m ^r's^ Nt?<:^ Ahi Digitized by tine Internet Arciiive in 2010 witii funding from The Library of Congress littp://www.arcliive.org/details/modernliiglifarminOOwyat MODERN HI JL A TREATISE ON Soils, Plants, and Manures, Francis Wyatt, M PROFESSOR OF AGRICULTURAL CHEMISTRY, CHEMICAL ANALYST, ETC. AUTHOR OF "THE CHEMISTRY OF SULPHURIC ACID MANUFACTURE, "the PHOSPHATES OF THE WORLD,'' ETC., ETC. NEW YORK: C. E. BARTHOLOMEW, PUBLISHER, 23 College Place. 1886. ^^^ Entered according to Act of Congress, in the year 1886, by C. E. BARTHOLOMEW, in the office of the Librarian of Congress, Washington, D. C. \r,n \\^ F'RKKA CE. TO THE AGRICULTURIST OF AMERICA. My Dear Sir . The pages which. I now pass into your hands are the result of much study and hard work, combined with a long special experience in matters pertaining to your vocation. They have been written solely for your information and advantage, and I trust their sincerity and utility will be found to fully justify my familiarity in thus personally addressing you. For many years past I have had constant intercourse with men of your profession, and with the best practical experts in chemical manures in every part of Europe, and I judge that the time has come to impart to you not only the results of my experience with them, but also of my own personal investigations. You will, perhaps, tell me that too much has already been written and said upon the purely chemical side of this great question ; that you have bought and read books and periodicals without number, and that you are not very much further advanced to-day than you might have been had you kept your money and read no books at all. I fancy I can hear you saying, that men of my profession have not yet found out the secret of imparting knowledge to men of yours ; that where you have too little theory, tJiey have too little practice, and that their unfortunate habit of wrapping round their teachings a dark mantle of scientific words which you do not understand, has hitherto occasioned you more confusion than benefit. That because of this there is a lack of good special literature, I am far from pretending ; indeed, I doubt not that I could derive benefit from much of it, were I to read and digest it. But I nevertheless maintain that the books on agriculture, while not above your intellect or intelligence, are, as a rule, written in a style beyond the plane of j^our scientific education. Were I to offer you the best book written in the Latin tongue, treating upon a subject familiar to you, the chances are ten to one that j'ou would not comprehend a word, and the book would be tossed into a corner. Should one of your children — having been taught to read and translate the Latin language — stumble upon this book, and read it to you in your own mother tongue, you would be struck with wonder at the value of its truths and the simplicity of its lessons. I fancy this is exactly the case between you and our contempo- rary scientists, who, persisting in addressing you in unfamiliar language, are answerable for 3'our now putting a number of good books, that are written for you, " on the shelf." My earnest endeavor has been to bear ull these things in mind ; thus, while seeking not to deviate one inch from the broad line laid down by true agricultural chemistry, I have sought to treat each subject in the plainest language possible. If I succeed in doing no more than lay the foundation upon which you can pile up future knowledge ; if I merely convince you of tlie necessity for thought, study and experiment, I shall consider that I have aided you in making the first great stride in the right di- rection, and shall find in that fact alone a sufficient reward for the service I have performed. I am, my dear sir. Very truly yours, FRANCIS WYATT. New Yokk Mercantile Exch^\.]sge Building, Cor. HrDSON & Harrison Sts. , New York City. IN DKX. CHAPTER I. PAGE General Introductory Remarks — Influence of Climate — Origin of Scientific Agriculture — Its Progress in America 5 CHAPTER II. Theory of Scientific Agriculture — Formation of the Globe — Its Temperature — Composition of the Earth — Its Principal Rocks — Chemistry of Vegetation — Necessity for Geological Knowledge — Remarks on Drain- age and Irrigation 9 CHAPTER III. Minerals Necessary and Injurious to Plant Life — How Plants Absorb Their Food — The Gases and Their Various Transformations — Nitrogen — Phenomenon of Nitrification in the Soil — Sources of Nitrogen — Its Manufacture — Its Fixation — Its Assimilation — The Necessity for Its Application as Manure 13 CHAPTER IV. Phosphates — Discovery of their Active Principle — Use of Bone Manure — Discovery of Mineral Phosphates — How They Occur in Nature — Their Form in the Soil — How They are Made Soluble — How They are As- similated by Plants — Migrations of Phosphorus — The Necessity for Artificially Introducing Phosphoric Acid as Manure 18 CHAPTER V. Potash : Its Action on the Soil — Is it Essential to Plant Life ? — Results of Direct Experiments — Its Necessity Made Clear — Sources of Its Supply — Lime — The Liming of Soils — Its Chemical Action — Its Absorbing Powers — Its Action on Sulphurous Ores — Its Action on Iron — Alu- mina and Phosphoric Acid in the Soil — Necessity for Its Abundant Use 23 CHAPTER VI. How Soils Lose Their Nitrogen — Table of Proportions — Necessity of Soil Analysis — Table of Physical Elements and Chemical Constituents 28 CHAPTER Vn. Physically Perfect Soils — Strong and Light Soils — How to Amend Clayey Land — Clay Burning — Treatment of Sandy Soils — Green Crops as Manure — Remarks on Disintegration — " Fairy Rings :" Their Exist- ence Explained — How to Keep Pace with the Times 33 CHAPTER VIII. Progress of the Manure Trade in the United States — Low Price versus Real Value — How the Farmer is Swindled — Bogus Manures — Necessity for Analysis Demonstrated — How to Stamp Out the Evil — Advice to Manufacturers 38 CHAPTER IX. The Different Kinds of Manure — Notes on Vegetable Manures — Animal Products — Their Annual Reckless Waste — Estimate of the Loss to Agriculture — Hints on Their Preservation and Utilization — Guanos Described and Analyzed — Their Variable Quality — Fish Manures — Table of Nitrogenous Substances 44 CHAPTER X. Farm-Yard Manures — Composition of Their Liquid and Solid Elements — Comparative Value of Absorbents, with Analyses — Composition of Various Straws — Superior Value of