate with the prevailing rock are sometimes simple, at others compound, containing felspar : they are frequently conspicuous for their magnitude. Beds of chlorite schist passing into talcaceous schist, or into pale blue argillaceous schist, or into a graywacke, are also found in different places ; and in some cases the mixture or alternation of the former rock with the felspar and quartz that prevail in the gneiss, is such, and the chlorite schist so predominant, that it is difficult to say under which of the two substances it ought in prefer- ence to be ranked. A gradual change s.eems to take place along the eastern coast, from the simplest gneiss, which occurs near Isle Oransa, to the irregular varieties, which predominate at Armadale : while, as we proceed further to the south- west, the schistose ingredient increases nearly to the exclusion of the others. The last stage of the transition from gneiss to chlorite schist is effected by a rock as yet without a name ; a compound of chlorite schist and felspar. There are two varieties of this ; a laminar one, in which the two substances alternate and the external characters of gneiss are maintained ; and another, in which the irregular laminse of the schist are intermixed with arena- ceous grains of felspar, so that the usual characters of gneiss disappear. Other anomalous substances, which it is necessary to mention, are found in connexion with these rocks. One of these consists of a white felspar traversed by long prismatic needles of hornblende, and it occurs in a separate bed near Loch Oransa. In another, actinolite enters into 500 SKY. — GEOLOGY. GNEISS. the compound ; and in a tliird case, quartz and felspar alone are united, sometimes in an indiscriminate mixture, at others by a dispersion of distinct grains of red felspar through a highly crystalline translucent quartz. This rock has been already mentioned as occurring in Tirey. I think it unnecessary to enumerate any more varieties, and would willingly have avoided the detail of these, had it not been requisite to prevent misapprehension from the use of the general term gneiss. Without such precautions mineralogists can scarcely hope to understand each other; they are, like definitions, calculated to prevent mistakes. In recurring to the changes in the composition of the gneiss between Loch Oransa and the point of Sleat, it must be remarked that this line is that of the direction of the beds ; and that the change takes place therefore not by alternation or succession of beds, but in the pro- longed course of the same set. Whatever difficulty may attend the explanation of this circumstance, it is not con- fined to this rock ; nor is this, even here, a solitary case, since it will be seen, in describing the strata which follow, that they also are subject to the same irregularity ; and in a degree fully as great, or even greater, since more at variance with the usual appearance of rocks that are in general very constant in their characters. I must here drop the subject of the gneiss unconcluded, since that which remains is so intimately linked with the history of the next series of rocks, on account of the transition between the two, that it would not now be intel- ligible. I shall therefore proceed to consider this series in an order as regular as its ambiguous character permits. In adopting a general term, something must here, as usual, be sacrificed to the convenience of using one only ; I have therefore chosen the name of that which appears the most characteristic, if it is not the predominant sub- stance, to wit, red sandstone, as it would be otherwise impos- sible to render the geological description intelligible. The latitude of this term is undoubtedly great, since various SKY. GEOLO'GY. RED SANDSTONE. SOI schists and other substances share largely with it in the tract to be described, but the adoption of either of these would have been still more objectionable. It was already shown that the boundary of the gneiss at Loch Oransa is definite, and from this point it will be most convenient to commence the present examination. But it is impossible even thus to pursue this investigation in the usual regular order from the lowest to the highest of the entire series, even if the lowest could actually be ascertained throughout the whole line. The causes of this will be found to consist in the varying composition of the beds, taken longitudinally, or according to their direc- tion. Hence it happens, that although certain portions are regularly prolonged in the rectilinear direction, they will be found to present different substances throughout their course, just as they do when examined transversely, or according to the order of their succession. It will therefore be necessary to select certain portions of the whole in a transverse order ; noting the chief differences that occur, and connecting them as much as possible by those features which are common to all, namely, their dips, bearings, and connexions with the rocks above and below. With trifling exceptions, which will be noticed in their proper places, the bearing of the whole series corresponds to that of the gneiss, and is thei-efore north-easterly. But the dip is so various and uncertain that the record of the particulars must be referred to the details of parts, since it is in different places both easterly and westerly under various angles ; while the strata often assume the vertical position also. As the most systematic regularity of the gneiss is found near Loch Oransa, so the position of the red sandstone is there also most uniform. The gneiss at this place is of a decided character, and is followed towards the north-west by a few thin beds of micaceous schist ; unless the presence of occasional grains of felspar only distinguishable by the lens, should induce mineralogists to consider this rock as a variety 302 SKY. — GEOLOGY. RED SANDSTONE. of gneiss. A space succeeds in which no rock can be detected, vegetation and alhivial soil occupying the ground in the interior, and gravel covering it on the sea beach. It is not improbable that these conceal some conglomerate; this being the natural position of such a rock, of which, in fact^ portions are occasionally found in the interior country adjacent, without any other assignable con- nexions. This vacant space is succeeded by a yellowish quartz rock, accompanied by a schist, which although it very often presents the characters of a clay slate, yet, more commonly exhibiting those of a fine graywacke, will pro- bably be ranked with it by most geologists. I shall not be anxious hereafter to distinguish the different varieties of this rock, as the geological relations of all are the same. The nature of the succession now described is so simple, and so conformable to the received order of rocks, as to lead to the natural conclusion, that the gneiss is regu- larly followed by micaceous and by graywacke schist ; and were the investigation suspended here, as might easily happen, an observer would decide on it without hesitation : yet he would in this instance, as perhaps in others, substi- tute system for fact. Where these beds of schist first appear, they are con- formable to the gneiss in dip ; but they almost immediately become reversed, and are found dipping to the north-west, yet witliout any change of character or direction. The angle of the dip is here from twenty to thirty degrees. Fresh substances shortJy after make their appearance, and a rock with the characters, at times of quartz rock, and at others of common hard sandstone, and of various colours, wliitish, blueish, or brownish grey, is found in repeated alter- nations with the graywacke schist. Approaching towards the end of Loch in Daal these beds become nearly hori- zontal, the elevation varying from five degrees to ten, but the dip continuing still westerly. Further on, it SKY. GEOLOGY. RED SANDSTONE. 303 increases to thirty degrees or more, and tJien becomes again reversed to the eastward, under which inclination it continues for a considerable space. The north-eastern direction of the edges of the strata still continues, and, to avoid repetition, this must be understood to be a con- stant feature where the contrary is not expressed. The reversal of the dip takes place in Ben na Ree, and the eastern dip, being once established, is traced towards the K)de rich for a considerable space, when it is again reversed to tlie west. If the line of this shore be traced to Ben Ashlaig it will be found to correspond to the direction of the strata, and thus far therefore we have access to one limited set of beds only, along this whole line. Their characters throughout this space are very constant and uniform, since they consist entirely of the schist already mentioned, interlaminated Avith quartz rock of the same grey colour. The appearance of a regular succession of graywacke to gneiss is thus preserved for a long space, since the geologist does not easily discover that he is proceeding on one line only of the stratification. This conclusion is only invalidated by afterwards finding that no progress has been made across the strata, and that the beds not only change their natures in the course of their prolongations, but that the same schist alternates with the various sandstones even to the last moment of their recurrence in the order of succession. It is necessary here to mention a small portion of gneiss, too trifling in extent to have found a place in the general account of that rock, but important notwithstanding its smallness, since it serves to indicate the continuous regu- larity of the bearings, as well as to prove the alternation of the gneiss with the sandstone series. It is to be seen at the foot of Ben Ashlaig, being marked in the map, and it will be found to project a little beyond the linear boun- dary of the coast which, as the map will also show, is con- tinuous with that of the sandstone near Loch Oransa. It thus serves to indicate that the gneiss of Sleat and that of 304 SKY. GEOLOGY. RED SANDSTONE. the opposite mainland are separated by the body of sand- stone which Hes to the south of Island Reoch and is succeeded by the gneiss of Glen Elg;. Its character resem- bles that of the southern parts of Sleat, consisting of laminar felspar and chlorite schist, connected with mica- ceous schist and passing gradually into graywacke. Resuming this series as it is displayed along the sea line, the alternations of schist and quartz rock are found to be succeeded by great tracts of the quartz rock-alone, here, as before, generally very compact, though occasionally acquiring an arenaceous structure. It is at first of a lead blue, then grey, brown, reddish, or mottled, under some of which modifications it might with equal propriety be called an indurated sandstone. In composition it is subject to another material variation ; the quartz becoming mixed with felspar of the same colour, so intimately, that the mixture can scarcely be detected but by the weathering of the surface, which becomes harsh and rough ; the one substance decaying while the other remains. In some cases the proportion of felspar is so great that the quartz nearly disappears, the rock when weathered being easily recognised by the whiteness of its surface, and, though less easily, by its recent fracture. I have called it felspar from the result of its decomposition ; it may belong per- haps to a class of substances (the compact felspars) which mineralogists have not yet considered with the attention they merit. With no material change, the same substances continue all round this promontory by the Cailleach stone and Loch na Best to Moil Castle ; and in this direction, nearly the whole series is traced transversely from its commence- ment to its termination.* For a long space the predominant dip is towards the south-east, but the beds occasionally • Plate XIV. fig. 3. Tliis section will convey a genrml idea of ibc positions of the strata, sufficient f r the purpose of tlucidating the changes they uudergc). SKY. — GEOLOGY. RED SANDSTONE. 305 become vertical. If this portion of the whole mass alone were considered, it would be concluded that the sandstone series was conformable to the gneiss, but it has already been shown to have the reverse position at its commencement, and will hereafter be seen to be simi- larly placed, not only at its termination, but in many intermediate places along the courses of the beds. Although the schist is not abundant throughout the space which extends from the Kyle rich to Moil Castle, it is never altogether absent; while it again recurs with increased frequency and unaltered characters as the series approaches to its termination and assumes the more ordi- nary character of red sandstone. At Moil Castle this character first becomes dis- tinct ; the individual grains of felspar and quartz being visible, and the rock in some places assuming the aspect of a coarse grit. On passing this point the beds become vertical without any change of composition, and then gradually inchne to the westward ; still preserving, for a long space, even where least elevated, an angle of not less than thirty degrees. Here, the blue quartz rock, the schist, and the red sandstone alternate ; while the beds in their further progress upwards subsiding gradually to lower elevations, tenninate at length in an angle of ten degrees, on the shore near Lucy, where, after the intervention of a sandy bay that conceals the point of change, they are followed in the same order by the lime- stone ; the last beds for a considerable space consisting of an ordinaiy red argillaceous sandstone. Such is the order of the north-eastern natural section of this series, and as the direction of the beds is rectihnear, it might naturally be concluded that the history of this portion would be that of the whole mass through its entire extent. This conclusion is proved to be fallacious by the examination of other portions. In a country so encumbered with deep soil, such access cannot always be had to the rocks as to enable us to VOL. I, X oOG SKV. — GEOLOGY. RED SANDSTONE. trace all llio changes that occur ; but the obKcrvations made in the interior include the rnoBt essential circum- stances, and are fully justified by corresponding remarks rruide on the south-western shore oi' Sleat where the rocks are fully open to investigation. The low valley that stretches northward from Loch in Dual does not interrupt the continuity of" the strata, though it intersects the whohi series, lietween this valley and the lijie oi' coast just described the beds in the interior aie, as far as can be discovf;red, con- sistent throughout, but in the opjjosite direc^tion some considerable irregularities take jiiace, which must next be examined by assuming a fresh jjortion that may be included between this spot and a transverse line crossing to the north-eastward of Ord. Fortunately the two shores of Loch l^ishort are included in this division, and we are thus materially assisted in verifying observations less satis- factorily made among tlu; boggy wastes of this obscure and difiicult country. Tracing from Loch in Daal to the west, the lines of bearing of the schistose beds, and of the varieties of quart/ rock that accompany them, are (ountl con- tinued to the head of Loch I'jshort with tiie usual easterly dip. liiit here that dip becomes suddenly re- versed, while some beds are found in a vertical position ; these, although they <;annot be consistently traced, being probably situated ljetwer;n those of westerly and those of easterly inclination. Ib;re also the ordinary red sand- stone makes its aj>p(;arance, first alternating both with the schist and the blue rock, but shithstanding certain differences of character however, such is its general resemblance to the uppermost strata of the remainder of the island, such its position and dip, and so near its place to that of Swishnish, that there can be no hesitation in admitting it as a member of the same series ; separated from all its natural affinities either by the overlying trap or by the surrouiiding sea. This rock extends from the termination of the trap on the western side of the promontory, round the point of Aird to nearly the upper end of Loch Slapin, preserv- ing a great evenness of direction and consistency of cha- racter throughout this space. It is called a sandstone in a general sense only, as it will be seen that it also contains beds of limestone, but in small number and 348 SKY. GEOLOGY. SECONDARY STRATA. of very limited dimensions. The position of the beds is so nearly horizontal that it is rarely found to vary 5°, except on the western shore, where it occasionally ranges to 10 and 15°: the dip, like that of all the stratified rocks, is towards the west, the smallness of the angle in this, as in all similar cases, preventing its tendency, like that of the direction, from being more accurately specified. There is a peculiarity in the structure of these beds so remark- able, that it is necessary to point it out, and as it is dif- ficult to render it intelligible in words, I have added a diagram* for illustration. Each stratum seems compounded of two parts, the one consisting of a single horizontal lamina, and the other of an inclined series ; or, there is a reo;ular alternation of a set of inclined with one horizontal lamina. These are perfectly defined, the intervals being deeply channelled by the weather, and the whole having the aspect of some of the carved ornaments of Saxon . architecture. This appearance conveys, on a first view, the idea of a regular series of beds alternating with each other, of which the one is horizontal, and the remainder in an unconformable position to it. But it must rather be considered as the indication of an in- ternal structure, of which however all marks disappear when a fracture is made ; a case analogous to that which occurs in basalt and many other rocks, of which the internal structure is so often detected by the changes which they undergo on exposure to the weather. A similar case, which is described in the argillaceous schist of Isla, serves to confirm this explanation. The appear- ance in this latter instance so exactly resembles the present, that the same drawing will almost serve to represent both ; and the nature of the cause is amply confirmed by this circumstance, that while the beds of the schist are appa- rently divided in the direction marked by the horizontal lines, they are fissile only in that which is marked by * I'hitc XVJII. n^. 2. SKY. GEOLOGY. SECONDARY STRATA. 349 the oblique. It hence also follows, that if the fissile property of clay slate is the result of some internal arrangement analogous to crystallization, we are equally entitled to attribute the structure of this sandstone to the same cause. The inclination of the oblique laminas to the horizontal, varies from 10° to 30° ; but it is regularly in the same direction, the dip, if it may be so called, being to. the south. This appearance is neither rare nor dubious, but is extremely well marked, and predominates throughou.t the whole range. The measure- ment 'of the parts having been mislaid, it is from recol- tion that the intervals between the horizontal lines are here stated to vary from one foot to a foot and a half. There is no difference in the quality of the two sets of laminae, both being of white sandstone, generally more or less calcareous.* To enter more minutely into the composition of these beds, I may now remark that the sandstone often acquires the aspect of some of the most compact and crystalhne varieties of quartz rock, while in other cases it has the lax texture of an ordinary freestone. In some places it is calcareous ; the calcareous matter varying so much in quantity that the compound would sometimes be called a calcareous sandstone, while at others it would be described as a siliceous limestone : in the latter cases it is often dark brown, grey, or even of a dark lead blue. The beds of mere limestone are rare, and those which I observed lie towards its upper boundary : they * Having mentioned the resemblance vvliich the channelled surface of this sandstone bears to certain architectural ornaments, I may point out to artists the probable origin of some varieties of the hatching and vermiculation of rustic work, in the various modes of weathering dis- played by many of the sandstones. In niany instances the imitation of art is perfect; and among other places I may name an example at Roslin Castle, where the i-esemblance is so strong that it is at first sight difficult to believe that the chisel has not been employed in giving the stones their present a[)pearunce. 350 SKY. — GEOLOGY. SECONDARY STRATA. are much more generally granular than compact, and some of them indeed formed of an aggregate of rounded grains of the size of mustard seeds ; not much differing from some of the oolites, but more compacted, and generally containing, besides these grains, ciystaUized platy particles. These strata are intersected in a re- markable manner by trap veins ;*' but I shall defer the consideration of those to their proper place, the last in the history of the rocks. Reasons will hereafter be produced for supposing that these veins proceed from the great masses of trap vs^hich cover all the northern portions of this promontory ; and these circumstances may perhaps assist in explaining the differences in character between the strata of this shore and those of Swishnish opposite to it. The examination of the southern and western shores of Strathaird itself will show that similar differences exist among these strata, even where they lie near each other and admit of being continuously traced. On the eastern side of the pro- montoiy and towards its southern extremity, the trap veins diminish gradually in frequency till they nearly vanish altogether, and about the same place the incum- bent trap also ceases. Here the sandstone is found with its most ordinary characters, tender in texture, often calcareous, and generally white, but sometimes grey or brown so as not to be distinguished from that of Swish- nish. It occurs in the same form on the western shore of the promontory, where no trap exists ; and it here possesses the same complicated schistose structure as the hard strata ; but more perfectly, inasmuch as the laminae actually separate to a considerable depth by the action of the weather. If the dips of the strata on both shores are now compared, it will be seen that the same bed which is hard in one place is soft in another ; this differ- ence being regulated by the presence or absence of trap. * Phitc XVJ. fi!:. 