the Liquid Substance — How to Preserve and Utilize it — Treatment of Manure Heaps — How to Com- plete Their Value as Fertilizers — Their Decomposition — Formation and Description of Humus — Experiments on Freshly-Made and Fer- mented Manures — Results of Each Experiment — General Remarks 50 CHAPTER XI. Mineral Manures — Bones, and What They Taught Us — Sulphuric Acid and Nitrate of Soda — Bone Ash — Animal Charcoal, or Bone Black — Bone Meal — Sulphate of Ammonia : Its Great Power of Decomposing Other Manures — How to Detect Impure Nitrate of Soda — Nitrate of Potash, or Saltpetre — Phosphate of Lime — River Phosphates — Canadian Phosphate — A Ridiculous Extortion 57 CHAPTER XII. Sulphur — Its Occurrence in Nature — The Mines of Sicily — The Refining Process — Iceland Soufrieres and Solfataras — Use of Sulphur in Man- ufacture — Pyrites and How They Occur — Analytical Tables — General Annual Consumption — The Mines of Spain Described 69 CHAPTER XIIL Sulphuric Acid Manufacture — Sketch of Its Past History — Pyrites Burn- ing ■:— Glover's Towers — Hints on the Construction of Leaden Chambers — Chemistry of the Process — Denitration — Gay-Lussac Towers — General Remarks 75 CHAPTER XIV. Superphosphates — Uncertainty of Their Composition — Their Manufacture Described — How to Manipulate When Made — Nature of the Decom- position Process — Explanation of the Loss in Weight — What is Soluble Phosphate ? — Discussion of Its Merits in the Field — Its Ac- tion in the Soil — Necessity for Careful Analysis Made Further Manifest — Precipitated Phosphates : Their Manufacture, Their Virtues and Superiority — LTse of Complete Manures, with Examples and Statistics — Remarks on Home-made Chemical Manures 80 CHAPTER XV. Chemical Analysis — How to Read and Understand Chemists' Certificates — Use of " Complete " and " Simple " Manures — Conclusion 89 MODERN HIGH FARMING. CHAPTER I. 6ENEKAL rNTRODTJCTORY REM.VKKS INFLUENCE OF CLIMATE ORIGIN OF SCIENTIFIC AGRICULTURE ITS PROGRESS IN AMERICA. "77 GRICULTXJRE may be truly said to be the foundation stone II or roclc upon whicli is built every nation's riches, since the qJ productions of nature are the materials of art ; and it is un- deniable that the prosperity of the whole human race has always been dependent upon three powerful physical agents — Climate, Soil, and Food. The first thing necessary to the cultivation of a community is wealth, as without it there can be no leisure, and without leisure no opportunity for the development of the intellectual faculties and the acquisition of that knowledge upon which the progress of all civili- zation depends. As will be shown by a very brief retrospective examination, the rapidity with which capital is accumulated in a new country must vary in accordance with the nature of its climate and the fertility of its soil — the latter regulating the returns made to any given amount of labor and care, the former regulating the energy and the conti- nuity of that labor. The only portions of the American Continent which could lay any claim to civilization before the appearance of Europeans, were 6 MODERN HIGH FARMING. those comprised in its very hottest parts — the tract which stretches from the Isthmus of Panama to Mexico in the northern, and to Peru in the southern tropic. If we momentarily set aside — to be dealt with later on — the questions of geological and chemical varieties of soil, we may at once assume that' the two regulating causes of fertility are combined heat and moisture — the f ruitfulness or sterility of the land being dependent upon their abundance or deficiency. Now as regards moisture, neither in North nor in South America does one great river empty itself into the Pacific — the whole of them being upon tlie eastern coast ; and as regards heat, nature has been equally partial in its endowment of the west. Whether the natural differ- ence of temperature resulting from this curious phenomenon forms part of some universal scheme, or whether we are dealing with a pe- culiar instance, we will not stay to discuss ; the fact and its influence upon the early history of this country are indisputable — the two great conditions of fertility not having been naturally united in any part of the entire continent north of Mexico. The primitive inhab- itants were, therefore, in this diflaculty: on one side they wanted heat, while on the other they had no irrigation ; and the result was that until the sixteenth century, when the acquired knowledge of Europeans was brought to bear upon the difiiculty, there existed no agriculture, no accumulation of wealth, and no progress north of the twentieth parallel, even toward that rough civilization so easily attained by the nations of India and Egypt. For a direct contrast to what went on in the north, we have now only to turn to the narrow tract of land lying south of the twentieth parallel, of which the peculiar configuration caused by the contraction of the continent until it reaches the Isthmus of Panama — secures to it a large extent of coast. This southern part of North America thus assumes the character of an island — with that feature of an insular climate, t'je increase of moisture consequent upon the watery vapor arising from the sea, and the augmentation of rainfall natural to its vicinity. It was therefore the only portion possessing a natural combination of the MODERN" HIGH FARMING. 7 two essential elements — its equatorial situation giving it heat, and the shape of its land humidity; and it was also the only portion which arose out of barbarism. Without going so far Back into the history of this country for ex- amples in favor of our argument, we need only have turned to the sandy plains of California, where, until they were quite recently sub jected to irrigation by the ingenuity, enterprise and enormous capi- tal of a civilized community, nothing met the traveler's mournful gaze but the contemplation of a sterile desert; but where are now displayed all that marvelous exuberance of soil that has never failed to characterize a virgin country when the natural physical elements have not been wanting. It would be useless in such a work as this to attempt to trace the progress of agriculture back to the wandering husbandmen who roamed from place to place with their immense flocks until, by the eventual adoption of a fixed abode and the expenditure of time and labor, a certain price or