1. SKY. — GEOLOGY. SECONDARY STRATA. 351 There is consequently sufficient evidence of the identity of the hard and soft strata, and therefore of the original continuity of those of Strathaird with those which now Ue at Swishnish separated by the breadth of the loch. Omit- ting the character of hardness, there is a striking similarity between these different strata ; the same varieties in colour and composition occurring both in the soft and in the hard ; the grains of sand also that form the body of the rock being in the one case loosely aggregated and separated by calcareous matter, in the other condensed almost to the state of quartz, and in some instances converted into a cherty substance by a combination with the lime. It is needless here to dwell on the obvious explanation of these changes which the presence of the trap offers; since it is so nearly connected with many analogous phenomena that will be described in other parts of this work. With these strata the description of the regular rocks of Sky terminates; but it will not be useless to bring under review the connexions of the whole, for the purpose of examining the analogy which they bear to similar rocks occurring in other situations. This is rendered the more necessary by the numerous irregularities they present; by which their natural order is so far obscured as to add materially to the labour of the geologist, and to interrupt equally that consistency of description with which their history might otherwise have been given. These increase nevertheless the interest of the phenomena ; presenting at the same time a valuable set of facts for explaining analogous derangements of a less obvious nature, and affording useful lessons to the geologist who may engage in similar investigations. It has been shown that the position of the gneiss is regular, and that under peculiar modifications it is followed by a series of sandstone, equally regular, of which the mejmbers are, with' trifling exceptions, similar or analogous throughout, and persistent across the whole island. These 352 SKV. GEOLOGY. SECONDARY STRATA. rocks are not limited to the island alone, as their pro- longations can be traced with the same regularity to the mainland and the adjacent islands, under no greater anomalies than can be accounted for by the trap rocks associated with them. Immediately after this series follows a deposit of which limestone is the principal member. In the vicinity of the regular sandstone these beds maintain a nearly un- violated regularity of position; the exceptions which occur, arisino; from a minor degree of those circumstances that accompany the greater irregularities. But as they proceed upwards, the regularity of this disposition becomes ma- terially affected, while they undergo considerable changes of structure; the outer boundary of the zone thus pre- senting a very irregular line, marked by the disturbance of some beds and the total deficiency of others. In analogous cases, where such rocks are followed by other secondary strata, they are equally regular at their upper as at their lower boundaries ; these strata, here as elsewhere, consisting of shale, sandstone, and calcareous rocks, and the whole presenting a well-known set of natural affinities- Together with these regular secondary strata, there are here found in many places a set of unstratified rocks, reposing on them, occasionally alternating in an irregular manner, and ramifying into veins of greater or less magnitude. If the contact of these overlying rocks with the strata be examined, it will be found that they are rarely parallel except for a small space ; and that instead of lying upon them in an even manner, they join them obliquely or transversely, or meet them in other irregular modes. With similar irregularity, portions of the unstratified rocks intrude among the stratified, or fragments of the latter are found insulated among the former. Where the limestone loses its order and disappears, a great mass of those unstratified rocks occurs, rising into high mountains and occupying nearly all the northern SKY. GEOLOGY. SECONDARY STRATA. 353 part of the island. This irregular mass commences at the northern side of Strath, at the upper boundary of the limestone series, and terminates partially at Loch Sligachan, being succeeded for a small space by a second portion of stratified substances. These are again interrupted by a second mass of unstratified rock, which although thus divided on the eastern side of the island, unites into one continuous mountain mass at a small distance westward. On the eastern coast, immediately succeeding this portion of unstratified rock, a sandstone totally disunited from all the former strata appears ; being repeated with similar interruptions for a consider- able distance along this shore, and finally appearing on the western side of Trotternish under equal circumstances of irregularity.* The chasm in the strata thus produced here by the unstratified rocks, is filled by Rasay, Scalpa, and Pabba; and a series may thus be traced among the several islands, scarcely perfect in any one, but most continuous in Rasay; while in Sky it is so interrupted as to be undeterminable without their assistance .f The order of the whole is as follows ; gneiss, red sandstone, gryphite limestone, white sandstone, limestone, and shale ; the intermediate alternations being neglected for the purpose of condensing the series. In thus replacing the scattered parts, the white sandstone of Trotternish becomes approximated to the inferior limestone, and restores that continuity which the present statement was intended to establish. It may be added that the order thus circuitously traced on the east side of Sky is more visible on the west, where the immediate sequence of the upper sandstone to the gryphite limestone has so lately been described. It is next necessary to inquire respecting the resem- blance of these to analogous rocks found in other places. * PI. XIV. %. 1. t PI- XV. VOL. I. A A 354; SKY. GEOLOGY. SECONDARY STRATA. The oro;anic remains of Rasay have been shown to re- semble those of Somerset and Gloucestershire, and they determine the series in that island to be analogous to the lias of the English strata. Even without this evidence, the limestone of Trotternish, with its accompanying shale and sandstone, exactly resembles many of these beds as they are found in England and Ireland, between which latter and the Western islands of Scotland there are some strong points of correspondence. It will hereafter be seen, in examining the general connexion of all these islands, that portions of the same series are found scattered throughout the whole ; extending thus the boundaries of b. formation which has been found in other parts of Europe. We are not at present acquainted with all the marks that distinguish the limits of this series, nor is it by any means certain that our knowledge of organic fossils is sufficient for this purpose ; were it even proved that there is a constant and inviolable relation between one series of rocks and one set of fossil species. Under these circumstances it may be questioned whether the gryphite limestone of Strath appertains to the lias ; yet geologists will perhaps consider it the lowest part of this series. If this be established, the lias here reposes immediately on the primary rocks, to which I have shown the red sandstone to belong; the intermediate strata, which occur in England and in other places, being absent. Such irregularities are too well ascertained to be now any longer subjects of doubt; and they will confirm to geologists the propriety of limiting their conclusions respecting the continuous nature of the rocks that occupy the earth's surface. Before proceeding to the unstratified rocks which constitute the remaining and larger part of this island, it is necessary to describe some stratified substances connected with those that have already passed under review, but which being of an incidental nature could SKY. — GEOLOGY. SILICEOUS SCHIST. 355 not have been examined without interrupting the order of the preceding account. These are, siliceous schist, chert, and coal; and as the two former occur in the same circumstances, and occasionally in conjunction, their history may in a great measure be united. These are found in detached fragments under the hio-h cliffs on the eastern shore of Trotternish, oc- currino- in considerable abundance and variety among the fragments of the common strata that strew this beach. The coast is very difficult of access even in fine weather, and with a wind off shore ; in other cases it cannot be approached, and, as the cliffs are perpen- dicular and inaccessible, the natural position of these substances cannot be discovered even after a successful landing. As it is only by the colours, the dimensions of the strata, and similar indications, that we can judge of the nature of the different rocks in these cliffs, there are no means of distinguishing between those beds that consist of common shale and those that may be formed of siliceous schist, and we must therefore be here content with examining the fallen fragments. But as these substances are accessible in other parts of Sky, disposed among the ordinary strata and accompanied in the same manner by trap, we are justified in con- cluding that they exist in the eastern cliffs in the same positions. The sihceous schist presents various tints, varying from a pale to a dark grey and to an intense black. Occa- sionally the two colours are found disposed in stripes perfectly even and parallel, presenting a singular ap- pearance when long rolled on the beach, as the grey variety becomes white on weathering while the black retains its original hue. On fracture, the cause of this appearance is found to consist in the alternation of laminae of different colours; many of the fragments resem- bling striped jasper, some of the well-known specimens of which are evidently but varieties of this substance. 356 SKY. GEOLOGY. SILICEOUS SCHIST. It may be said generally, that the blackest varieties are the hardest, and approach most nearly in their fracture and lustre to flint, although there are some exceptions to this rule. These are also the most brittle, and they are often indeed so fragile as to fly into small pieces before the hammer, rendering it difficult after numerous trials to procure a single specimen. It is in this state that the siliceous schist is known by the name of Lydian stone. While some of the specimens have the lustre of flint, others present a dry earthy surface, and with this aspect they commonly offer greater resistance to the hammer. The fracture is in all cases more or less conchoidal, but is largest in those specimens that present a dull surface ; in the most flinty varieties a conchoidal and, angular fracture are combined. Some- tunes the fragments are found united to limestone in a parallel manner, clearly proving their original connexion; and in these cases the limestone, instead of the usual earthy aspect, presents a crystalline texture. The fragments of chert are equally abundant, but being of a more durable nature are found of a larger size. They vary in colour from a greyish white to blueish grey ; sometimes they are mottled, and occa- sionally they exhibit tints of greyish green. The fracture is commonly plain, or very large conchoidal, but so dif- ficult to produce, that a hammer of four pounds weight is often insufficient to detach a single specimen from the block. Now and then they are somewhat more brittle, but in every case the thin fragment when pro- cured has the sharpness of glass with a toughness ap- proaching to that of iron. This chert strongly resembles that which is entangled in the pitchstone of Egg; still more nearly that of the Shiant isles, which will hereafter be shown to originate in the same substances, namely, the different beds of the lias limestone. That evidence which is here wantino; with regard to the natural position and affinities of the chert and the SKY. GEOLOGY. SILICEOUS SCHIST. 357 siliceous schist, is fully supplied by the appearances on the western shore of the same promontory ; and as the examples that occur there in situ belong to the upper beds of the series where they are in contact with the super- incumbent trap, it is probable that the fragments on the eastern shore have been detached from the same parts of the deposit. While the connexion between the sili- ceous schist and the chert is here found perfect, the two substances alternating as the limestone and the shale do in the beds immediately succeeding, we can also trace among the different examples a perfect series of transition from the natural to the indurated state. This is perhaps most striking in the shale, which passes by imperceptible degrees into the most perfect Lydian stone. In the case of the chert there is less regularity, but the difference is easily explained by attending to the composition of the original limestone beds. Where these have been tolerably pure, they seem incapable of under- going any change but that of crystallization ; where the other earths have been in excess, they are converted into cherts of various degrees of hardness, in which the calcareous ingredient can no longer be detected by the ordinary methods; the several earths having combined, as in the case of pottery, into a substance not unaptly to he. compared to it and requiring methods of analysis equally powerful. In all the specimens of the shale and Lydian stone, shells are occasionally found. Mr. Pennant mentions ammonitai : I have only observed minute bi- valves, their shells being very thin, but the forms so nearly obUterated that it is impossible to conjecture even their affinities. They are never abundant, but I may remark that they are rare in this part of the series, even among the unaltered strata. Although in some instances the actual contact of the trap with these indurated strata is here to be seen, it is not alv/ays found, apparently in consequence of the degradation of the rocks ; but one very perfect and 358 SKY. — GEOLOGY. SILICEOUS SCHIST. satisfactory example occurs in the mass of rock under Duntulm Castle ; in which also it is evident that the influence of the trap extends through a considerable space from the immediate contact.* That influence is however palpably variable in extent; a circumstance not difficult to explain when we consider the relatively variable bulks of the stratified and of the interfering rock, and the other numerous variations to which their connexion may have been subject. The strata in question form a mass, of which the base is covered by fragments, but the visible thickness is about twelve or fifteen feet. It is surrounded on all sides by the mass of obscurely columnar trap under which it lies, the junction being in many places attended with great con- fusion. The upper strata alternate with similarly thin beds of an indurated sandstone, the whole precisely resembling those alternations of shale and sandstone which occur along this shore. It is not indeed till fragments of the rock are examined in the hand, that the spectator can imagine he sees any thing but a bed of shale alternating with sandstone : but on thus examining the schist, it is found to be an extremely brittle and hard substance, of a black colour, giving fire freely with steel, sharp in the fragments, and with an obscurely rhomboidal fracture com- bined with the conchoidal ; this last character being the only one by which it can be distinguished from the fine grained basalts, particularly from those which occur in the form of veins in the Cuchulhn. The sandstone laminae possess at the same time the hardness and jaspideous aspect of that which I have described in the Geological Transactions as lying in contact with the greenstone of Stirling Castle. Considering therefore the analogy of these two sandstones both in aspect and position, we may fairly conclude that they have in both these instances been al- tered from their original texture, in consequence of the * Plate XVI. fig. 2. SKY. — GEOLOGY. SILICEOUS SCHIST. 359 proximity of the trap rock. The alternation of the two substances here described, which have doubtless been originally shale and sandstone, similar to the unchanged specimens occurring in various parts of this shore, gives us an equal right to conclude that the same influence of the neighbouring trap v/hich converted the sandstone into its present form, also converted the shale into Lydian stone. The position of every specimen of siliceous schist or Lydian stone which I have seen in Scotland is analogous to this. In Cruachan, in Rasay, in the Shiant isles, at Talisker, and in Scaipa, it forms beds, in contact with and involved either in granite or in trap, which, from their connexions and positions, appear to have been common clay slate in those cases where it belongs to the primary strata, and shale in those where it forms a constituent of the secondary. It is possible also that the grey varieties of this substance may, in certain cases, have originated from common slate clay, and the Lydian stone from black shale. Between this Lydian stone and fine grained basalt there is often no assignable difference of character except that of the large fracture, a circumstance perhaps neces- sarily resulting from the unaltered stratification of the former. Nor is there any reason to doubt this resem- blance, since the same materials under a different form probably compose both rocks. Chemical analysis un- fortunately offers no temptation to try this analogy further, since the variable composition of basalts as well as of schist, a variation necessarily arising from the circumstances of their formation, would prevent the possibility of comparing any two specimens even of the same substance. It is interesting to inquire by what power the vicinity of trap operates in influencing the change from shale to Lydian stone, as well as in producing the much better known changes which occur in the sandstone bordering on it. If basalt has been produced by the fusion of beds of slate, the necessary analogy 360 SKY. GEOLOGV. COAL. between the Lydian stone and that rock will appear conspicuous, and we have only to consider it as a shale brought into the state of basalt by fusion, without such further disturbance as to destroy its original stratification. Although both the neighbouring sandstone and alternat- ing shale which have undergone no change from the vicinity of the trap, contain shells, and that they occur in other places in the indurated strata, there are no marks of them in this bed of Lydian stone. They may nevertheless exist, although they escaped my observation. There is little doubt that tho instances of basalt containing shells which have so often been described, have been cases analogous to this : the observers, attending to the com- position rather than to the disposition of the rock, having easily been led into error from the perfect similarity of the indurated shale to fine grained basalt. Before terminating these remaiiis on siliceous schist I must notice a circumstance apparently of an analogous nature, but the rock being unconnected with any other strata capable of indicating its natural affinity, could not be referred to its proper place in the preceding description. It consists in some beds of quartz that occur in the hill of Greaulan near the northern part of Trotternish. Similar beds have been mentioned in describing Strath, and it is probable that the present owe their origin, like those, to sandstone strata thus al- tered by the influence of the superincumbent trap ; a change similar to that which occurs in the strata at Duntulm. There is but little to be said respecting the coal of Sky, the position of this mineral being commonly as obscure as its quantity is insignificant. Although a subject of much anxiety to the inhabitants and pro- prietors, it presents but little to reward the toil of a geologist. It is found in two distinct positions, in the one case included in trap, in the other interposed among the upper strata already described. SKY. GEOLOGY. COAL. 36l The first example to be mentioned partakes in some measure of both these positions, the stratum, Avhich is Uttle more than an inch in breadth, being interposed between common shale and siliceous schist, and the whole included in trap. It is to be seen between Loch Shga- chan and Conurdan. At Talisker a short and thin bed of coal accompanied by bituminous wood is found entangled in the trap rock, but so high in the cliff as to be scarcely within the reach of examination. On the farm of Scoribreck near Portree it is also found in several places among the trap, but always in an insignificant quantity, and scarcely amenable to investigation : larger masses similar to these occur on the shore at Camiskianevig and in Portree harbour. In these places it lies in irregular nests in the surrounding rock, varying from a quarter of an inch to a foot in thickness. The mass in Portree harbour has been wrought and abandoned, after furnishing, as it is reported, five or six hundred tons. It is said to have reposed on shale, while above, it was in contact with the trap, and to have extended from one foot to three in thickness ; but it is now invisible, having been overwhelmed by the fall of the superincumbent rocks. It is still however apparent, that it must have been cut off on both sides by the same mass of trap by which it was covered. The fragments still existing about the spot present much carbonized wood and pyrites, and are accompanied by pieces of bituminous shale. Similar, but more limited appearance^ of coal, are found near the head of Loch Grisornish, near Dunvegan, in Strathaird, and in other places ; but they are so insig- nificant in a topographic view and so uninteresting in an economical one, that I shall forbear to point out more of them ; particularly as the map will not afford an opportunity to future travellers of discovering them, and the names of the places where they occur defy all the powers of orthography. The appearances of coal among the stratified rocks 369, SKY. — CxEOLOGY. OVERLYING ROCKS. are still more trifling, while in most cases they are either overwhelmed or cut off by trap, so that they cannot be pm-sued for any continuous space. Their thickness rarely extends to a few inches, and they are found alternat- ing dispersedly with shale and sandstone over different parts of the surface of Trotternish. Among other places where they are visible I may name Loch Uig, and the waters of Leolt, Grocheard, and Grimset. Some attempts have been made to examine them in these places, but without attaining more information than is communicated by their casual display. The appearances are both too obscure and too rare to enable the nature and extent of the coal to be ascertained through such a country as this ; nor is it likely that any further expense will be bestowed on a pursuit so discouraging. It is probable that wherever this mineral appears, it is like that found among the corresponding strata in Egg, very thin and not persistent ; but it is impossible to speak with any decision respecting appearances so vague and unsatisfactory. All economical speculations on this subject are therefore superfluous, since nothing but a regular professional investigation could render the condition of this coal intelli- gible or determine its value ; but it may be remarked in concluding this cursoiy notice, that the connexion of the strata with the trap, such as it has already been represented, seems sufficient to destroy all hopes of success in working it as an object of profit. Having thus completed the history of the stratified rocks of Sky, I must proceed to the description of the unstratified, of which the general topographic extent has already been sketched. To assign the places and describe the characters of all the substances that come under this general title would be impossible ; so frequent are the changes, so intricate the mixtures of the several rocks, and so undefinable the sireater number of the varieties ranked SKY. GEOLOGY. OVERLYING ROCKS. 363 under it. Even if it were possible to define them, neither the geography of the country nor the nature of the map admit of accurate references. But it is still possible to make some distinctions, and it will be useful to make them even where they are unavoidably imperfect. With this view I have attempted to sketch both the characters and the places of the most important or remarkable, omitting others that were of less moment and that defy all arrangement. In conformity to the most general usage, I have throughout distinguished trap from syenite, even when speaking of them merely in their geological relations; although there is no geological distinction between the two divisions, which pass into each other and possess a common relation to the stratified rocks. For the same reason, porphyry, where it occurs, is also thus distinguished ; though more obviously a modification of the same substances that constitute trap and syenite, and in many places indicating its own rank as an accidental variety, by the frequent renewal and alternate absence of the only character by which it differs from the more simple rocks that constitute its base. Geologists will still consider these three divisions as appertaining to the trwp formation. Those who have been engaged in the investigation of this family of rocks must be sensible that the classi- fication above mentioned is imperfect, and founded on improper and insufficient characters. The defect will be principally felt in that division which is known most particularly by the name of trap, and includes many different substances associated by scarcely any bond but colour. The imperfections of nomenclature which result from the transition of different substances into each other, will continue to exist in a certain degree whatever care may hereafter be taken in separating the most remarkable individuals by appropriate names. I sliall not here attempt to remedy this defect, sensible of my 364 SKY. — GEOLOGY. OVERLYING ROCKS. incapacity for the task ; the Uttle I have to offer towards a new arrangement will be better reserved till the other islands similarly constituted have been examined. In the mean time it is impossible to proceed in the descrip- tion of Sky without giving some account of the different substances included under the form of trap, that will here fall under review; which may be done in the most brief manner. The first of these is claystone, resembling, in its leading characters and composition, the pale substance more generally known by this name, but differing in the colour, which presents various tints of grey or lead blue; that colour indicating a different state, and at times a different proportion, of the iron that enters into its composition. It occurs in different states of induration, and may occasionally be found passing into the clinkstone, and into the compact felspar of mineralogists ; the colour in these cases being neglected as an insufficient ground of distinction. It is necessary to distinguish this substance in its indurated states, from greenstone and from basalt, with both of which it is occasionally confounded. It will be found here to occur principally among the mountainous irregular masses, less abundantly among the stratified, although found in these and also in the form of intersecting veins. The next substance in the order of comparative sim- plicity is basalt, a rock as yet but ill defined, if indeed it be capable of strict definition : it will be found to occur almost exclusively among the stratified masses, but sometimes also occupies veins. I know not if the soft argillaceous substance which is the common base of the amygdaloids in this island will be admitted among the claystones, or whether British mineralogists are inclined to extend the name of wacko to it; since it differs in many particulars from that rock as it is known to the Germans. It differs equally from the claystones in some particulars, and may perhaps for the present be distinguished by the term of indurated SKY.- — GEOLOGY. OVERLYING llOCES. 36S clay : an objectionable one, it is true, but capable of serving a temporary purpose. This occurs only among" the stratified rocks, and, although generally amygdaloidal, is occasionally simple. The compound rock best known to mineralogists as a member of this family, is a mixture of felspar and hornblende, the former presenting two distinct charac- ters, the compact and the crystallized : the term of greenstone is sufficient to distinguish it, and it occurs here both in the mountain masses and among the strati- fied traps. To this compound rock may be added two more, one in which augit, and the other in which hypers- thene, occupies the place of hornblende ; both of which will hereafter be seen to hold conspicuous positions among the rocks of Sky.- In describing the several members of the unstratified rocks of which I have thus attempted to convey a general idea, I shall commence with the syenite, as there is no motive but that of convenience where there is no natural order. The general extent of this rock, and that of the moun- tains composed of it, have already come under review in the account of the face of the country. The first consideration, in a geological view, is the connexion which it has with the stratified rocks. On the shore near Broadford it is found for a considerable space distinctly incumbent on the limestone and shale of that series. It is in this place disposed in a flat bedded or laminar manner, and the junction is not attended with any alteration in the texture of the stratified rocks, or any disturbance of their ordinary regularity. It is found in the same manner lying on the same rocks, on the hills between Swishnish and Broadford, often very thin and disposed in patches of very limited extent. These are the only decided instances of its superposition and contact together, which I observed ; and when it is recollected that this tract is nearly the only one of stratified rock which occurs near to it, we must not be 4 366 SKY. GEOLOGY. OVERLYING HOCKS. surprised that the contact is not oftener to be seen. It may possibly be found in a similar position at Loch Sli- gachan, but in that place I observed only a junction of another kind. This consists of a bed of white sandstone found at a considerable elevation in the hill of Glamich, and apparently involved on all sides in the syenite. It may perhaps belong to the next modification, and in that case the sandstone bed is merely cut off on one side by the intrusion of the overlying rock. The next mode of junction is that where the syenite is found intersecting the body of the strata at some angle, while these terminate abruptly against it, being generally diverted to a certain degree from their natural position. The only instance I shall here quote occurs at Kilbride, and it has been alceady noticed in speaking of the limestone. It is needless to add to these any other examples to prove this double connexion between the stratified rocks and the syenite, as the same phenomena must have been witnessed, at least in the analogous rocks, by every geologist. Were it possible to gain access to the numerous junc- tions which must take place along the irregular line that in Strath separates the syenite from the limestone, many interesting appearances might probably be observed. It would in particular be desirable to know the precise cir- cumstances under which the marble occurs with relation to the syenite ; and whether, where this rock intersects, it produces different effects on the strata from those which occur where it merely overlies ; a circumstance very re- markable in the instances referred to on the Broad ford shore and at Kilbride. But there is no hope of such access, and we must remain content with knowing tliat the presence of syenite, like that of the common trap rocks, is often attended by a disturbance of the regularity of the adjoining strata, and by changes in their texture ; although in some instances no such changes take place. It is superfluous to dwell on that which must have SKY. GEOLOGY. OVERLYING ROCKS. 367 appeared during the examinntiou of the hmestone; namely; that the syenitic boundary is very irregular, and is accom- panied by detached portions of the calcareous rock. As the boundary of the syenite is found principally in the tract occupied by these strata, there is little to be said respecting its relations to the red sandstone ; since no opportunity offers of investigating these. The junction may possibly be found near Loch Sligachan, where that rock occurs ; and it is equally probable that it exists somewhere in the hills near the southern boundary of the limestone, since the syenite appears there to cover the line where the one set of strata succeeds to the other. I had not the good fortune to find it, the hills being much covered with soil and vegetation ; but there is no reason to expect any appearances different from those which happen in the case of analogous junctions, or from those already enumerated as occurring in the superior strata. It is now necessary to inquire into the connexion of the syenite with the other luistratified substances. As all these appear to bear a common relation to the strati- fied rocks, so they seem to possess a community of position and connexion among each other. In some instances there is a mere gradation ; the exclusion of one of the component parts giving rise to a new rock, which in return receiving an addition of some other material, becomes a third ; no variation of the great features taking place except that which arises from different degrees of durability, or from those changes of the bedded to the amorphous, or to the columnar forms, which equally occur where there is no change of substance. In other cases there is a decided line of separation, at times con- nected with a considerable change of composition, at others marked by that change of colour arising from the state or proportions of the iron which, though strictly speaking a change of composition also, is not a radical or important one. In these latter cases the rocks seem 36s SKY. — GEOLOGY. OVERLYINO ROCKS. to be placed in a disorderly manner, or are mixed together in a kind of lateral alternation. In this way, common greenstone, amygdaloidal claystone, common pale syenite, micaceous syenite, and simple blue claystone, will be found irregularly recurring throughout the whole group ; which in the map is marked by one colour only, since any topographic distinction of these variations was impos- sible. It may nevertheless be added, that syenite under different aspects is by far the predominant rock through- out this region. The hill of Glamich may be quoted as an example of these transitions and mixtures ; since it is unnecessary to accumulate instances where few will be inclined to examine them. They are however not unfrequent in that part of the island which is the common boundary of the syenitic mountainous region and the lower country of hilly or of stratified trap ; and they may very conveniently be examined at Loch Sligachan, as well as on the shores of the eastern Loch Eynort and of the sound of Scalpa. A question will naturally arise here ; namely, whether there is any difference of age between the several rocks of the unstratified division; whether for example the syenite is of prior or posterior origin to the ordinary trap rocks or to the hypersthene rock of the CuchuUin. If that which is just related respecting the interchanges of the two former be correct, there is no reason to imagine any such differences to exist. Still however, certain por- tions are to be seen which appear posterior to the main body of stratified trap, and consequently to the syenite ; the reasons for which opinion will be better introduced when these shall hereafter come under review. If there be any such difference between the syenite and the rock of the Cuchullin there appears no great prospect of discovering it. Although the former is found within a short distance of the latter, the intermediate space scarcely admits of the necessary examination, nor can the connexion be traced more circuitously through the intervention of the SKY. GEOLOGY. OVERLYING ROCKS. 369 common stratified trap, since the same difficulty occurs in attempting to connect it with that mountain mass. It is true, that while the main body of the syenite is found reposing on the hmestone, the hypersthene rock of the Cuchullin hes on the red sandstone at the only place where its junction with the stratified rock is visible. It is thus apparently connected with an older rock ; but if the unstratified rocks are throughout of a later date than the stratified, of which the evidence appears unquestionable, this circumstance must be considered as accidental and as incapable of proving any thing respecting their relative periods of formation.* * From laying too much stress on these connexions, and from theoretic views of the nature of the unstratified rocks of this family, have arisen distinctions which are often merely nominal, of traps of one or of another age, of first, second, third, and newesX, formations. The same mass will often possess the characters of all these, since it will in one place be found incumbent on the latest, in another on the most ancient rocks- I know not indeed that any certain marks of distinction can be pointed out among the several traps. In the greater number of instances at least which have fallen under my examination, such a relation between an unstratified rock, occupying the irregular and uncertain position which trap does, and those regular strata which maintain a constant order of succession, is by no means a criterion from which to judge of its relative order with regard to these. The aid of a diagram is perhaps required to render this statement intelligible to those who have not examined the rocks. The same mass of trap will for ex- ample be found in one place incumbent on clay slate, in another on red sandstone, in a third on limestone, in a fourth on the uppermost secondary strata. In such a case, when the separate portions are either not all acces- sible, or when they lie far distant and interruptedly, we might be easily led to conclude that they were so many distinct deposits, and thus apply to them terms derived from the particular beds with which they were found immediately in contact. A more intimate acquaintance with such masses, and with the general nature of trap, is required to correct these erroneous conclusions, and the accompanyingf sketches will explain that which actually occurs in nature, and of which, if I mistake not, instances are to be found in many situations in Scotland. Cases, doubtless, exist where a real distinction of periods in trap rocks can be proved; but t Plate XViri. fig. 5, 6. VOL. I. B B 370 SKY. — GEOLOGY. OVERLYING ROCKS. The only other circumstance which can at all be sup- posed connected with the question of relative antiquity between the syenite and hypersthene rock, is the occur- rence of veins of the former substance traversing the latter, an example of which is found in the valley of Coruisk. If this vein could be traced to the mass of syenite it might be held a sufficient ground of judgment, but, under the present circumstances, it is incapable of affiarding any assistance in solving the difficulty. Before terminating; this account of the transitions of the syenite, I may recall to the reader's mind the small mass of porphyry similar to that of Rasay, which is found on the point of Aird Bhornis opposite to that island^ and which, after the account of this rock formerly given, it will be unnecessary further to notice. The basis of the syenite is a substance which has gene- rally been received as compact felspar. In its softest state it may be considered as a claystone, since it offers no differences of character, while in a state of somewhat greater induration it becomes a clinkstone, and when more hardened is known by the name of compact felspar. As specimens occur here in the simple state, they must be considered mineralogically as examples of these different substances; although in a geological sense they cannot without troublesome circumlocution be described under any but the general term of syenite already adopted. The colour of the base varies from ochrey yellow and obscure flesh colour to grey : it is often cavernous, the cavities being filled with a ferruginous clay. In some situations it contains crystals of felspar, either of the same or of a different colour, and thus forms various kinds of porphyry. The predominant variety however is an aggregate of felspar and hornblende, in which the hornblende generally bears a very small proportion to they rest on more satisfactory evidence than that produced by the apparent or even real superposition of an unstratified above a stratified rock. SKY. — GEOLOGY. OVERLYING ROCKS. 371 the other ingredient: the porphyritic character is some- times superadded to this mixture ; while in some rare instances quartz enters into the composition, and it then borders upon syenitic granite. More rarely still it contains mica, and in this case it cannot be distinguished from those granites which contain crystals of hornblende super- added to the usual threefold mixture of quartz, felspar and mica. Under such circumstances it is conceivable that specimens should exist without hornblende, since even in those I have described, it is sometimes very thinly scattered through the mass. In such a case, should it occur, mineralogy, unassisted by geological observa- tion, would tend to mislead us respecting its position; and we are thus compelled to acknowledge, in geological description, the necessity of superadding to mineral cha- racters an accurate knowledge cf the connexions of the rocks respecting which we are reasoning.* It is there- fore from a geological knowledge of the position of the present rocks, that they are referred to the syenite divi- sion, since had the same specimens occurred in a mountain of granite and lying under micaceaus schist, they would have been ranked with the granites.f * This is far from being the only case in nature where mere mineral distinctions are insufficient to determine the geological situation of a rock. In the stratified rocks, both primary and secondary, these resem- blances are frequent; since it is often impossible to distinguish quartz rock from sandstone, the breccias which it contains from the more recent graywacke, ancient clay slate from recent, or, as I have shown in this account of Sky, primary from secondary limestones. The same rocks seem in some cases to have been repeated at different epochas, while in others they show variations which may perhaps be the results of posterior changes operating on tlie first deposits, rather than the conse- quences of original difl:'erences. f The character of this syenite gives rise to some conclusions that are not unimportant. At present, it is easily mistaken in hand specimens for a variety of those granites which are entirely sub- jacent to the older rocks and divested of any pretensions to the over- lyiog character. With a very slight change of composition it could not be distinguished. That such a change occurs in other situations «eenis 573 SKY. GEOLOGY. OVERLYING ROCKS. Two other varieties of this rock occur here, which may be mentioned, although possessing no pecuHar interest. In the one, chlorite forms a constituent part, and in the other a greenish compact steatite is intermixed with the felspar and hornblende, the total compound being not much unlike the porcelain granite of Cornwall. It is unnecessary to enter into a minute description of the substances that are connected with the syenite by transition. The general characters of these rocks are well proved by the observations of Mr. Von Buch in Norway, who has described granite lying on black conchiferous limestone. This granite is> according to that author, connected with porphyry, and there is no reason therefore to doubt that the instance quoted by him is analogous to this; although he has not entered into a full examination of its con- nexions. His overlying granite will therefore prove, like this, a mere variety, in a geological view, of the syenite and Tporphyiy formation ; another proof, if such were wanting, of the necessity of great caution in drawing geological inferences from the examination of mere specimens of rocks, and of the absolute necessity of tracing the actual connexions of all those rocks which are subject to similar variations of character. In the next place, this syenite may serve to prove, that in many other cases, the granites, which we have been accustomed to consider as prior in formation to the secondary strata, if not to the primary schists, may be often posterior to both: the opportunities for ascertaining their rela- tions being wanting; sometimes from the total absence of the secondary rocks in the places where they occur, at others from the impossibility of obtaining sufficient access to them to enable us to ascertain a point of great delicacy and difficulty, and in a third case perhaps from the demo- lition and disappearance of those portions which may have once been overlying, and have, as being the most limited and the most feebly sup- ported, been removed through a long course of time by the ordinary causes of waste. It is objected to the well known arguments in favour of the igneous origin of granite, that if it had been protruded from below in a state of fusion it should have flowed over the superincumbent strata: and the non- existence of this fact has been asserted. But the present case, as well as that of Mr. Von Buch, are in reality examples of it, as lar as this argument is concerned. It is not necessary that it should always occur. ■But I have no wish to enter the field of controversy. In the words of Erasmus, " Adeo invisae mihi sunt discordise ut Veritas etiam contentiosa displiceat." SKY. — GEOLOGY. OVERLYING ROCKS. 