value was accorded to their land ; and we must therefore content ourselves with the broad statement that un- til long after the commencement of the present century the agri- cultural arts, as practiced by the most advanced of the European communities, differed but in trifling details from those exercised by the ancient Romans and described in Columella's great work ' -De Re Rustica." Alarmed by the falling off of crops and general signs of the ex- haustion of their soils, the European scientists have been moved to bring to bear upon the question the acquired knowledge of the geologist, botanist and chemist, and to such men as Liebig, Lawes, Gilbert, Dumas, Boussingault, Barral, Malagati, Payen and George Ville we are now indebted for a progress which has enabled us to become almost independent of natural causes, and for a literature of applied and applicable truths second to none in value and importance throughout the whole range of scientific investigation. That a goodly number of intelligent American agriculturists have awakened to all this, and have long been following in the foot- steps of their European brethren, is proved by the extension of 8 MODEEN" HIGH FARMING. sulphuric acid and fertilizer manufacture in this country ; but there still remains an immense majority of farmers great and small, high and low, in north, south, east and west, who have made no study of scientific agriculture ; who have not kept pace with the times ;• who even look with suspicion and distrust upon those who would enlighten them ;' and who are to-day unable to understand why their annual crops, though perhaps rotatory, are no longer so abundant, nor of so good a quality as they were wont to be thirty or forty years ago. Ours being essentially an age of thought and progress, the time has come when every man must realize that agriculture can only remain a profitable pursuit, on the condition of yearly obtain- ing from every acre a maximum and cheap return, and that in order to succeed in this he must restore to the soil those elements which it once contained, but which in the process of nourishing the plants, have been absorbed and taken away. CHAPTER II. TnEOUY OP SCIENTIFIC AGRICULTURE FORMATION OP THE GLOBE ITS TEMPERATURE COMPOSITION OP THE EARTH ITS PRINCIPAL ROCKS CIIEJnSTRY OP VEGETATION NECESSITY FOR GEOLOGICAL KNOWLEDGE REMARKS ON DRAINAGE AND IRRIGATION. The theorj' of scientific agriculture is based upon a complete knowledge of the nature of soils, plants, animals and manures, and it is evident that until these elements are thoroughly understood, no attempts at improvement or plans for increased production can possibly be successful. It is curiously illustrative of the general ignorance that very" few people know anything of the earth they tread or the soil they cultivate, in what way it was formed, or what is its composition. How, then, can they imagine the mighty in- undations and the terrible upheavals ? How conceive anything of that gigantic disemboweling of the earth - monster, and of the awful torrents of burning lavas which it has vomited forth ? Can they realize that our tallest mountains, even those which from their )ieight are covered with perpetual snow, were once submerged in rolling seas ? or that the rocks and cliffs we meet with in our plains are nothing more than agglommerated masses of organisms that swarmed the waters ? We might very easily allow ourselves to be carried far away by this seductive topic, but must needs confine our pen for present purposes to a brief synopsis of elementary facts which, if they serve no other uurpose, may induce some of our readers to "seek for more." 10 MODERN" HIGH FARMIN"G. Geologists agree in supposing that our globe was once a glowing mass of fire, that the formation of the earth's crust is due to the gradual process of cooling. They point to its figure and compare it to that of a liquid rotatory body acted upon by gravity, and from this deduce evidence of its original fluid state. The volcanoes actually in a state of eruption prove the earth to have an internal temperature independent of the heat of the sun ; and from observations made in the deepest mines all over the world, it would appear that this tem- perature, below a depth of one hundred feet, increases 1° Fahrenheit in every twenty yards; so that, presuming the rate of increase to be constant, at twenty thousand yards we should arrive at a low red heat, and by descending still lower, this would be sufficiently in- creased to maintain all kinds of minerals in a state of fusion. The different species of rocks of which the earth is composed, may be divided into three groups. First— SANDSTONES. — These belong to every geological period, are sedimentary and of infinite variety, though differing only in the size of the grains of which they are composed and in their degree of texture and compactness. When occui'ring in connection with clays, marls, chalks, iron-ores, glauconite, or felspar, in varying proportions, they undergo transformations which convert them into vegetable soils. Second— LIMESTONES. — These are organically formed rocks, made up of the remains of animal life, corals, shells and bones, cemented and so intimately bound together as to neces- sitate the minutest investigation for their recognition. Third— GRANITE. — These are igneous rocks, of volcanic origin, and owe their formation to the cause of interior heat. They are composed of numerous distinct orders of crystals such as felspar, mica, gneiss, quartz and hornblende, mixed up and not in regular beds. The history of these three great groups of rocks may therefore be aptly termed the history of the earth, since their decomposition un- der the combined influence of the atmosphere and water, during a MODERN" HIGH FARMING. 11 long period, ultimately produces highly fertile soils containing sili- cates of aluminum, potassium, sodium, magnesium, iron, phosphates, sulphates, and chlorides. The soil at first resulting from this gradual decomposition forms very thin layers, in which only the lower orders of plants find suflS.