373 known, and the details of their variations are but httle instructive. The claystone in its several modificacions is commonly simple in composition ; being of ?, dark lead blue, which sometimes assumes a brighter hue, and occa- sionally passes through various tints to a pale whitish grey or ash colour. In many places it is porphyritic, the porphy- ries putting on a great variety of aspects, which differ ac-, cording to the colour of the base, the quality of the felspar that forms the crystals, their magnitude, and the density of their aggregation. Blaven offers a remarkable variety, in which solitary crystals of glassy felspar nearly two inches in length are sparingly disseminated through the ground. The beautiful variety consisting of pure white crystals in a ground of dark blue, which is found at Rasay, occurs also in Glamich. But it would be fruitless to describe more of these modifications. In the same hill it is found of an amygdaloidal texture, but, as far as I have examined, the cavities contain only crystallizations of epidote. The next great division of the unstratified rocks of Sky comprises the trap, using that term in the sense before defined. It is impossible however to draw a boundaiy, either in a geological or topographic view, between this and the syenite division already described ; the claystone modifications interfering with the whole alike, and being equally incapable of being distinguished in description in the one case as in the other ; while they serve at the same time to unite the two by transitions generally insensible. Under these circumstances it would require a volume to detail the whole of the appearances, nor would such a detail be productive of any corre- spondent instruction ; for which reasons I must be content with selecting such parts as present the greatest novelty, or are attended with circumstances of the most general interest. Those who may follow me will find a great deal that is not here described, although little that has not been examined. 374 SKY. GEOLOGY. OVERLYING ROCKS. The greater part of the tract westward of a line drawti from Loch Brittle to Loch Snizort, consists of these rocks disposed in a bedded or stratified manner, that dispo- sition beino- easily ascertained by the deep and prolonged sections which the great range of shore presents. In the interior of the country the stratified disposition ofteii ceases, and is replaced by momitainous masses, without any change of composition or any apparent cause for this great change of character. Even in those caseS where a decided difference is found between the mountain mass and the stratified one, as, for example, between the hypersthene rock of the Cuchullin and the ordinary trap of Ru an Dunan, it is equally impossible to determine the point where the one disposition ends and the other begins. Similar transitions are of frequent occurrence elsewhere ; and, although well known to geologists, no satisfactory explanation of them has yet been proposed. Of the numerous species of the trap family here exist- ing, basalt is among the most conspicuous, and it occurs almost every where, alternating in an irregular manner with all the other species or varieties. It is most fre- quently amorphous, displaying at the same time so great a variety both in its natural mode of breaking, in its external appearance on weathering, and in its texture and colour, as to form a great number of subordinate varieties much more remarkable in their natural situations than when broken into hand specimens. At Talisker and in other situations both on the western and eastern shores, it is found perfectly black, and of a very fine grain. Con- sidering the great extent of this rock it is but rarely columnar. The most beautiful and conspicuous collection of this nature at Great Brish Meal has been already men- tioned, and ranges of tolerably defined pillars are also to be seen in many places of this neighbourhood occupy- ing elevated situations in the cliffs. The next most conspicuous variety of trap in this part of Sky is amygdaloidal. I should perhaps in strictness SKY. GEOLOGY. OVERLYING ROCKS. 375 rather have defined this rock by its base than by its structure or accidents ; but mineralogical language has no means of distinguishing, not only the infinite difference, but the perpetual variation of the bases which contain these nodules of occasional minerals. It is sufficient to say, that the base varies from the hardness of basalt to nearly the softness of dry clay, and that the colours are black, blueish, brown, dark purple, and grey of dif- ferent tints, sometimes of a very pale tone. As these varieties often occupy different strata, and are variously intermixed with the solid kinds already described, the strata, when viewed in the cliffs, often seem to possess a diversity of composition which, when examined into, proves fallacious. The nodules imbedded in these amyg- daloids are very various, few of all the substances usually met with in the trap rocks being wanting in some part or other of Sky. The zeolites are the most conspicuous, since most of the species are found occupying these cavi' ties, and often in forms so important as to require a separate consideration in the description of individual minerals. Calcareous spar, chlorite, steatite, quartz, chert, chal- cedony, and prehnite, occur in other varieties; among which the two latter are most rare. At Talisker, mica is to be observed in some of them, a substance among the least common ; and in the vicinity of Scavig, epidote is an ingredient, the rock resembling precisely the speci- mens from Caer Caradoc. Many varieties of greenstone are found among the strata in different parts of the island; but they are far less common than the simpler rocks. In some instances the crystallization of the hornblende is very perfect. Basaltic porphyries occur also in different places, but, hke the greenstones, they are much inferior in quantity to the uniformly basaltic substances. The felspar is sometimes glassy, at other times opake, and the com- pound occasionally forms beautiful specimens. Wacke is I believe unknown in this island, although some of 376 SKY. — GEOLOGY. OVERLYING ROCKS. the more earthy amygdaloids have been sometimes de- sighated by this term. The substance known by the name of trap tuff, which I have, for reasons elsewhere assigned, called trap con- glomerate, is the last of the varieties which come under this general denomination : no more can indeed be enumerated, since the terms applied to the several members of this family are exhausted. This also occurs every where, and is generally intermixed with the other varieties. No example however vras observed of that variety pontaining rounded nodules and foreign substances which occurs in Canna ; the conglomerate in Sky always appearing to consist of a loose mass of angular frag-, ments of gravel and sand, easily mouldering to dust and soil. It is necessary to add to these, two substances, which although not appertaining to this family, are often found united with it, and rarely, if ever, in any other situation. These are iron-clay, and a particular sort of jasper. They occur separately or together in different places, but are ^ery conspicuous at Talisker. They are extremely irregular in their positions, and discontinuous in theiv lateral extent. The iron-clay is the most abundant, and forms considerable beds in the cliffs about Talisker, and along that coast as far as Loch Brittle. It is of various colours, red, purple, blue, and grey ; these being often very lively, and giving to the cliffs the appearance of having undergone the process of calcination. The jasper is rare. I have used this term because I know of no other by which the substance in question can so well be charac- terized. It is yellow or brown, with a lustre approaching to the resinous, and is well known as a product of St. Helena. The specimens of Sky differ in no respect from those of that island, which have sometimes, but improperly, been called pitch-stones. That they are not such, if proof were necessary, would be sufficiently proved here by the regular gradation whicli they undergo into clay \ SKV. GEOLOGY. OVERLYING ROCKS. 377. appearing indeed to be portions of clay which have undergone changes, in consequence of their vicinity to the basalt, resembling those which sandstones experience in similar situations.* ■ The succession of these several substances is often found in the same place, but their order can never be determined, as, from the cliffs rising to a height of 500 feet or more, they are so far out of reach as to prevent us from forming an accurate judgment respecting the individual parts. It is only by examining the fallen specimens that the varieties in any spot can be ascertained. They seem more numerous from Loch Bracadale to Loch Brittle than elsewhere, but possibly this may arise from the greater facility experienced in examinino- this line of the coast. The number of strata seem to vary from eight or nine, to twelve, fifteen, or even more ; but it is not easy to define their boundaries at the distance from which they must be viewed. The manner in which the several beds decompose often adds a very remarkable feature to the cliffs : some become scoriform, others moulder into large cavernous shapes, while a third set fall to powder; and these various appearances com- bined with the colours of the iron clay, give to the whole that aspect of having undergone the action of fire "Vvhich strikes a common observer even more forcibly than a geologist. Besides these, siliceous schists of various kinds occur among the beds of stratified trap, occasionally extending for a considerable space. It is by them indeed that the divisions of the strata appear often to be determined, and they perhaps offer the clue to explain this disposition. It has been shown in de- * I have since received similar specimens from Guadaloupe, where they occur among the lavas of that island, adding one more to the numerous analogies already existing between the volcanic rocks and those of the trap family. 378 SKY. GEOLOGY. OVERLYING ROCKS. scribing the siliceous schists of Trotternish that they often resemble basalt in appearance, the difference being only marked by the slaty structure. It was also proved that they were argillaceous schists altered by the influence of the adjoining trap. It is easy to conceive that a further continuation or a greater degree of this influence would obliterate the structure also, and thus convert them into simple stratified basalts. To apply this reasoning to the western cliffs under review, it is only necessary to suppose that the original schistose strata possessed the variety of composition usual in similar cases, and that they have been fused in their places ; the different beds undergoing, in consequence, the various changes which produced the differences in the trap strata now visible, and the more infusible having been converted into the siliceous schists that still remain to mark their origin. There are many other cases of stratified trap to which this explanation will apply; and it is further easy to see that it offers a solution of the difficulty before stated respecting the connexion of that variety with the mountainous one.* With this general account I shall close the description of the great north-western portion of Sky, and proceed to the north-eastern part, which presents many interesting appearances. The trap already described, whether mountainous or stratified, affords no examples, except in the very few * The porphyry wliich accompanies the coal field of Campbelltown presents a structure very illustrative of this view. Through every part of the mass, fragments of schistose rocks may be observed, varying in dimensions and, in some cases, of considerable extent. It is not difficult to trace the gradual transition by which tliey pass into the shapeless mass that includes them, while they present those other striking indications of the action of fire wiiich I have described at full length in a paper on the Hill of Kiimoul published in the Geological Transactions. The mixture of schist and trap in this hill is obviously of a similar nature, and equally illustrates the present view. \ SKY. GLOLOGY. OVERLYING ROCKS. 379 instances formerly enumerated, of interference with the secondary rocks, these latter occupying a definite region separated from them by a boundary incapable of deep examination. But in many parts of Trotternish, and principally on the eastern shore, abundant and most interesting examples of this nature occur, exceeding in number and variety all those which have been hitherto enumerated in Scotland. The character of this trap is also different from that of the western shore. In the latter tract it generally presents a stratified appearance, one substance being succeeded by another, sufficiently different, although of the same family, to cause the line of separation to be visible even from a distance. But here the appearance of stratification does not take place, although the horizontal line which separates the strata from the incumbent trap presents a deceptive appearance of it ; while a tendency to the columnar structure is every where to be seen. This tendency is particularly marked at the northern ex- tremity of Trotternish, as well as on its western shore, and extends in a certain degree to the opposite pro- montory of Vaternish. In a few cases, the most remarkable of which have already been described, the columns attain considerable regularity ; yet they are never so perfect as in Staffa, nor are they horizontally jointed as in that island. In some places however the ranges are distinguished by a pecuhar feature, a whole series being cut through by one long extended horizontal joint as decided as if it had been made by a knife, while the ends of all the columns above and below it, remain continuous in adaptation and without any marks of displacement. It is unnecessary to describe the nature of all the rocks over this large space, but the general aspect of them is that of greenstone, varying in the fineness of the admixture, and sometimes assuming the appearance of basalt. Occasionally, amygdaloidal masses are also found, but as no useful information could be conveyed 4 380 SKY. — GEOLOGY. OVERLYING ROCKS. by those details, I shall only notice that variety which occurs in the eastern cliffs already described. It appears to be a mixture of compact felspar and augit, differing in some respects from that variety of the same rock which is the most conspicuous in Rum, since the felspar in this latter is generally of the crystallized or of the glassy kind. There is reason to believe that this rock is of much more frequent occurrence than has com- monly been supposed, and that it is often mistaken for common greenstone ; the difficulty of distinguishing be- tween hornblende and augit, when in a state of minute admixture with felspar, being very great, if not insuper- able. In the example now under review the investigation is more easy, from its presenting many . of those veins known by the name of contemporaneous, which graduate into the surrounding rock and contain large though ini' perfect crystals of the augit. There is also a certain facility in detecting the nature of the rock when fresh, which is lost in the specimens that have had time to dry. The finer varieties when thus broken are comparatively tender, with the aspect of serpentine, the felspar being of a decided green and the augit of a pitchy black. In a day or two this distinction vanishes, the whole acquiring great additional hardness and an uniform grey colour; in which case it often happens that neither of the con- stituent parts can be discerned with any degree of certainty.* * With others, I have had frequent occasion to notice the soft nature of many rocks and minerals when first taken from the earth, and the changes tliey undergo on drying, but the case of greenstone or of other rocks of the trap family so circumstanced hiis not, as far as I know, been remarked. I have observed a similar instance to tliis in Ijute, and do not imagine it to be uncommon. It is probably overlooked, only because the toughness of these rocks commonly renders the mineralo- gist satisfied with the first superficial fracture that he can obtain. There is no apparent reason wiiy the rocks of this family should not contain water, even admitting their igneous origin ; as it is evidently in a very loose ctate of combination, or it could not so readily be sepaj-ated by SKY. — GEOLOGY. OVERLYING ROCKS. 381 This rock may without inconvenience be desicrnated by the term augit rock, a name absolutely wanted if, as I have already said, it is found to constitute a principal member of the multifarious family of trap. It is inter- estino; to remark that the characters of the lavas and the traps are thus still further approximated, since the observations of mineralogists have recently proved that augit and not hornblende forms the dark part of these vol- canic products. One circumstance relating to the position of the trap is worthy of remark before proceeding to consider its interference with the stratified rocks. In some places the continuity of the uppermost incumbent stratum is broken ; a single patch of columnar rock being found lying on the strata detached from the surrounding parts.* This phenomenon assists in illustrating that much greater loss of substance which in other cases, as in that of Dun Can in Rasay, has left a single eminence of trap insulated on the surface of the subjacent rocks. The great tendency of this substance to decomposition, explains the mode in which the loss of masses so exten- sive takes place, without the necessity of having recourse to violent causes of denudation. Other similar instances have been noticed in different parts of this work, but I may here point out a very remarkable example on account of its accessible nature. It lies at the north Queen' s-ferry, the complete transition from trap to yellow clay being undisturbed ; the marks of the rude columns and of the spheroidal crusts by which they have succes- sively decomposed still existing in the clay, though now reduced to powder. mere exposure to the atmosphere. Tlie travelling apparatus to which a geologist is limited does not easily admit of the means requisite to ascer- tain the proportion of water on the spot, where alone it could be determined; and the delay of even a day or two is sufficient to dissi- pate it, in part or altogether. * Plate XVII. fi". o. 382 SKY. GEOLOGY. OVERLYING ROCKS. The interference of the trap with the strata presents, as I already remarked, every modification that has yet been described. Some of them require a few words, but the greater number will be sufficiently and even better illustrated by the drawings, which have been so selected as to contain the principal details of the whole line of disturbance ; the general aspect of larger portions of the coast beinsc R'iven in other sketches taken from a dis- cs o tance where the minor disturbances were invisible.* One of the objects is to show that there is no persistent parallel- ism between the trap and the stratified rocks, and that the occasional regularity of alternation is deceptive ; since by extending the examination we always arrive at some point where that regularity ceases. This fact has often been noticed on a smaller scale ; but there is here a display of the whole arrangement on a scale so magni- ficent and extensive, since it occupies many miles in length, and so free from all chance of error since the sections are as perfect as if made by art, that it would be unpardonable to pass it over. The instances of fracture, separation, displacement, flexure, and entanglement, are sufficiently visible in the drawings; those of irregularity in the stratified disposition of the trap, require a few w^ords. In one case,i- which occurs not far from Holme, there is a bed extending for a great way, surmounted by a parallel series of the secon- dary strata in contact with it ; but on a narrow inspection innumerable veins are seen branching into the strata in every possible direction, illustrating in a very perfect manner the origin of at least one order of veins. In a second case;]: three beds of trap can be traced in a parallel direction for a considerable space, separated by the regular strata, when suddenly the whole unite into :One mass. Had not this occurrence at length betrayed the true nature of these beds, there would have been no * Plate XVII. t Plate XVII. fig. 3. J Ibid. SKY. GEOLOGY. OVERLYING ROCKS. 383 hesitation, from a limited observation, in describing them as unquestionable instances of alternation. In the last case which I shall enumerate, one regular bed of trap may be traced for more than a mile, lying in a parallel and undisturbed continuity between the secondary rocks. On a sudden however it bends downwards so as to pass through the strata immediately in contact, and then con- tinues to hold its regular course for a space equally great, with a thickness and parallelism as unaltered as before.* I need make no commentary on these several facts since the conclusions that may be deduced from them have long been familiar to geologists. But I cannot terminate the account of this most extra- ordinary and interesting part of Sky, without pointing out that, of which the sketches already referred to will show the details.-f It is, that notwithstanding the entangled fragments of the strata, the columnar disposition of the sur- rounding trap is not affected. That disposition commences to the southward of tlie nameless cascade already men- tioned, and seems to be continued with a persistent regula- rity to Loch Staffin whether these fragments are present or not ; although they are actually more numerous and remarkable here than in any part of the whole line. Another portion of the trap of the eastern shore which appears worthy of description occurs at Sligachan. In many places, as I have already noticed, the mixture of the ordinary trap with the syenite is frequent, and it appears to take place chiefly near the northern boundary of the latter before this is thoroughly established. These mixtures can therefore be traced along the shores of the sound of Scalpa, the borders of Loch Eynort and of Loch Sligachan, and from the latter point to a short distance in the direction of Portree. In some cases there is a gradation from the best characterized greenstone to the most ordinary syenite, through various shades both of * Plate XVir. fig. 1. t Plate XVIL figs. 3, 6, 7, 9, 11, 12, 13, U. 384 SKY. — GEOLOGY. OVERLYING ROCKS. Colour and composition; while in others the separate sub- stances lie irregularly intermixed without gradation ; the contact of the two being such as not to indicate the relative priority or posteriority of either. The transition, where it exists, is formed by means of a blue compact felspar, which first replacing the yellow felspar of the syenite, is finally converted into greenstone or into augit rock by the acquisition of hornblende or augit. Among the remaining overlying masses of trap that seem worthy of a distinct notice is that which occurs near Swish- nish point, which, though not very extensive, affords an interesting and distinct section of its structure and of its connexions with the subjacent strata, as the accompanying- drawing will more fully explain.* Connected with it is one large process or vein an hundred feet or more in thickness, cutting through the strata and lost in the sea, affording an example of the double connexion which trap has with the stratified rocks. At some little distance frqm this, numerous smaller vertical veins descend in the same manner, cutting through the subjacent strata. This fact illustrates the origin of trap veins, at least in cei'tain cases, even more distinctly than the appearances just mentioned on the eastern coast. It is probable that they are in most instances connected with a principal mass, even where we have not the means of tracing them to their sources ; while it may happen in some, that the masses with which they have once been con- nected, have disappeared in the progress of time, leaving behind those parts only which were protected by the sur- rounding rocks. The ultimate removal of the overlying trap of Swishnish, a circumstance far from improbable, would thus leave the veins in question remaining independent, and thus perhaps induce future geologists to attribute to a protrusion from below that which may equally have entered from above; though it is not necessary, even * riate XIV. fii'. 5. SKY. — GEOLOGY. HYPERSTHENE ROCK. 385 for the igneous theoiy of this rock, that every mass or vein should have originated in the former manner. Although the same perfect exposure cannot be obtained^ there is reason to think that tlie trap of Strathaird is similar to this, and is equally the origin of the numerous veins which there intersect the strata. There is also some reason for supposing that these masses are of more recent origin than those which form the bulk of the island, since the latter do not send forth any such veins, but are on the contrary intersected by veins of a date more recent than themselves. These probably originate in masses now removed, or concealed from view ; and as such masses must necessarily, like the veins, be of later date than the rocks in question, it is a natural consequence that there are in Sky two distinct formations of trap. It is not improbable that the rock of Swishnish and Strathaird belongs to the second of these; a question which can only be decided when the veins of Strathaird that intersect the stratified rocks shall also be traced into the rock of Blaven or the other neighbouring mountains. Such a connexion may accidentally be dis- covered, but the nature of the country is such as scarcely to admit of a regular investigation of this point. I have remarked in the general description that the Cuchullin mountains are principally formed of a compound to which I have given the name of hypersthene rock. For the sake of the topography it would have been desirable to define the region occupied by this rock ; although it is of little consequence in a geological view, since its rela- tions are not required for the purpose of comparing strata or ascertaining their connexions, as if it were a stratified substance : ii is little more than a question respecting the proportions of one or of another member of the trap family. The difficulty of ascertaining its extent arises from the thoroughly inaccessible nature of the eastern declivity of this ridge, and from the almost insuperable obstacles VOL. I. C C 386 SKY. — GEOLOGY. HYPERSTIIENE ROCK. which impede its examination in many other parts ; a stormy diniate added to the distance from human habita- tions and the difficulty of access, opposing all investi- gation. Although I have only named the Cuchullin ridge, this rock is not thus limited, since it extends to the moun- tain boundary of the eastern side of Loch Coruisk, as will be seen in the accompanying map. There is even reason to suppose that it forms part of Blaven ; an opinion founded on the similarity of its craggy outline and the remarkable permanence and nakedness of its rocks, which I have never yet had an opportunity of examining. Although it forms the principal and fundamental rock of these mountains, it is not the only substance present. Blue felspar porphyry of different aspects, blue claystone, and common greenstone are also to be seen in different places : if we should judge from the fragments of these rocks that are scattered about, their extent would be supposed considerable. But I believe this is one of the fallacies that not uncommonly arise from trusting to the examination of detached fragments. No extent of such rocks can any where be found in situ, but veins of them may be seen in many places, whence it is natural to con- clude that they are the origin of the fragments in question, being from their inferior hardness more subject to waste than the including rock. There is nothing more remarkable in the hypersthene rock than its uncommon power in resisting the effects of time and weather ; the consequence of which has already been mentioned in the general account of the disposition and features of the island. That durability is exhibited not less remarkably in the condition of the rock on the faces of the mountains, than in the spiry and rugged forms of the summits already mentioned. Detached frag- ments of it are indeed found, but as they have fallen so they lie, unchanged, no accumulations of sand or gravel from their decomposition being found in the valley ; the small and partial deposits of clay that here exist having SKY. — GEOLOGY. HYPERSTHENE ROCK. 387 evidently resulted from the wasting of the soft veins, not from that of the fundamental rock. It is partly owing to this cause, partly to the rapid declivity of the mountains and to the absence of shelves and fissures, that so little vegetation is found in this place. A patch of grass may occasionally be seen where some favourable circumstance has permitted a little gravel to accumulate, but in general it presents one continuous brown surface, not even di- versified by a lichen. The roughness of the surface of this rock is 'scarcely less remarkabla than its nakedness, being comparable to nothing more properly than to a coarse rasp ; in conse- quence of which it is easy to walk or run over those steep declivities which would otherwise be impracticable. This roughness arises from the crystals of hypersthene that project from the compound in consequence of their supe- rior durability to the felspar ; undergoing no waste, and often indeed gaining rather than losing brilliancy by the exposure. If the overlying position of this rock, and its connexion with the other members of the trap family, did not deter- mine its place among these, we should, from its external features and disposition, assign it one with granite, so much does it resemble the rocks of this tribe. It is dis- posed in huge beds with a convex surface, separated from each other, not so much by the actual presence as by the indications of future fissures : although, in a few instances these have become sufficiently complete to allow masses to be detached and rolled from their places. Besides the more extended convex beds, large spheroidal concretions are of frequent occurrence ; being in some cases so protuberant that half the solid is visible, and their diameters reaching to 50 or even to 100 feet. These are the only modifi- cations of external form visible in this rock, which in no case presents either the flat stratified disposition or the tendency to vertical fracture so common in the members of the trap family ; being in every respect, except that 388 SKY. — GEOLOGY. HYPERSTHENE ROCK. of mineral structure, entirely different from the ordinary varieties of this substance. Its granitic aspect is still further displayed in a most striking manner in the spiry forms of the summits, in their hard serrated outline, and their overhanging masses, by which they are rendered inaccessible even to the stags and the wild goats that roam over this region of solitude and rocks. To this is owing their highly picturesque aspect, which bears a striking resemblance to that of the granite hills of Arran, or the more stupendous granitic masses of the Alps. It offers one instance, among a thousand otl^ers, of the little dependence to be placed on the characters of the outline in determining the nature of mountains ; and shows how easily geologists, who have assumed the certainty of such a criterion and used it in their investigations, have been led to deceive themselves, and have contributed to mis- lead their readers. The appearance produced by the fallen fragments is very remarkable, and cannot fail to strike a visitor on his first entrance into the valley of Coruisk. The interval between the borders of the lake and the side of Garsven is strewed with them ; the whole, of what- ever size, lying on the surface in a state of uniform freshness and integrity, unattended by a single plant or atom of soil, as if they had all but recently fallen in a single shower. The mode in which they lie is no less remarkable. The bottom of the valley is covered with rocky eminences, of which the summits are not only bare but often very narrow, while their declivities are always steep and sometimes perpendicular. Upon these rocks the fragments lie just as on the more level ground, and in positions so extraordinary that it is scarcely possible to conceive how they have risen so high after the rebound, or how they have remained balanced on the very verge of a precipice. One, weighing about ten tons, has become a rocking stone ; another, of not less than fifty, stands on the narrow edge of a rock an hundred feet higher than SKY. — GEOLOGY. HYPERSTHENTE ROCK. 389 that ground below which must first have met it in the descent. Possibly the presence of snow at the time of the fall may assist in explaining this remarkable ap- pearance. Although scarcely subject to decomposition, the hyper- stl\ene rock shows an occasional tendency to separate in crusts capable of being easily detached, and no wise altered in hardness or integrity. In this respect it resembles some granites, as well as some of the more common members of the trap family. This rock presents a few varieties of composition, the simplest being predominant and the more com- pound rare. The most compounded variety consists of hypersthene, glassy felspar, common felspar, and horn- blende, and the next differs in the omission of the horn- blende. I ought perhaps to add to these minerals oxidulous iron, since it is at times so equally diffused among the other ingredients as to form an integrant part of the rock. This substance indeed often occurs even in the simplest variety, being almost always crystallized in accumulated tetraedrons ; while it acquires by exposure a black polished face, being, like the hypersthene, unchangeable, and adding to that roughness which characterizes the weathered sur- faces. The simplest varieties consist of a mixture of hypersthene with compact greenish felspar, or with felspar of a crystalline and somewhat glassy aspect. These, from the varying magnitude of the constituent parts, are subject to considerable variety of aspect, the crystals or concre- tions of hypersthene being in some cases half an inch in length, in others not exceeding in size a pin's point. In this latter case the rock cannot easily be distinguished from a comm^on greenstone, where the fracture is fresh ; but the distinction is in general made with great facility on the weathered surface, in consequence of the persist- ence of the hypersthene. In a few instances the felspar is of a dark purplish hue like that of Labrador, and the appearance of the fresh rock is then still more deceiving, although the same natural analysis almost always discovers 390 SKY. — GEOLOGY. HYPERSTHENE ROCK. its real nature. These several varieties are all irregularly mixed, occurring in close contact in the same continuous mass, occasionally passing into each other, and often dis- posed in such a tortuous manner as would arise from disturbing a mixture of diiferent tenacious fluids. One rare variety yet remains, especially deserving of notice. In this the crystals of hypersthene are in small compressed prisms, disposed with their flat surfaces parallel to each other and to the general plane of the mass, as mica is in gneiss, and producing the same fissile tendency. Like the mica in the trap of Kerrera and Seil, it may be sup- posed to throw doubts on the opinion that the fissile property of gneiss, or even of micaceous schist, is the result of mechanical disposition. As this rock has never hitherto been observed, or else has been confounded with the common varieties of trap, it will be useful to mineralogists to know that it also occurs at Airdnamurchan, and that it forms the supposed greenstone of that promontory. In this place also it contains those veins in which the large concretions of hypersthene are found. It is probable that the rock which produces the same mineral in Labrador is of a similar composition ; nor is it unlikely that it will here- after be found in many places where it has yet been unnoticed, or, as in Airdnamurchan, confounded with other substances. The hypersthene rock of the Cuchulhn is traversed by veins of different kinds, which it will be more useful to describe here than in the section to which the considera- tion of trap veins is referred. The first variety of these to be noticed, contains the same ingredients as the including rock, with some occa- sional additions ; but the hypersthene always forms the most conspicuous part. They are generally thin and not persistent, and at the same time pass insensibly into the surrounding mass. But the most numerous class consists of a blueish grey compact felspar approaching to claystone, very SKY. GEOLOGY. HYPERSTHENE ROCK. 391 persistent, and intersecting in a decided manner the rock, which occasionally contains marks of fracture and displacement. The veins are of various sizes, most com- monly not exceeding one or two feet in breadth, some- times attaining a much larger dimension, and frequently descending to that of a few inches or even less, while they also ramify into minute branches. They are always conspicuous, from the contrast of their white and weathered surfaces with the black colour of the hypersthene rock. In one of them is presented a beautiful example of the entanglement of the including rock, the fractured and displaced parts admitting of the most accurate readapta- tion ; and as it could not be fully understood by description it is represented in an accompanying drawing.* In some places, large veins are seen, composed of a very compact hard substance, as sonorous as cast iron. Detached fragments of these are conspicuously strewed on the borders of the Lake Coruisk, being generally honey- combed into deep cavities, but without any mark of rusting or decomposition. The rock is of a pale grey colour and fine grain, with an unusually high specific gravity, and appears to be formed of an intimate mixture of pale augit and compact felspar. Fragments of similar veins are also found studded with protuberant bodies resembling large pedunculated fungi. Very rarely there occur thin veins of a black substance rather resembling Lydian stone than any variety of basalt, perhaps analogous to pitchstone, and scarcely distinguish- able, by the eye alone, from jet. Veins of common grey syenite, not to be distinguished from that which forms the mountains of the middle district, are equally rare; whether ramifications from this mass is a question that has already been considered. Having thus described as far as appears necessary the overlying trap rocks of Sky, I must now inquire into the apparent effect which they have had in displacing * PI. XXVI. fig. 4. 392 SKY. GEOLOGY. OVERLYING ROCKS. or overwhelming the regular stratified rocks.* In enter- ing on this subject I must necessarily refer again, as on former occasions, to the description of some islands unavoidably placed after Sky in order, namely, Scalpa, Lunga, and Pabba, as well as to Rasay, formerly de- scribed. A line may be drawn in a south-westerly direction from the mainland through the Croulin isles, Scalpa and Sky, to Soa and Rum, marking the course of an elevated set of strata of red sandstone. On the south-eastern side't" the boundary of these strata is marked by their contact with the limestone of Scalpa, while on the north-western it is neither so definite nor so regular, but may be traced as far as the southern part of Rasay on one side, and the north-west angle of Rum on the other, beyond which there is no land present to indicate its place. Of the difficulty which exists in assigning the relation of this portion to the lime- stone eastward of it, I have spoken in the account of Scalpa, to which I must here refer. Whatever that relation may be, it is reasonable to suppose that since these strata bear an accurate resemblance to those of Sleat in direction, in composition, and in relation to the neigh- bouring rocks, they belong to an equally continuous and regular deposit. It has been seen that those strata maintain an even course till they meet the sea and dis- appear ; and that there is here no rock of the trap family to obscure or disturb them, except the syenite of Ben na Charn, the effect of which will confirm the view of the cause now to be assigned for the interruption of the second or north-western line of red sandstone which may be called the Scalpa line. If now an attempt be made to trace this line, we find it disappear on the eastern coast of Sky, nor does it again come into view until we reach Loch Scavig in this direction, where it is found covered by the trap of the Cuchullin hills ; an indication, though * Plate XIV. fig. 1. — Plate XV. f See ihc Map ul'Sky and also the general Map. SKY. — GEOLOGY. OYEllLYINC ROCKS. 