- cient food to fructify — deriving from the air and the rain their carbon, hydrogen, oxygen and nitrogen. In the natural process of death and decay, these fresh elements of fertility — in various states of combination — are transferred by the plants to the soil, which is thus enabled to afEord nourishment to a higher vegetation, and, by at- tracting to it the animals in search of vegetable food, receive from them other elements conducive to the highest fertility. The study of Geology — even if only elementary — will therefore enable the agriculturist to accurately guage the natural resources of his country, and will teach him how to adapt his ideas upon drain- age, irrigation, plowing and sowing to the surrounding circum- stances of soil and climate. He will learn to mix and combine differ- ent soils, and understand that certain overlying beds on his lands may not at all resemble in composition or be derived from the under- lying rocks, but may have been carried from immense distances and deposited by water. Then it may frequently happen that in some fields he may have a very stiff and unworkable clay — which his geo- logical map would show to repose upon a deposit of sand or of lime- stone, aad in such a case he could at once (after previously verifying the fact by some preliminary boring or deeper ploughing) open up a quarry and supply his clays with the necessary elements for their conversion into loam. The acquirement of knowledge will naturally induce us to seek by art to assist or even to improve upon nature, and well-considered preferences will be accorded to certain cultures and breeds of cat- tle, while into the soil will be introduced those elements of fertility in which it has been proved to be deficient. Sufficient attention will be paid to drainage, the necessity of free- ing the land from an excess of water being even greater than the introduction of fertilizing elements ; for, although under proper con- 1:2 MODEKN moil FARMING. ditious the latter will uudoubtedly increase the ixuautity ami value of the crops, too much AAater ■will effectually preveut us from draw iiig any crops at all. Nothing, therefore, can ever be done with laud anywhere, if it be not properly drained where there is too much moisture, or properly irrigated where the uecessary natural water supply is not forthcoming. It is because of the vital importance of this question that we are thus emphatic at this early stage . To ascertain whence such an excess of water proceeds is not by any means a matter of difficulty; a very damp climate, a spongy and retentive soil, the existence of underground springs- all these or any of them may be the causes of disastrous eHects, which can be easily remedied by those possessed of suth knowledge as we have endeavored to describe. In the lirst of the cases named, the evil may be overcome by ordinary surface drainage, but in the second, it is only after ascertaining the true composition of the soil, that we can cll'ect such mixtures with other soil, or conibinations with lime or sand, as may suggest themselves as necessary, while in the third case, the construction of deep luulerdrains alone will carry off the water from the sub-strata without allowing it to reach the surface. AVherever there exists a faulty or careless system of drainage, no correct estimate of the agricultural value of a property can possibly be formed, for although from its excessive dampness a soil may remain unproductive, it may, nevertheless, contain all the necessarv elements of fertility. CHAPTER III. MINERALS NECESSARY AND INJURIOUS TO PLANT LIFE — — HOW PLANTS ABSORB TUEIR FOOD THE OASES AND THEIR VARIOUS TRANSFORMATIONS NITROGEN PHENOMENON OF NITRIFICATION IN THE SOIL SOURCES OF NITROGEN ITS MANUl'WCTURE ITS FIXATION ITS ASSIMILA- TION THE NECESSITY FOR ITS ARTIFICIAL APPLICATION AS MANXJRE. The presence of a considerable number of mineral substances in the soil is essential to the healthy growth of plants. But, while some of these minerals, such as magnesium, manganese and fluor, take no part in furthering, others are positively fatal to their de- velopment. Thus one per cent, of sulphate of iron will render a soil unproductive, and instances are not wanting where one per cent, of chloride of sodium (common salt), in very dry regions, has killed all vegetation and produced sterility. We may therefore consider that the principal essential substances demanded by a healthy and robust plant life, are the following : First. — Oxygen, hydrogen, carbon and nitrogen, which veg- etables take in and assimilate from the air, through their leaves or respiratory organs . Second. — Phosphorus, potassium and lime, contained in the soil and absorbed by their roots. Commencing with the three gases — oxygen, hydrogen and carbon- ic acid, we find that they exist in abundance, both in the air and in the soil. A combination of the two first in the form of rain, dew, springs or irrigation, burnish, with the carbonic acid, the necessary 14 MODERN^ HIGH FAKMIXG. elements to form the carbou-bydrates — glucose, cellulose, dextHne and starch, or the hydro-carbons — oils, fats, essences and resins. Carbonic acid gas exists in the atmosphere in the proportion of four lO.OOOths, and is an union of carbon and oxj-gen formed by combustion, respiration, or fermentation. All kinds of fuel con- tain largo proportions of carbon, which, combining with the oxygen of the air in the burning process, makes its escape in the form of car- bonic acid gas. In the course of his experiments Boussingault discovered that while under the influence of light, the leaves of plants absorb and decompose this gas, and that in the dark they evolve or give back a certain portion of it. Nitrogen is very generally supposed to be assimilated either as nitric acid — a combination of nitrogen, hjalrogen and oxygen, or as ammonia — a combination of nitrogen and hydrogen only. But the question is a most difficult and vexed one, which has created a vast amount of speculation and upon which very few of our best authorities have yet been able to agree. A great many of our readers will have doubtless seen performed in their school-days, that interesting experiment first shown by Cavendish in 1786, demonstrating the formation of nitric acid from the combination of the oxygen and nitrogen of the atmosphere, under the influence of the electric spark. The presence of minute portions of nitric acid and of nitrates in the rain water, snow, and hail, is easily explained on the theory of this important discovery, and any donbts which may have existed in some minds as to the reality of the combination, were eftectually and finally dissipated when 51. Clo^z publicly performed the following experiment in the course of a lec- ture deliA-ered to the Chemical Society of Paris, in 1861. A mixture of hydrogen and oxygen gases was burnt in the presence of nitrogen, and about 210 grammes of water resulted from the explosion, which, upon evaporation, was foiTud to contain 3 grammes of salt- petre. Xumberless chemists have since that time devoted their attention to tlie problem of lixing the nitrogen of the air in some utiliza- MODEKK HIGH FARMIKG. 