393 a slight one, of its existence below that rock, and of its prolongation beyond the boundaries of the island. Rum and Soa must be considered as belonging to this line ; the former presenting a deficiency caused by the superincumbent trap, while in the latter, where that rock does not exist, the beds are regularly persistent throughout. On this line therefore, all that portion of the strata of Scalpa which should be found in Sky are missing, with the exception of the very small portion at Scavig above mentioned, and here the chief mass of the Sky mountains lies. If v/e examine any other portion of the strata we shall find similar although not equal deficiencies, attended by consequent irregularities; all of thera, doubtless, equally caused by the trap rocks, the effects of which seem to consist in the overwhelming of some of the strata and the displacement of others ; the whole being on a scale so large and distinct as to leave no doubt respecting their nature, and producing a connected train of appearances that can- not be traced in any other place with which I am acquainted. The structure of Arran, in some respects similar, is less obvious, either to the sight or to that species of induction here used ; and the phenomena now thus brought under one general view, will perhaps serve hereafter to illustrate other analogous tracts where no industry can draw together the same collective proofs. I shall not attempt to point out the revolutions that must have taken place in these parts of the earth's surface before such effects could have been produced ; still less to inquire into causes, in a work intended as a simple record of the physical structure of the places examined, as far as it is possible to give such a record its due value without a certain proportion of theoretic connexion. While the changes are as obvious as their magnitude is striking, it is evident that they have been produced long after the greater part of the materials here forming the surface of the earth had assumed their regular distribution. I have reserved to the last place the consideration of the 39^^ SKY. GEOLOGY. TRAP VEINS. trap veins which are found in such abundance throughout this island, because, on account of their number and the interesting circumstances which attend them, their history- would have led to a perpetual interruption of that description which required to be unbroken. I have here, as on other occasions, applied to these veins the general term trap, for the reasons assigned in speaking of the rocks of this class, namely, because they vary in composition ; although basalt is perhaps the prevalent substance in them. The order allotted for them in this description is also that which they hold in nature, since they traverse every rock that lies in their way, from the most ancient to the most recent; seldom suffering any change either of direction or composition in this varying course. As the same vein is therefore found to pass indiscriminately through rocks of all ages, it is plain that its association with these can afford no register of the period of its formation. If there were ten different periods in which these veins had been formed, we must be contented in most cases to prove but one, namely, a period posterior to that of the latest stra- tified substance through which they pass. It is only where they interfere with each other that a register more extensive can be found. I have always sought for such examples wherever these veins abound, and, among other places, in Sky, but have never yet traced more than two distinct sets. This number I have also observed in Rum. Both are perfectly visible near Loch Scavig and at Strathaird ; and the examples are unquestionable, since those of one period hold their course through the other in every direction, with the same pertinacity and distinct- ness as the first do through the fundamental rocks. We have no means of knowing what distance of time has intervened between these veins. The angle of the courses of both kinds with the horizon is various, but in a very considerable proportion it is vertical or nearly so. Trap veins, apparently of the first set, are of frequent oc- currence in the gneiss of Sleat, and they also abound in the SKY. GEOLOGY. TRAP VEINS. 393 sandstone at Loch Eishort, where they are of considerable size. Here they are readily traced through all the beds as far as the most distant surface of the limestone. The second set traverse not only the mountain trap but the veins last named, and are therefore of a posterior date to both. They are much smaller, often indeed not exceeding half an inch in breadth, and are composed of an extremely fine and hard black basalt. Even where they exist, they are less abundant than the first, nor are they found in nearly so many situations. They are frequently to be observed pass- ing through the rock at Coruisk, and through the larger veins of Garsven, in the neighbourhood of which latter in particular, they abound. Their compactness and lustre are frequently so great that they approach in appearance to that pitchstone which forms the basis of the beautiful columnar porphyry of Egg. In addition to this feature they are strongly distinguished from the trap veins that traverse the sandstone, by their intimate and almost inse- parable union with the body of the rocks in which they lie; whereas the latter are separated with the greatest ease. The veins which are found in the stratified trap are not very abundant, but may be seen distinctly among other places on the western shore ; traversing the lofty cliffs in various, but generally perpendicular directions, of a very large size, and frequently of a stratified structure. They do not resemble in composition those of the second rank, just mentioned. As no useful purpose could be served by describing all the individual examples that abound in this island, I shall pass over many which offer no interesting features in themselves, and are of no value in geological science ; limiting myself to a few which present appearances the most worthy of note. Those of Strathaird are among the first that deserve notice, on account of their extraordinary number, and of some particular appearances by which they are distin- 596 SKY. — GEOLOGY. TRAP VEINS. guished. I have already slightly mentioned them in the general description of this coast, but must now be more par- ticular, and, to give an idea of their general appearance, have subjoined what must rather be considered as a plan than a drawing, since the extent and nature of the subject admit of nothing else.* I formerly noticed their extraor- dinaiy numbers, and may now add that in consequence of their frequency, they in some places nearly equal, when collectively measured, the stratified rock through which they pass. Six or eight sometimes occur in the space of fifty yards, their collective dimensions being apparently not less than sixty or seventy feet. This remark is not mere matter of curiosity, since, as will presently be seen, it leads to geological inferences not unworthy of regard. Their direction is almost invariably either vertical or slightly inclined from the perpendicular, and they present therefore a nearly regular parallelism along the coast. Each vein is of equal size throughout its visible course, and without rami- fications ; and although they vary from five feet to twenty in breadth, they more commonly do not exceed ten. It is well known that the permanence of trap veins is some- times less, at others greater than that of the surrounding rocks. Hence they sometimes project like walls, while at others their ruin produces fissures or caves. This latter effect has taken place here, marking their great tendency to decomposition, since the including rocks do not seem to be of a very durable nature. The depth to which they have been excavated is often very considerable : in the case of the Spar cave, including the external fissure, it cannot be less than 250 feet. In consequence of this wasting, the intermediate cliffs which remain, have, as I have noticed in the general description, the appearance of the ends of walls ; and as they sometimes yield and fall away behind, they present in such cases the appear- ance of insulated square pillars of masonry ; the resemblance * Plate XVI. %. 1. SKY. — GEOLOGY. TRAP VEINS. 397 being rendered perfect by the channelled marks of the strata formerly described. These veins are often stratified, or more properly speaking, laminated in the direction of their length. They are generally formed of a blueish black basalt : at times they are porphyritic, or vary in other ways which it is unnecessary to describe. I observed in one of them nodules of prehnite, the only occasion on which I have found that mineral in veins of trap. In another a second vein is seen, holding a sei-pentine course through the first in a somewhat parallel direction, and readily distinguished by being formed of a much more black, durable and compact basalt : it is represented in the accompanying sketch.* The peculiar circumstances and extraordinary number of these veins induced me to follow them where they should be expected to reappear. As a preliminary to this attempt it would have been desirable to find their true bearings ; but the want of parallelism in their courses, and the devia- tions from a rectilinear direction, rendered this attempt abortive. They appear however to possess an average com- mon bearing, crossing the line of the coast obliquely, with a general tendency to the northward of west. In at- tempting to trace them in this direction they disappear in the superincumbent trap, none being found on the western side of the promontory. Hence it is probable that they are all branches from that mass, a circumstance in some measure confirmed by the appearances at Swishnish point formerly described. On examining the opposed shore of Sleat, in which trap veins also occur they are found sparingly dispersed towards the point of that promontory, and still more rarely to the northward of Ord. But at an intermediate part of this coast, and principally in the vicinity of Tarskavig, they are very numerous, and nearly as frequent for a short space as on the shore of Strathaird. Whether or not these are * Plate XVUI. tk. 1. 398 SKY. — GEOLOGY. TRAP VEINS. to be considered as prolongations of the former, it is impossible to determine ; although they are probably the same. The courses of trap veins are frequently attended by disturbances in the including strata, but the present instance affords a remarkable exception. Although so numerous in Strathaird, no disturbance occurs in the sand- stone beds ; their regularity being the same in the upper parts of the coast where the veins abound, as near its southern extremity where they are nearly altogether absent. Perhaps their absence at this place may be considered as strengthening the notion that they originate in the superincumbent trap, which does not extend towards the end of the promontory. Although no particular in- duration or change of texture occurs immediately at the contact of the veins with the strata, yet it must be remembered that the whole mass is of a hard quality where the veins abound, and of the usual soft texture where they are wanting. Before quitting this subject it is necessary to point out one extraordinary effect that must have resulted from the intrusion of these veins. Whatever proportion, col- lectively taken, they may bear in breadth to the lateral dimension of the strata which they intersect, it is plain that the whole mass of strata must have undergone a lateral extension equal to that quantity; a motion so great as not to be easily reconciled with the present regularity of the whole. It is also a singular circum- stance, that on the opposed shore of Sleat a different effect takes place, and proportioned, it wovdd here seem, to the number of the veins; the red sandstone strata of this coast being often turned from a slightly inclined into a vertical direction, with other considerable marks of disturbance. It is impossible to account for these apparently capricious differences, and we must for the present be content to rank them among the numerous unexplained appearances in which the science abounds. SKY. — GEOLOGY. TRAP VEINS. 399 Among the trap veins selected for particular remark on account of their interesting peculiarities, two are found traversing the white marble of Strath. They have been cut through in the operation of quarrying and are con- sequently accessible for a few feet in depth ; remaining in so fresh a state as to admit of a clear examination. They enter together into the present excavation, but immediately diverge ; in such a manner however, that their contact with the white marble can in many places be accurately followed. Toward the interior part of each, the substance is a black fine grained basalt, which as it approaches the side of the vein, becomes brown or greyish. At the same time its hardness diminishes materially, while its boundary towards the limestone becomes so irregular and uncertain, that it is often difficult to determine the line that separates the two. Various changes here occur, both in the composition of the trap and in that of the limestone. The former, as it becomes softer, is found gradually changed into a substance re- sembling serpentine, and is intersected by fissures con-, taining laminse of steatite. Still nearer to the limestone, lumps and more considerable veins of the same mineral occur, lying so confusedly in both that it is difficult to say with which they are most connected. If they graduate into the one they seem equally to pass into the other, while that part of the limestone in which they lie, changes its character, becoming magnesian, argillaceous, or silice- ous, and acquiring a great variety of colours. Those of the steatite are various, being pale blueish grey, yellow green, and dark olive green : it is besides various in quality, being sometimes much indurated and at others passing into transparent green serpentine. It is to this substance that the white marble is indebted for the colours that give rise to the numerous ornamental varieties it exhibits. Here therefore is an example of an intimate connexion between trap and steatite, a fact which is confirmed by a similar occurrence among the veins of Strathaird, the 400 SKY. GEOLOGY. TRAP VEINS. steatite being there disposed in the same manner where the veins intersect the calcareouH sandstone. This con- nexion is attended by a change in the substance of the trap by which it approaclies to serpentine ; the whole moreover appearing to be connected with the pre- sence of hmestone, since the change in question takes place only where those two rocks interfere. As this fact is important in the history of serpentine, a rock of which the natural affinities are but little understood, it , may be useful to add that an instance of the same nature, but much more decided, occurs in Perthshire, where a trap vein traverses a mass of limestone in a similar manner. In this case the transition from the trap to the serpentine is very perfect ; a line of the latter substance occupying the outer part of the vein while the limestone in contact with it is also fiUed with steatite. In describing the limestone of Broadford I formerly remarked that it contained beds of trap, often so equably interstratified as to be generally undistinguishable from regular alternations. An excellent example of their real nature, and of their identity with the analogous appearances in the north-eastern coast of Trotternish, is afforded by a circumstance occurring among similar beds at Borrereg. In one of these the bed, after a very extensive parallel course among the strata of limestone, undergoes a sudden flexure into an oblique position ; which shortly becoming vertical, it is then continued beyond reach of investigation under the usual form of a common trap vein ; intersecting at right angles in one place the strata to which it was parallel in another. The last trap vein which appears worthy of specific notice is found near Loch Oransa traversing the gneiss. It is remarkable for the mixture which it presents within itself of all the ordinary varieties of trap : being a tine basalt at the edge and passing by degrees into green- stone, porphyry, and amygdaloid. SKY. — PITCHSTONE. 401 I must yet add to this account, the description of a vein for which there is no other place in the arrange- ment. This consists of a reddish brown compact felspar with a splintery fracture, the fragments being translucent, and it is in some parts slightly porphyritic. The vein is vertical and of considerable thickness, occurring among the sandstone near the Kyle rich. Among the rocks, for which a place could not be found in the geological description without disturbing its order, pitchstone requires to be noticed. Although not found iti situ it offers, as a mineral specimen, some appearances which are interesting, and which I shall therefore describe.* The specimens in question were found on the hill of Glamich, and it is probable that they had been detached from veins which I was unable to trace. There are two varieties, one of which is black and very little differing from that of Rum, except that it contains a few dispersed crystals of glassy felspar; the other is olive green, and as it offers some apparently important peculiarities hitherto unobserved, it must be described more fully. This variety presents a granular, combined with a small conchoidal fracture, and is generally disposed in distinct concretions, which are either of the flat or curved lamellar form. It is remarkable for containing irregular rounded cavities similar to those of the amygdaloids, filled with compact grains of a greyish hue. The structure of these is so singular as to be deserving of notice. On breaking the smaller nodules they are discovered to consist of a greyish white enamel similar to that which is formed by the fusion of felspar. But in the larger, the centre is composed of glassy felspar, the crystalline transparency and platy fracture of which are perfect, while the surface to * Loose specimens of pitclistone are also scattered at the foot of Ben na Caillich, and I have just been informed by Professor Jameson that be has this year found the vein in a stream descending from that mountain, where we had both formerly sought fur it in vain. 1818, VOL. I. D D 402 SrKY. — MINERALS. a certain depth is converted into the white enamel. I have not observed this very pecuhar and striking appearance in any other pitchstone which has come under my notice, although there are appearances not much unlike it in some of the varieties found in Arran. In some parts the structure approaches very nearly to that of pearlstone. Those who conceive pitchstone, like basalt, to be of igneous origin, will have little difficulty in explaining this phenomenon, and will even find in it strong evidence in support of that opinion. It is unnecessary to enter on a reasoning so obvious. I have concluded, perhaps v/ithout sufficient evidence, that the pitchstone of Glamich, Uke that of Ben na Caillich, has been detached from veins. This deduction is made from the small quantity of fragments which are to be found, and from the circumstance that all the pitchstones of Scotland hitherto observed, actually occur in veins. On the side of Garsven I procured a fragment of the same mineral deserving of notice, since it offers an example of a rare occurrence, the transition of pitchstone to basalt. The fragment presents a mass of foliated basalt, the outermost part passing gradually into a fine black pitch- stone. From the analogous structure of the vein in Lamlash hereafter described, we are entitled to conclude that this was also the outermost part of the vein. I SHALL now proceed to describe the minerals which I observed in Sky, having reserved these details for separate consideration, lest they should interrupt the connexion of the geological remarks. The most nume- rous and interesting of these appertain to the zeolite family. They are to be seen in various parts of the island, but are found in the greatest beauty and variety in: the cliffs of the western shore, between Loch Bra- cadale and Loch Brittle. Talisker, which is the most accessible of these places, presents the richest assort- SKY, MINERALS. 403 ment to the collector of specimens. But in general the mineralogist can have no access to any specimens but those which fall from the cliffs and hav e long been exposed to the violence of the sea and the injuries of the air. However splendid therefore they may once have been, they are not always to be found in a state of good preservation. It is moreover often difficult to gain access to them on any terms, particularly along the other points of this wild shore ; since it is so beset with rocks on which a dangerous surf is almost always breaking, that it requires neither coimnon good weather, nor common dexterity in the management of a boat, to effect a landing and retreat without hazard. Analcime is the most common of all these minerals on the shore to which I have now alluded, and is found in the greatest profusion at Tahsker. It sometimes occupies cavities of considerable size, in different varieties of the trap, but seems to be far most abundant in the eartliy kinds formerly mentioned for which there is no name in our catalogue of terms. Occasionally it forms flat druses of considerable extent, occupying the sides of fissures, while in other cases, a single crystal is sometimes found in a cavity just sufficient to contain it. In the greater number of instances the remaining part of such cavities is filled with the filamentous nadelstein hereafter to be described ; and the crystals seem thus to be imbedded in a mass of cotton. The size of the ciystals varies from that of a pin's head to the diameter of half an inch; but in general they present only one modification, the twenty-four sided crystal wath trapezoidal faces, of greater or less regularity. The only other form which I found was the primitive, and of that I procured but two specimens, while the trapezoidal variety is abundant. The crystals described are sometimes opaque and white, at others they are mottled with a mixture of opaque and transparent parts, while in a third, but less common case, they are transparent. 404 SKY. — ]\IINERALS. In this latter state, when minute, they sometimes transmit the black colour of the subjacent basalt to which they adhere, so perfectly as to present a velvety surface of black crystals. In similar circumstances, transmit- ting the greyish or ochrey tint of the substance to which they are attached, they appear to possess a colour which a more narrow inspection shows to be fallacious. A few specimens occur of a flesh red, a colour frequent in almost all the minerals of this family, and very predominant in the different zeolites which are found at Glen Farg in Perthshire. I also observed a solitary specimen of a pale sea green hue, and I may add that a brick red variety, but uncrystallized, occurs in the amygdoidal rock near Loch Brittle. Chabasite is found in similar circumstances on the same shore, but is comparatively of very rare occurrence : it is common however in the rocks at the Storr, which for a considerable space consist of an amygdaloid containing this substance accompanied by stilbite. It is here so abundant, occupying cavities of greater or less magnitude, as to form a considerable part of the total bulk of the rock. As far as I have observed, this mineral is never, like the analcime, imbedded in the filamentous nadelstein, but it is not unfrequently associated in the same cavity both with stilbite and with analcime ; nor is it unusual to find minute and well formed crystals of this latter substance, imbedded in the crystal of chabasite. In some cases perfect crystals of chabasite are lightly sprinkled over the surfaces of crystals of stilbite, adhering so slightly as to fall off on the slightest concussion : in others, crystals of this mineral, as well as of the analcime, are confusedly mixed with the rhomboids of carbonate of lime hereafter to be described. The primitive crystal is by much the most com- mon, the modifications being rare and offering lew varieties; but it is very fiequently twinned, the angles SKY. — MINERALS. 405 of the one crystal appearing on the faces of the other : nor is it uncommon to meet with it in triplets, or even in more complicated groups, displaying an irre- gular mixture of prominent angles. The most common modification consists in the truncation of one angle ; sometimes two neighbouring angles are truncated, and occasionally this defect extends to three, the truncations being often so deep as to remove a third part of the rhomb. In other modifications a single angle and a single edsre are removed, or the truncations extend to two angles and two edges ; but I did not observe any spe- cimens in which these defects were extended to a greater number of edges. The edge is in some cases replaced by two or by three planes, or even by a greater number, so as to appear nearly rounded ; and each face of the rhomb is also frequently replaced by two planes meeting in an edge diagonally extended and sometimes rising by successive stages of planes parallel to the original face. These crystals are sometimes opaque, more frequently transparent, but in by far the greater number of instances they acquire a fallacious aspect of opacity in consequence of innumerable minute fractures by which they are per- vaded throughout. They are most commonly white, but the flesh coloured variety is also found, and their magni- tude varies from a twentieth to three tenths of an inch in breadth. Stilbite is the most abundant of the zeolitic substances in Sky, and is also the most generally diffused through- out the island ; it occurs along the shore which I have just described, but in less quantity than in the northern district. It is so common in the parishes of Kilmuir and Snizort that the roads are sometimes almost made of it. In other situations the decomposed trap falling into a powdery soil, leaves large accumulations of this mineral resisting the action of the weather long after the rock has moul- dered away, while it has in other instances been converted 406 SKY. MINERALS. / into a friable mass, so as to be mistaken for marie and used as manure. It presents scarcely any varieties of crystallization : the predominant, I might almost add the universal form, is that most common one consisting of very flat tetraedral prisms, terminating in tetraedral pyramids, of which the faces are placed on the edges of the prism. These are aggregated in distinct fasciculi, parallel or divergent, of which the groups sometimes affect the form of the consti- tuent crystals. In the neighbourhood of Loch Eynort nodules of great size occur, of a variety which is far from common, but which has I believe been found in the Faroe islands. These are either hollow or solid, and sometimes reach the enormous dimension of four and even five feet. The hollow specimens are crystallized Avithin, in the fasciculated forms already described. The peculiarity of this variety consists in its extreme frangibility : the least effort is sufficient to detach the plates of which it is formed, and it therefore falls to pieces in the very act of pro- curing it, unless great care is taken; the fracture is distinguished by an uncommon degree of the pearly lustre so characteristic of this mineral. So great is the frangibility, that the jarring of the hammer at one end of a large nodule is often sufficient to destroy the whole ; and it not unfrequently happens that when a large piece is obtained entire and has been laid down, although ap- pearing uninjured and resisting a strong effort of the hands to break it, yet in a few minutes it falls to pieces with a violence not unhke that which is known to happen in unannealed glass that has received tm injury. This variety is sometimes white, and much resembling sper- maceti in aspect, but in the greater number of instances it is of a delicate flesh colour. I may add to this enu- meration that I procured at Talisker a few specimens presenting the primitive form of this mineral. SKV. MINERALS. 407 The next of these minerals is nadelsteiu, which is found in three states, a compact, a mealy, and a crystallized form. Of these, the compact kinds sometimes recede so fer in character from the mineral in its most acknowledged forms, that the names of those which occupy the dis- tant points of this range can only be determined by tracing the gradation of the several varieties. The opaque whiteness, the toughness, and the radiated dispo- sition of those which may be considered as forming the first remove, serve to connect them with the best charac- terized specimens. By a series of gradations the radiated structure disappears, while the mineral acquires additional toughness, verging in aspect first to chalcedony, and lastly towards chert ; wdiile in some cases it would be difficult to distinguish it, without trial of its hardness, fi"om the white limestone of Ireland. In this state it is not scratched by hard steel, while its toughness is such that a hea\-y hammer makes no more impression on it than it would on a similar mass of iron. Where the tran- sition into chert is most complete it is scarcely to be distin- guished fi'om those cherts which in other situations occur in trap, and are so frequently to be seen in those traps where nodules of calcareous spar and of chalcedony are found together. Lastly it passes into pure quartz, although there is often a slight boundary discernible between this mineral and the chert that preceded it. The causes of this gradual change may be attributed to the successive diminiition of the proportions which the other constituent earths of this mineral bear to the silica which it contains. I need not point out the difficulty of reconciling such a supposition to the general theory of mi- neral species and of definite proportions, since mineralogists are a;lready aware of it, and since many similar cases, attended by the same difficulties, are well known. It is a question too important to be discussed without much more numerous and better established facts tlian those which we yet possess, and it will hereafter become an object of 408 SKY. — ^MINERALS. serious investigation to mineralogists, when their science shall have made further progress. The mealy variety occurs under different aspects, by which its nature is in some measure illustrated. This condition has, I believe, been generally attributed to the loss of its water of crystallization, the result of decompo- sition. It is obvious however that this is not the cause, since the specimens of this variety are found in the centre of solid nodules of the glassy or compact kinds, where neither air nor water can have access, and where they are accompanied by crystals of absolute transparency : they are also found intermixed with and investing solid nodules of the toughest varieties, deeply imbedded in large masses of rock where the elements are effectually excluded from them. There are three principal forms of this variety. In the first it is disposed in a radiated or rather in a ramose manner, in fine fibres possessing the peculiar lustre and softness of the finest white pulverulent talc. In a second case it forms distinct globular concretions of extreme minuteness, not to be discovered without the aid of the lens ; and in a third instance, which I observed near Loch Eynort, a mass of globules of solid radiated nadelstein, very much resembling some of the oolites, is intermixed throughout with farinaceous scales of the same substance having the greasy aspect and lustre already described. In speaking of this lattpr variety I have ranked it with nadelstein : it appears to have been formerly placed with the mesotypes, partly because it is found associated with them, and partly because of the theoretical views which have been held respecting its origin.' it will be for mineralogists of more authority to consider whether it does not deserve a separate place as a species: the question is not of a nature to be determined by geometri- cal analysis, as far at least as the varieties already found extend ; and the delicacy and uncertainty of unassisted chemical analysis in questions of this nature, are far too SKY. — MINERALS. 40^ great to tempt us to seek a new place for it by this species of investigation. The last variety exhibits a distinct crystaUization ; but crystals of tangible magnitude are so rare that I only procured one specimen in which the forms could be deter- mined. It is unnecessary to describe these as they are well known to mineralogists. To compensate for the deficiency of large crystals of this substance, a profusion of that variety is to be found, which bears a general resemblance to amianthus : it is popularly known in the country by the name of cotton stone. These filaments occupy the cavities of the trap, and are sometimes accompanied by analcime, as was already remarked. They vary much in minuteness and delicacy, as well as in their state of aggregation, and hence many variations in their external aspect may be observed. At times they are placed in distinct straight needles, in other cases they are crowded into a dense mass, while in a third they are so entangled as to resemble a lock of cotton w^ool. Frequently they have the lustre of common silk, with its apparent dimensions, while they are in some instances so far attenuated as to resemble tlie silk of certain spiders. When the trap has fallen into powder, they are occasionally detached in light com- pacted balls, which are blown away by the winds and float on the surface of the water : in all these cases the microscope discovers their glassy transparency, but its powers are insufficient to determine their form, from the dazzling play of reflected and refracted light which they exhibit. In some rare instances this variety seems as if it passed into the mealy ; in reality it becomes opaque and puts on a mealy aspect to the naked eye ; but this is readily distinguished by the lens from the specimens which I have described above. The last specimens in point of structure which require notice, are radiated and intermixed with crystals of hornblende, producing a com- pound of an unusual appearance. 410 SKY. — MINERALS. The specimens thus described are almost invariably colourless and transparent, or white ; but occasionally they assume a brown tinge. One specimen occurred of a sea green hue and of perfect transparency ; but the flesh colour not uncommon in this mineral was not observed, although found in the other members of this family which are here seen. With respect to the exact locality of this substance, I have only found it at Talisker and at Dunvegan, although it is probable that it exists in many other parts of this extensive island, which the labour of years v*'ould scarcely suffice to examine with the scrupulosity necessary for this purpose. In the spot already quoted between Loch Eynort and Loch Brittle, I also found laumonite, one of the least common of the zeolite family. It is occasionally mixed with stilbite, and appears also to exist in the amygdaloids, in which cases it seems to determine or accelerate their decomposition. But it is also found in large masses on the shore, mixed with irregular crystals of calcareous spar, and containing cavities in which it is crystallized at liberty in distinct and perfect forms. These masses attain to twenty pounds in weight, and though now, while at rest, in a state of apparent integrity, they crumble to pieces on the slightest effort to move them. The weather appears to exert no other action on them, since the mineral possesses its snowy wliiteness and bril- liancy equally on the exposed surfaces as in the interior. Their present state offers a singular contrast to their former one ; since they must have been in a far different condition to bear the fall from the high cliffs whence they have been detached, without entire destruction. In the same fertile spot to the mineralogist I also found the no less rare substance ichthyophthalmite. It is not abundant, but to compensate this, the crystals are perfect and of great size, presenting two modifications. In the first the square prism is truncated on all the angles, and SKY. MINERALS. 411 being attached by one of its flat sides to the hard mealy- zeolite with which it is connected, is exhibited in great perfection, the crystals reaching from half an inch to nearly an inch in length. In this case the extremities -pos- sess the pearly Itistre that generally attends this mineral. In the other modification the truncation of the angles is such as to produce a pyramid on each extremity of the prism, and in this case they are as transparent as glass, becoming gradually opaque towards the middle and pris- matic part of the crystal. Like the other zeolites it occu- pies cavities in the amygdaloidal or basaltic rock. I may add that I found one solitary crystal of the same sub- stance at Dunvegan. Olivin, a mineral by no means common in the traps of Scotland, occurs in the same place. It is even here but in s^mall quantity, since it is found but in one block of the many hundreds which strew this shore and have fallen from the cliffs above. The rock that contains it is, like the generality of the amygdaloids in the same place, a black indurated clay. It forms an uniform kind of mixture with this substance, being in the form of irre- gular grains, but so abundant that when, after exposure to weather, the clay has decayed, the whole seems one mass of olivin. Prehnite, a mineral so nearly allied to the zeolites, i& also found in Sky, but it is far from common, while the specimens are at the same time of trifling magnitude- It occurs in the trap of Portree, «nd at other points along the eastern «hore ; as well as at Strathaird, in the trap veins which traverse the sandstone, as I have already mentioned. On the shores opposite to the point of Clachan in Rasay it is found in a rock, which, although not very common, occurs in different parts of the Western islands. This rock is a compound of augite, glassy felspar, and comm.on felspar, the two latter having fre- qviently a greenish hue. Besides the decided nodules of 412 SKY.— -MINERALS. prehnite, the same mineral is intermixed throughout so as to form an integral part of the rock, often passing into mesotype, as it appears to do in other more decided instances. It has been said by Haiiy that prehnite has not been found forming an integrant part of rocks ; but as a compound of a similar nature occurs in the Kilpatrick hills near Glasgow, an exception must be made in favour of these instances. I may here add, that a corresponding rock may be seen on the opposite coast of Rasay. It is perhaps superfluous to say that nodules of chalcedony, often hollow and containing crystallized quartz, are occasionally found in the trap rocks of Sky, since they are of such common occurrence in this substance. They must nevertheless be considered rare here, and it is more rare to find them s >lid lilce those so common in Scotland. The only specimens I found were near Loch Brittle, and these were of a dull grey colour, zoned, but presenting little v. licty. The quartz sometimes forms nodules without the investing crust of chalcedony, and the cavities are sometimes, in addition, sprinkled wi::i crystals of stilbite, of analcime, and of chabasite. Of those mineral substances which are the least frequent in trap rocks, steatite occurs in considerable quantity; it is tender, foimd it to be 21° near the Craig of Ailsa. My own trials were independent of the ship's attraction, as they were made on shore ; the needle being elevated as high as possible above the surface. CANXA. DESTRUCTION' OF HOCKS. 45 1 this process ; so interesting in a chemical view, and so important in its results, from the extensive changes which the surface of the earth undergoes, both from its accumu- lated effects and from their remoter consequences. The appearance in question is most conspicuous in the breccia that occupies the lowest situation on some parts of the shore ; but is not limited to that rock, since it also occurs in the prismatic trap and in the amygdaloid.* The waste of these rocks from the action of the atmosphere is considerable, and the indications of it are visible in many other cases besides those of the detached masses so remarkable on the shore of Sandy Isle and on the eastern side of Canna. But vv'here the high water mark commences, the indications of which on rocky shores are almost always sufficiently marked by the Lepas Bala- ims, there is a sudden stop to the wasting process, which, although it may vary in the different kinds of trap, is generally visible every where. In consequence of this, a kind of platform is seen at low water, skirting the bases of the cliffs ; often reaching to a great extent, and thus indicating the different degrees of rapidity with which those parts of the rock exposed to the air only, and those subjected to the vicissitudes of sea and air together, have undergone decomposition. In some instances, where detached turriform or pinnacled rocks are seen, the ap- pearance is peculiarly remarkable, since they seem as if they had been erected on solid platforms, the flat sur- faces of which denote the level of the sea at high water. Contemplating the rapid waste of these rocks, it is easy to look forward to a time when the pinnacle shall disap- pear, and no trace of it remain but the half sunk rock, breaking at high water and denoting its former place. There can be no question respecting the nature and existence of this appearance, since it occurs in other places besides Canna; but as yet I have had no oppor- * Plate XIX. Ik. 1. 462 CANNA. — DESTRUCTION OF ROCKS. tunity of extending the observations so far as to decide to what kinds of rock it belongs or to which it may possibly be limited, I may however enumerate those places where it is to be seen. It is very conspicuous in the island of Staffa, where the excess of waste in the parts exposed to the atmosphere only, above that where the action of sea and air alter- nate, is strongly marked by the columnar causeway which in many places extends so far beyond the vertical face of the island. I have pointed out a similar appearance in Rum, in the platform which extends from Harris to the point of Bri- dianoch; and it is also to be seen, although in a less marked manner, on the southern shores of Egg, as well as in many parts of Mull and Sky which it is unnecessary to enumerate. In all the cases here quoted, the rocks are of trap or syenite, but the circumstance is by no means limited to these. A long range of secondary rocks has been described as extending from Portree to the northern end of Sky, and the same has been shown to exist on the eastern side of Rasay. In both these instances, the strata being nearly horizontal, and the cliffs decomposing so as to present mural faces, the effect is equally remarkable as in Canna or Rum where a similar mode of wasting prevails. The strata, whether of sandstone, shale, or limestone, are here found projecting far beyond the cliffs in the form of flat shores, never rising above the high water mark; while the surface of the uppermost stratum, whatever that may chance to be, appears to resist all efforts towards waste ; at least for a comparatively long time. A similar dura- bility under the same circumstances is found in the gry- phite limestone of Sky and of the adjacent islands; although the effect is less conspicuous in consequence of the inferior altitude of the land. The result in these cases is seen in the long extended reefs and foul shores which render this coast so dangerous to vessels engaging CANNA. — DESTRUCTION OF ROCKS. 463 too near with the land. I may add that the same circum- stance takes place in the island of Muck and in the Isle of Man. In these latter examples limestone is the pre- vailing substance ; but it is worthy of notice that even the very soft shale found in Pabba and on the Broadford shore, seems to lose its decomposing property as soon as it has wasted to that level where it becomes exposed to the diurnal action of the sea water. It may be perceived by the instances thus adduced, that the most conspicuous examples are found in the trap rocks and in the secondary strata, but the effect does not appear limited to these alone. To the same cause are doubtless owing the projecting rocks which are almost invariably found to skirt rocky shores of whatever sub- stance these may be composed ; the further ruin of the cliffs appearing to meet with a check wherever the sea comes into contact with them. The difference in the apparent effects in the case of these rocks, seems partly to arise from the different mode in which they are disposed, in consequence of which the waste cannot take place in angles so nearly vertical, nor the effect arising from contrast be so strongly perceived ; and partly, it is to be presumed, from their greater durability and more tedious destruction. It is perhaps not difficult to assign the causes of this phenomenon. The ordinary causes of decomposition are too well known to require enumeration : and one of these appears equally to act in both cases ; namely, the change produced in the iron of the compounds by the access of air and water. But from the other and next most obvious cause of decomposition, namely, the action of frost, it is evident that the rocks are in one situation excluded, while they are exposed to it in the other. To this we are per- haps to assign the whole difference above mentioned ; and we are thus led in these colder regions, to ascribe a much greater power in changing the face of the earth to this agent, than to any chemical actions ; the operations of 464 CANNA. DESTllUCTION OF ROCKS. these appearing to be confined within hmits comparatively narrow. It is evident that similar observations, made in countries where frost is unknown, would be required to confirm this view; but the subject not having heretofijre engaged the attention of any one, I am unable to adduce any remarks bearing on the question. If the fact be really such, there will result a great difference in the dura- bility of mountains as well as of sea shores in different parts of the earth ; but it is unnecessary to enter deeper into this speculation. At the same time I cannot conclude the subject without remarking that this protecting power of the sea is a fact of considerable importance in marine architecture, and may lead to valuable precautions in cases where the architect has a choice on what foundation his light house or his pier shall be erected. It may perhaps induce him, in cases where he has such a choice, to prefer a submarine basis ; particularly when the rock intended for the build- ing has from its nature a tendency to exfoliate or decom- pose. Had the foundations of the castle and of the walls of Conway been washed by the sea, so many parts of these structures would not now be suspended in the air and relying on the tenacity of the work. It is satisfactory also to know that the rotten state of the gneiss on which the Eddystone lighthouse is built, presents no cause for fear respecting the permanence of its foundation. SANDY ISLE. GENERAL DESCRIPTION. 