15 ble and assimilable form, aucl many of them lay claim to successes which, although theoretically correct ami practically realizable in the laboratory, have never yet been able to stand the test of econom- ical industrial application. This great question will eventually be satisfactorily solved, for we have already witnessed the remarkable phenomena of the forma- tion of nitrates by the mere passage of atmospheric air through such porous bodies as pumice stone and chalk, previously impreg- nated with an alkaline solution. It is therefore highly probable that the new compound of nitrogen will be ammoniacal, coinmercially presented in the form of sulphate, and that the costly product now used and manufactured from the refuse liquors of gas works, will give place to an article of which the price will be comparatively nominal and the supply inexhaustible. Until the efforts now being made, however, in all countries, are crowned with success, it behoves us to carefully turn to account all those sources of nitrogen actually at our disposal. That the com- bination of nitrogen and oxygen to form nitric acid actually goes on in the air, we have said enough to prove, and that a similar operation is possible in the soil we can just as easily show. In this case the chemical action ensues under the influence of the slow combustion of the carbonized or decaying matters, left behind them by the crops, or by the leaves which have fallen from the trees and been worked into the ground. Now, were it possible for us to allow an exhausted field to remain uncultivated for a given number of years, abandoning it to that wild and spontaneous vegetation and subsequent death and dec&j, which would naturally take place; we should discover that the soil had absorbed such a quantity of nitrogen, as to permit of our reaping large and repeated crops of cereals without any artificial introduction of this essential element. But, as this course is diametrically opposed to all the rules of rational culture, and would in the majority of cases be impracti- cable, we cannot for a moment entertain it as a serious remedy, and must seek in other directions that which instead of necessitating the 16 MODERK HIGH FARMI]SrG. Stoppage of any portion of our culture, will enable us to vastly increase, if not more tlian double our yearly production . Having shown that nitrogen can only enter into combination and be fixed in the presence of combustion, no better agent for helping this process can well be imagined than farm-yard manure, of which in a subsequent chapter we shall have a great deal to say. Ploughed into the field, this decomposed, rotting, or carbonized mass attracts the nitrogen during the whole course of its carboniza- tion, and having fixed it, enables it subsequently to undergo the various transformations which render it assimilable, and allow of its passing from the soil into the plant. In what form vegetables assimilate the nitrogen thus fixed, it is very difficult to determine ; nor do any of our best authorities seem to agree upon the issue. Our own opinion, based upon the phenomenon of nitrification and the constant formation of nitrates in the soil, is that the nitrogen absorbed into the saj? is brought into contact with the oxygen set free by the decomposition of carbonic acid, and thus forms nitric acid, which penetrates into all the tissues. It may be urged against us that plants are organs rather of re- duction than of oxidation, and that the nitric acid itself would — undergoing a decomposition similar to that of carbonic acid and water — be transformed into ammonia by the hydrogen then being produced ; but our own researches have been sufficiently elaborate to justify us in the meantime in maintaining our ground. That nitrogen is assimilable in its free and natural state, we posi- tively refuse to admit, and, although it forms four-fifths of the vol- ume of atmospheric air, and exists in appreciable quantities in the soil, only an insignificant portion would, in the absence of all com- bustion, be available for the nourishment of the plants. Presuming, therefore, that carbonized materials of any kind are not sufficiently abundant to well cover the ground after each crop — and this is generally the case — we have to bear in mind that we continually take away large quantities of nitrogen, which MODEKN HIGH FAKMING. 17 unaided nature does not with sufficient rapidity replace. It is consequently necessary to artificially introduce it into the soil in some cheap, efficacious and soluble form, if we desire the equilibrium to be undisturbed, since its presence determines the dearth or abundance in the plants of nitrogenous carbon-hydrates or proteids, such as legumine or vegetable caseine in the leguminous species, gluten in the cereals, and nicotine in tobacco. As at a later stage of this work we shall come back to this question under the heading of Manures, we may for the present leave the gaseous elements and pass on to those of a mineral nature, which play a no less important part in the vegetable economy. CHAPTER IV. PHOSPHATES DISCOVEKY OF THEIR ACTIVE PRINCIPI.E USE OF BONE MANURE DISCOVERY OF MINERAL PHOSPHATES HOW THEY OCCUR IN NATURE THEIR FORM IN THE SOIL, HOW THEY ARE M.UDE SOLUBLE HOW THEY ARE ASSIMILATED BY PLANTS MIGRATIONS OF PHOSPHORUS THE NECESSITY FOR ARTIFICIALLY INTRODUCING PHOS- PHORIC ACID AS MANURE. Of the absolute necessity for the presence in the soil of such min- erals as phosphorus, potassium and lime, we have the most undeni- able proofs ; for it has been clearly shown that vegetables, though abundantly supplied with oxygen, hydrogen, carbon, and nitrogen, remained puny and devoid of vigor if deprived of mineral salts. The form in which phosphorus is assimilated is that of phosphate — produced, tirst by the action of oxygen as phosphoric acid, and then by the combiuation of this acid with various bases, the principal of which is lime. Enormous deposits of phosphate of lime have been and doubtless will continue to be discovered in every quarter of the globe; and as, besides being an essential to plant life, it is the princi- pal constituent of bones, we may assume that, if by some extraordi- nary jihenomeuon its source were suddenlj' cut o& or exhausted, all vegetable and animal life would come to an end. So for back as the year 1698 a celebrated French engineer— Yau- bau — writing in the Dime Boi/al, says : "We have for a long time past been universally complaining of the falling olf in the quantity and quality of our crops ; our tarms are no longer giving us the i-eturns we were accustomed to ; MODEEN" HIGH FAEMIKG. 19 yet few persons are taking the pains to examine into the causes of this diminution, which will become more and more formidable un- less proper remedies are discovered and applied. " Despite this warning note, it was not until after the co mmence ment of the present century that the English farmers began to use crushed bones as a manure, and even then they did so in blind ig- norance of the principles to which they owed their virtues, as is clearly shown by an article published by one of the scientific papers of that day — 1830 — in which the writer says : "We need take into no account the earthy matters or phosphate of lime contained in the bones, because, as it is indestructible and insoluble it cannot serve as a manure, even though it is placed in a damp soil with a combination of circumstances analytically stronger than any of the processes known to organic chemistry." A subsequent writer upon the same subject declares that "bones, after having undergone a certain process of natural fermentation, contain no more than two per cent, of gelatine, and as they derive their fertilizing power from this substance only, they may be cou- ■sidered as having no value as manure." That such opinions as these should have prevailed only fifty years ago seems to us all the more preposterous, because of the gigantic strides which we have made since then, and because of the singular fact, that even the Chinese were better informed than our grand- fathers, inasmuch as they knew that the fertilizer was a mineral principle, and for many centuries have used burnt bones as manures. Despite the unflagging researches of the best men of the time, it was not until the year 1843, that the Duke of Richmond, after an exhaustive series of experiments upon the soil, with both fresh and degelatinized bones, came to the conclusion that they owed their value, not to gelatine or fatty matters, but to tlieir large percentage oj phosplioric acid ! The spark thus emitted soon spread into a flame, and a conclusive experiment shortly after published by the illus- trious Boussingault, set all uncertainty at rest forever. Numerous species of vegetables were planted in a soil rich in as similable nitrosen, and absolutely devoid of any trace of phosphoric 20 MODEEN HIGH FARMIISTG. acid. No development of these plants took place, until he had made the addition of phosphate of lime, when their growth iecame flourishing ! ! ! Meanwhile large workable deposits of mineral phosphates were already known to exist, they having been simultaneously discovered in their respective countries, by Buckland in England, and Berthier in France ; and ih the course of a lecture delivered to the British As- sociation in 1845, Professor Henslow, describing the Suffolk copro- lites, suggested the immense value of their application to agriculture. From this time may be dated the commencement of phosphate mining, and it is certainly marvelous to contemplate, not only the rapidity with which fresh deposits have been everywhere discovered and opened up ; not only the millions of tons yearly raised to sup- ply a never-failing demand, but also the fabulous amount of capital and gigantic numbers of workmen constantly and remuneratively employed in the production. Phosphates of lime have been found in rocks of all ages, and of nearly every texture ; sometimes pure ; sometimes in different forms of chemical combination ; in mineral fissure veins ; in pock- ets, or filled-up cavities ; in stratified beds or layers, and in intimate connection with the fossil remains and other phosphatic matter, de- posited by the ancient seas. They are, however, chiefly found as: APATITES, or Crystalline Phosphates, occurring in the gneissic rocks of the Laurentian age in North America and Norway, and in the Silurian rocks of Spain and Portugal. COPROLITES, or Fossilized Nodules, occurring in the green sand- stone, or cretaceous rocks of England, France, Belgium and Russia. PHOSPHORITES or Amorphous Rock Phosphates, occurring in the Tertiary stratas— principally in France, Germany, and America (South Carolina). Their commercial value is entirely based upon their strength in tri- calcic phosphate, which ranges in some regions and for some mar- kets, from 30 per cent, up to 85 per cent. All those who are familiar with soil analysis will agree that, in the majority of cases, the phosphates therein are found to exist as MODERN" HIGH FAEMING. 21 phosphates of sesquioxide of iron, or alumina — insoluble in carbonic acid, but readily decomposed by the alkaline carbonates. We can therefore admit that, under the influence of a well-limed soil, or when acted upon by the carbonates resulting from the decomposi- tion of the felspar rocks, these insoluble phosphates should yield their phosphoric acid, to be taken up in solution by water ; either pure or charged with carbonic acid, and that in this form they should be absorbed with the water by the vegetable roots. In the springtime, phosphates are found in noteworthy quantities in young organs of plants, especially in the leaves, but the quantity gradually diminishes as the plant approaches maturity, until when the blossoms appear, the phosphates are found to have entirely quit- ted the leaves and accumulated in the seeds. This is the cause of that peculiar effect, which has long puzzled farmers, that fodder cut and brought in after the period of maturity, proves to be much less nourishing to the cattle than that cut before this period has arrived. It is worthy of note that in every instance, this displacement of the phosphates is accompanied by an equal disx)lacement of the nitrogen, and all those who have made successive analyses of grains in different stages of maturity, must have been struck by the