465 SANDY ISLE.* The preceding remarks on Canna, are for the most part so applicable to this island that little need he said respecting its structure. It may almost indeed be viewed as constituting a portion of the former, the two being united at Ioav water by the beach of shell sand already mentioned, and by their union forming the most frequented harbour on this coast. The bustle and life which it presents, when crowded with merchant vessels detained by adverse v\inds or foul weather, form a striking contrast to the solitude of those scenes where the geo- logist is often compelled to cast his anchor ; either in pursuit of his peculiar objects, or as a refuge from the elements which the want of sea room will not allow him to brave. Perhaps he may not think it the least of the merits of this port that he can here renew his sea stores ; not easily replaced in a voyage which is calculated to impress on his mind the numerous, though often unac- knowledged conveniences, for which he is indebted to the habits of improved life ; and of which he has perhaps never before been thoroughly sensible. That side of the island which lies next to Canna is low, while towards Rum the land rises into gentle eleva- tions terminating in abrupt cliffs and skirted with detached masses of rock of considerable height. The rocks called Dun na Feulan (the gull rocks) afford almost the only picturesque scenery which these connected islands possess. There are two of different magnitudes but of the same height, situated at a short distance from the cliffs. Their altitude does not appear to exceed 100 feet, but they form some striking combinations with the surrounding cliffs. The smallest is thin in proportion to * See the jjeneral M:t[>. VOL. 1. H 11 466 SANDY ISLE. — GEOLOGY. its height and of a steeple-like form, while the other resembles a huge tower. They are seen to great advan- tage in gales of wind, when the high momitains of Rum are involved in clouds and the tide of this rapid strait is breaking on the shores ; circumstances indeed always peculiarly appropriate to the wild features of these rocky coasts.* The general alternations of the trap with the conglo- merate are more visible in Sandy isle than in Canna ; and it is much more easy to trace the beds of coal and shale. But there is one peculiar circumstance here in the dispo- sition of the conglomerate, which is worthy of remark : it occurs in the steeple-formed rock above mentioned. That substance is here divided from the solid trap by a vertical, instead of a horizontal line ; the one side of the mass being constituted of the former, and the other of the latter. In other respects the substances and their connexions are precisely the same as in Canna, or in the other parts of this island where they lie in a horizontal position.^ It is not easy to explain this appearance ; but it is not impossible that the whole mass has been thrown down from a superior position, into that in which it now stands ; as there are no symptoms of a similar general disturbance in the island itself, and it is not conceivable that the conglomerate should have been deposited in its present position in one hmited spot only. Sandy isle, like Canna, presents examples of a circum- stance rare in the Western islands ; namely, loose frag- ments of a different rock from that of which it is formed, lying on the surface. These are large blocks of red sandstone, somewhat rounded ; and they are found in considerable abundance on the flat shores of both. They are not to be seen in the higher parts of these islands ; nor are there any strata or remains of strata now existing, * riatc XIX. i\g. 2. t I'l^'^*' X^X. fig. 3. SANDY ISLE. DISEASES OF THE HIGHLANDS. 467 from which they could have derived their origin; while they are far too large to have been accidentally trans- ported as ballast, or brought intentionally for building. The rock of which they consist is that which forms so large a portion of Rum, and of Sky. They may possibly have been transported from the former of these islands before those changes of the surface had taken place of which there are not wanting abundant indications over the whole globe. It is however more probable that they have been derived from portions of the conglomerate rocks formerly described, at a period when these occupied a greater space than they do at present ; the most durable substances remaining thus insulated, while the cementing trap has mouldered into soil. While detained by gales of wind in the harbour of Canna I had an opportunity of observing the characteristic veneration which the Highlanders possess for medicine ; proportioned, as it would seem, to the scarcity of its pro- fessors. It would be unpardonable not to bestow a cursory notice on the diseases of the Highlands ; since they form a frequent object of inquiry among those who have com- paratively few opportunities of being informed respecting them. Fever rarely now visits this country, although, by all concurrent testimony, once prevalent and fatal. The change cannot be attributed to superior cleanliness or comfort ; as in these respects the houses have undergone no change, and the inhabitants but little : it doubtless originates in the more ample svipply of food ; the con- tagion appearing, in all the recorded instances, to have been generated after seasons of scarcity ; a cause of fever well known to physicians. But I must remark that it has within a few years found its way with renewed severity into some of the most improved districts on the borders of the Lowlands ; the consequence, it is to be feared, 46s SANDY ISLE. DISEASES OT THE HIGHLANDS. of partial and improvident ameliorations in the accommo- dation of the lower classes. Under the ordinary construc- tion of the cottages there is no chimney, as the fire occupies the centre of the building ; so that the smoke and heated air must fill every cranny before they can escape ; while a perpetual ventilation being kept up from doors and windows which cannot be closed, it is difficult for contagion to be accumulated. The partiality of the Highlanders to this rude mode of warming their houses, proceeds from its economical and effectual nature ; its utility in preventing the generation of disease being too refined for their observation, although there can be little doubt of its efficacy in this respect. In the improving parts of the country, the proprietors, very laudably stu- dious of the comfort of their tenants, have introduced fire- places with chimneys ; either by building themselves, or by limiting their tenants in their leases to that construc- tion. Thus the effectual circulation of heat and air is counteracted, and the penetralia of a Highland hut, doomed never to meet the light of day, are suffered to accumulate the effluvia of generations. The chimney is premature ; and till general habits of cleanliness are introduced, the result here pointed out must occasionally follow; while the contagion once generated becomes permanent; being recalled into action during successive favourable seasons. Bleeding is the universal remedy in this disorder, and I may add that the practice is successful. On no occasion have I witnessed any remarkable popular remedies or superstitious practices. These, with other peculiarities, are fast wearing away. Among the most fatal diseases in this country, are acute pulmonary inflammations. Bleeding is here also performed by the natives, but in so insufficient a manner as not to check the progress of violent cases, of which the fatal terminations are but too frequent, however occasionally protracted. Consumption is by no means prevalent, SANDY ISLE. DISEASES OF THE HIGHLANDS. 469 although instances of it occur in cases where the scro- fulous habits, not very uncommon in this country, have been called into action. The diseases consequent on scrofula take place here in the dark temperament equally as in the sanguine ; doubtless in consequence of the insuf- ficient food of the labouring community ; a circumstance always ready to excite its dormant energies where they might not otherwise appear. It might be expected that chronic rheumatism would be common in a climate so moist, and among a people to whom rain seems a matter of indifference ; since they will not often seek shelter from it, even when in their power. This however is not the case, nor have I observed that rheumatism in its other modifications is more prevalent than in the low country. Intermittents are not known ; nor are the autumnal diseases in general to be found where the season itself cannot be said to exist. I know not that there is any thing worthy of notice respecting the eruptive epidemics. Disorders of this class are not readily propagated far among a scattered population : but for the honour of the country I must remark, that vaccination is almost every where anxiously sought after, notwithstanding the imputed fatalism of the Scottish presbyterians. The sibbens is unfortunately too well known as an endemic in the Highlands, but like other contagions which require intimate contact for their propagation, it is still limited to particular districts. Among the islands it scarcely occurs, except in Isla, where least of all it would be expected ; since the inhabitants of that island have advanced considerably beyond their neighbours in improvement. With respect to cutaneous affections it may safely be said that the supposed opprobrium of the country has vanished. The extreme prevalence of dyspepsia is perhaps the most characteiistic circumstance in the whole catalogue 470 SANDY ISLE. DISEASES OF THE HIGHLANDS. of HiMiland ailments. This is so common, that among the female sex it is rare to meet one of a certain age free from it ; among the men it is not so prevalent. It is attended witli all its. usual train of Protean symptoms ; and often, to a degree of violence which will surprise even the physician long versant in the formidable catalogue with which, in the course of more fashionable practice, he is hourly persecuted. The mental affections which so commonly accompany it are also here exhibited in per- fection ; in all their modifications of hypochondriasm, and with the caprices and hallucinations which have been falsely supposed to arise from indulgence and indolence. He who is accustomed to administer to the diseased minds of the rich and the luxurious, believes that he would often find a remedy in abstinence, in occupation, and in exer- cise ; provided he could prevail on his refractory patients to abandon their usual gratifications, the supposed causes of this disease. Here, he will find all these supposed remedies in compulsory use, and the disorder equally obstinate and equally defying his powers of cure. Philo- sophers are often accused of generalizing prematurely; and certainly in assigning the causes of this malady phy- sicians have not been deficient in that respect. If labour, occupation, and a moderate diet, could remove or prevent this disease, it would not be found here ; if real care could prevent the attack of that more formidable invader of human happiness, imaginary care, the diseases of the imagination would not exist in the Highlands. Whether the cause may not consist in the reverse, the want of sufficient food, is a question which will probably be answered in the affirmative. How far this prevalence of the hypochondriacal affection may conduce to certain mental phenomena for which the Highlanders have been remarked, is a question of some interest. It is in such minds at least that the hallucinations of second sight and other supernatural appearances might be expected to pre- dominate. SANDY ISLE. DISEASES OF THE HIGHLANDS. 471 I have hinted at the deficiency of food among the Highlanders. The introduction of the potatoe has done so much to remove this once prevalent cause of misery and depopulation, that such a want is scarcely suspected. It is however still apparent. At present, it is true, the Highlander rears a fair proportion of children, the average number varying between three and four ; a great proof of amelioration in the means of living. The children are also universally strong, ruddy, and handsome, yielding nothing in that respect to their better clothed and better lodged neighbours of the low country, or of England. This air of health and good feeding continues till the age of labour, and for some space beyond it. But at twenty, or shortly after, an evident change takes place. The skin shrivels, the bones of the face project, and the marks of age, already perceptible, increase rapidly to that period in which it becomes sensible in the labouring part of the community every where. After that, there is perhaps no further comparative difference, and the limit of the Highland labourer's life stands on a fair averao-e with that of the Lowlander or Englishman. This change is most sensible in the women. Instances of beauty are by no means uncommon in female children. But it vanishes at seventeen, and shortly after, the marks of age hasten on so rapidly that, (with deference to the Highland fair it must be said,) they acquire that aspect so dreaded by Queen Elizabeth, or the ancient fair one recorded in the well known epigram of Plato. This effect seems to proceed from the insufficiency of the food com- pared to the labour ; and to those who have seen the country I need scarcely say, that an equal, if not a greater share of that labour, is often the lot of the females. There is reason to suspect, from the greater durability of the lower classes of the Irish, where potatoes form the sole food, that this root is superior in its nutritive qualities to oats or barley; and w^e may therefore slight the misplaced compassion of those who lament the hard fate of the 472 SANDY ISLE. DISEASES OF THE HIGHLANDS. Highlander in the islands where a sufficient supply of oatmeal cannot be procured, and where the inhabitants depend on the potatoe. If the rapid increase of popu- lation, abundantly obvious throughout the country, had not in itself a necessary tendency to increase the produc- tion of this root and diminish that of grain, it is likely that the experience of the people themselves will gra- dually, however slowly, produce the same effect.* It has been often said that examples of longevity were common in the Highlands, and the tale has been repeated till it has almost become an axiom dangerous to doubt. A well known and remarkable instance is often quoted from Pennant, but it is probably a solitary one ; since other inquirers have not found similar cases, and no satisfactory evidence has been produced to justify the general assertion. The tourist who hurries through the country may perhaps adopt this notion, from the numbers of old people whom he sees in the cottages, or engaged in some sort of labour when nearly past the power of labouring. But it must be recollected that the aged and infirm continue to reside with their children when no longer able to maintain themselves ; and that there is no asylum, like the workhouse or hospital of England, where these objects are concealed from the public view, and almost lost to the public recollection. Hence the aged are seen every where ; and hence the easy but superficial conclusion, that they are in greater proportion here than in England. * It must be remembered however that there is a countervailing evil in the use of the potatoe, which, however distant, is of a most important nature. It is indeed obvious that the potatoe system, as it is called, is making a rapid progress in many districts ;■ and it is to be feared that in no long time the consequences that have followed it in Ireland will ^1^0 find their way into tliis country. \l.)H RUM. GENERAL DESCRIPTION. 473 RUM.* Although the rough and dangerous shores, the track- less surface, and the perennial rain of this island, are repulsive to the general traveller, the geologist will here meet with appearances of such interest, as to induce him to brave its tempests and to defy the toil which he must encounter in its investigation. So rude and barren is Rum as to be of less value in proportion to its extent than almost any one of the islands described in this work. Even kelp, that staple commodity of the Western islands in general, is nearly denied to this, its steep and weather- beaten shores refusing a hold to the marine vegetables which abound throughout this sea. The general aspect of Rum is mountainous, and it may be said to consist of an irregular group of high hills rising out of the sea ; without plains, and scarcely diversified by an intervening valley. This group may, in a general point of view, be considered as divided into two parts, the highest occupying the eastern extremity of the island, and that next in altitude the western. But the division is not strongly marked, since it consists only of a lower class of mountains ; and I may add that the northern side of the island presents a still lower range descending towards the shore with a more gentle declivity. I had an opportunity of observing by the barometer the height of Oreval, the most elevated of the western summits, and found it to be 1798 feet. Storms and clouds prevented me from repeating the observation on Ben More, the highest of the eastern group ; but it may be estimated at 500 feet more, while the two remarkable sharp pointed * Rum, Danish, wide, ample, roomy. A more probable etymology than Dean Monroe's Ronin. — See the Map. 474 RUM. GENERAL DESCRIPTIOX. sumniits of Haiival and Haiskeval seem, fi-om various points of view, to possess nearly the same elevations.* The eastern group, including Hahval, Haiskeval, and Ben More, is almost perpetually involved in mist. If the clouds descend on the CuchuUin hdls of Sky, it rarely happens that those of Rum, although so much inferior in height, are free. To this is owing the sfreat proportion of rain which falls in the island, and hence also arises in a ojeat measure the moory and unprofitable state of so large a portion of its surface. This property of arrest- ins the clouds on their arrival from the western ocean, depends partly on the absolute height of the mountains, but still more on their insulated position : as they fonn the onlv hisch land that Ues between Sky and the moun- tains of MuU ; both equally noted for the torrents of rain which they precipitate on the surrounding country. It is here that I have frequently observed a meteorological phenomenon, which is also common in St. Kiida; namely, that appearance in the clouds which is termed parasitical. The general causes of this phenomenon have been often discussed by philosophers : but having on one occasion observed it to be attended with particular circumstances, it will not be superfluous to describe the appearances then witnessed. Those who have travelled in mountainous countries must have often remarked tiiat, even in a strong wind, a cap of mist will frequently involve the summit of a single hiD : appearing to be in a state of absolute rest, while the neishbouring clouds are sweeping rapidly along under the influence of the sale. This appearance has sometimes been attributed, either to the existence of par- tial currents of air, or to some pecuhar electrical condition * As diere is no other map of the island than the sea chart, I hare been obliged to give such a sketch of the ground as couid be made hy the eye, widioat which the fdaces and rdattoos <^ the rocks that form it woald be unintelligible. RUil. PARASITIC CLOUDS. 475 of the hill, which ^ve it the power of retaining a covering of Tapour within the sphere of its influence. On the occasion to which I allude the true nature of this very common phenomenon was apparent ; while a beantifiil example of the formation of clouds in a transparent atmosphere was at the same time presented; attended with other circumstances less easy of explanation. The wind was north-east, and the breeze, which h?d blown moderately all the day, began to freshen con- giderably as the sun went down. Not a cloud was to be Been in the whole hemisphere while the snn was abore the horizon. The island of Rmn was about three milpfg to the westward, and its two most remarkable summits Hahval and Haiskeval were visible, the vessel being in such a position beating to windward as to preserve a parallel with the current of wind and the land. Shortly, a cloud appeared hovering over one of the mountains, and maintainins a constant distance at an elevation of 200 or 300 feet above it ; never approaching or receding from it materiallv, while a similar cloud involved the other, restin«"'»:'vl''i'