regular parallel man- ner in which the quantities of both have progressively augmented. Mr. Corenwinder, in his work upon the migrations of phosphorus in vegetables, alluding to this phenomenon remarks : "It has long been known that young buds are rich in nitrogenous . matters, which are always accompanied by a relatively considerable portion of phosphorus, and there is no doubt that these two elements are united in the vegetable kingdom according to some mode ot' combination which is yet a mystery. " And Mr. Boussingault, writing upon the same subject, says: "We perceive a certain constant relation between the proportions of nitrogen and phosphoric acid contained in foods, those being rich- est in the latter element which contain most nitrogen. This would appear to indicate that in the vegetable organization phosphates particularly belong to the nitrogenous principles, and that they fol low the latter into the organization of animals," 22 MODEKK HIGH FAKMI^STG. Now we have seeu that nitrogen can, though in a very small degree, be really imparted to plants and to the soil from the atmos- phere ; and that after having assisted, through the plant, in forming the muscular tissues of the various animals, it is apt to reassume its aerial character and become at liberty to form fresh combinations either as ammonia or nitric acid. The actual loss, therefore, of this element is comparatively small ; but with the phosphorus the case is a very different one, since it always maintains certain fixed combi- nations, and is taken away from and irrecoverably lost to the soil in immense quantities with every crop. Hence the same question arises here which, as we have seen, arose in the case of the nitrogen, and none are more important or more worthy of profound consideration : "How SHALL WE KESTOKE TO THE GROUND THOSE ELEMENTS WHICH WE YEARLY TAKE AWAY FROM IT ?" It will be our duty, later on, to j)oint out the solution which science has furnished to this problem, and how the remedies it pre- scribes are to be employed with economy and profit. CHAPTER V. POTASH : ITS ACTION ON THE SOIL IS IT ESSENTIAL TO PLANT LIFE ? RESULTS OF DIRECT EXPERIMENTS ITS NECES- SITY MADE CLEAR SOURCES OF ITS SUPPLY LIME THE LIMING OP SOILS ITS CHEMICAL ACTION ITS AB- SORBING POWERS ITS ACTION ON SULPHUROUS ORES ITS ACTION ON IRON ALUMINA AND PHOSPHORIC ACID IN THE SOIL NECESSITY FOR ITS ABUNDANT USE. The ashes of all plants, when submitted to analysis, are found, to contain potash in noticeable proportion, and hence that substance is presumed to be a very active and essential fertilizing agent, although its precise influence in the process of development is not rig- orously known. It has been suggested that, once in the soil, it enters into a solu- ble combination with the phosphoric acid to form potassic phos- phate, and in that shape becomes absorbed by the roots of the plants, the basic salt, however, remaining deposited in the various organisms after the evaporation of the water. The doubts which have been expressed by many authorities as to the utility of introducing potash into the soil as an active artificial manure, induced Monsieur George Ville, when experimenting at Vincennes, to devote his particular attention to this disputed point, and although it cannot be said that his researches have added very much to our information from a chemical point of view, the results he obtained were of a sufliciently definite nature to warrant us in be lieving that the growth of plants would be unhealthy, if completely deprived of potash. 24 MODERN HIGH FARMI^STG. On the one half of a completely exhausted field, plentifully man- ured with nitrogenous and pliosphatic fertilizers, he caused to be sown a sufficiency of the finest quality grain. This sowing produced a crop of extreme poverty. On the other half of the same field to which the same manure had been applied, but with the addition of potash, he sowed exactly the same quantity and quality of grain, and produced a crop of mag- nificent appearance and extreme abundance. Exactly similar results have attended many experiments of our ovi^n upon plants of the leguminous species, and it therefore seems evident that due weight must be attached to the opinion of those who affirm that putting back potash into the soil, is quite as necessary in some cases as the addition in others of phosphate of lime. We must not overlook that we have not yet penetrated into all the mysteries of plant life and plant feeding ; that many things daily occur which overthrow or considerably shake the conclusions we had already formed and the theories we had built upon them ; also that results obtained in some regions and by some agencies are often dia- metrically opposed in other places, although the surroundings appear to be the same. We should, therefore, carefully guard ourselves against the adop- tion of those extreme views which have prompted some excellent chemists to teach us that potash has no merits as a manure, and which have induced others to assert that no perfect crops can be pro- duced without its active intervention. Joining our own experiences to those of many important agricul- turists in France and England, with whom we have corresponded on the subject, we are content to endorse the opinions of George Ville ; and to look upon the use of potassic salts as highly beneficial, if not indispensable. The principal commercial sources of our potash are the mines of Stassfilrt, Germany, where in the various forms of sylvine, kainit, and carnallite, it was discovered in 1858 in proximity to the beds of chloride of sodium (common salt). We generally meet with it as a MODERlSr HIGH FARMING. 25 tolerably pure muriate or chloride, aud in this form recommend its addition to manures, or direct introduction into the soil. If the utility and action of potash are sometimes contested, the same cannot be said of lime, than which few elements in agriculture play a more iniportant part, or one that is better understood. The liming of soils has been a common practice in all countries from the veiy earliest times ; but it was presumably not until the seventeenth century that the use of burnt lime — now universally recommended — was introduced. It is employed in quantities vary- ing with the composition and the requirements of a soil, from twenty tons per acre into those which are heavy, compact, and laden with moisture, to five tons per acre into those which are light and of a dryer nature. That its scope of usefulness cannot be by any means guaged by the relatively small proportion found by analysis to exist in the plants, we must all agree, and we have often asked ourselves whether in point of fact, the presence of this element in plant organisms is directly connected with their nourishment and growth, or whether it is to be explained by the mere evaporation of the water by which it was conducted into the tissues and there deposited ? However this may be, the quantity absorbed from is out of all proportion to the quantity introduced into the soil, as will be seen from the following figures. Quantity of Lime absorbed jjer acre by the u7idermentioned Cultivated Plants : Potatoes, 7 lbs. Wheat, 20 lbs. Beetroots, 18 lbs. Clover, 70 lbs. And it is therefore not in this direction that we have to seek for its principal chemical action. In certain regions pyrites, or sulphurous ores, are disseminated throughout the soils and underlying strata, sometimes in large but generally in minute quantities. The action of heat upon these sul- phur-bearing substauces generates sulphurous vapors, and these on meeting the elements undergoing the process of nitrification — already 26 MODERN HIGH FAEMIKG. ready described — would form sulphuric acid, which, combining with the oxides in the soil to form sulphate of iron, would immediately render cultivation or vegetable growth impossible. The counteracting or preventive part here j)layed by lime is at once manifest, since by its ready absorption of the acid it would in- terfere with any. other combination and become, itself, more soluble and efficacious by its transformation into gypsum. Apart from such special cases as these, the virtues of lime must be attributed to its caustic action upon all organic remains. Being rich iu unavailable because insoluble forms of nitrogen, these are rapidly decomposed, and by coming in contact with other agents are submitted to the nitrification process and rendered assimilable) and this has given rise to the assertion that to spread lime upon a newly plowed cultivated field is equal to the application of a good dose of soluble nitrogenous fertilizer. As we shall jjresently show, its intimate admixture in a finely powdered state with all kinds of clayey soils is invaluable^ diminish- ing as it does their plasticity and augmenting their permeability to the action of air and water. We have explained that phosphoric acid invariably exists in the soil in combination with peroxide of iron or alumina ; these two agents must therefore exercise an immediate transforming action upon the phosphate of lime which is introduced in both natural and artificial manures. This transformation can be demonstrated by adding either per- oxide of iron or alumina, or both, to a solution of phosphates iu water charged with carbonic acid gas (ordinary seltzer water at high pressure), when in a very short time all the phosphoric acid will have disappeared from the solution, and be found iu the deposit as phosphate of peroxide of iron. Now, if one gramme of this ferric phosphate be put into water with two or three grammes of carbonate of lime, and be allowed, with frequent shakings, to stand for forty eight hours — the mixture at the end of that time being poured into an excess of seltzer water — MODEEX HIGH FAEMIN'G. 27 the solution will be found upon analysis to contain about six milli- grammes of phosphoinc acid. The results of these experiments are too clear to permit of our doubting that the lime put into the soil becomes carbonate by its absorption of the carbonic acid gas, and that in tliis form it is chiefly instrumental in decomposing the phosphates of iron and alumina. It is therefore necessary to furnish the soil with a considerable excess of lime, since if the free peroxides maintain -the ascendant, no effect will follow the application of the phosphates, from the simple fact that their dissolution cannot take place. CHAPTER VI. now SOILS LOSE THEIR NITEOGEN TABLE OF PROPORTIONS NECESSITY OF SOIL ANALYSIS TABLE OP PHYSICAL ELEMENTS AND CHEMICAL CONSTITUENTS. We Lave now reviewed the nature of the principal elements essential to vegetation, and have described the parts they severally play and the places they probably occupy in the organisms of plants. While admitting that, in some insignificant instances, we are still unable to completely unravel the mysteries connected with vegeta- ble inner organisms, we may claim to be no worse off in this respect than the science of Pathology, to whose professors many secrets re- lating to the blood have still to be revealed. We have nevertheless been able to place on record a series of facts which support our theo- ries and confirm our deductions ; and facts, as we are all aware, are "very stubborn things." Thus, with man, it is not enough to give him food : his diet must contain a mixture of substances, the absorption of which is the con- dition of his existence, and whose composition is found to be iden- tical with the materials constituting his bodily frame and tissues. In plants the same phenomenon presents itself : deprived of cer- tain elements they pine, droop, and die ; supplied with them they flourish and are vigorous ; and, upon analyzing their organism, we prove them to contain an abundance of the very elements without which they were unable to exist. It will be interesting here to examine some figures showing us in what proportion the soil is regularly deprived by the different crops of its nitrogen, phosphoric acid, and potash. MObERK HIGH PARMilsrG. ^9 Table showing the approximate quantity by weight in POUNDS of nitro- gen, phosphoric acid, and potash, taken from the soil by every ten TONS of the following crops : Grains and Seeds. Eye . .. 420 ...311 138 Barley ,.. 385 ...180 122 Oats ... 490 ...133 91>^ Corn ... 405 ...135 81^ Colza ,.. 785 ...415 220 Linseed ... 810 ...320 257 Hemp ... 6C0 ...437 242 Poppy . .. 650 ...420 184 Peas ... 850 ...221 260 Vetches .. 1010 ...203 160 Horse Beans ... 990 ...297 310 Lentils .. 900 ...135 205 Lnpine ...1380 ...221 293 Fodders. Meadow Hay ... 335 ...90 410 White Clover ... 605 ...220 265 Eed " ... 532 ...145 495 Luzerne ... 580 ...132 383 Vetche Hay . . 595 245 780 Straws and Stalks. Wheat Straw ... 86 ...02 127 Eye " . . . G-3 ...40 197 Barley " ... 132 ...46 ........ 240 Oats " ... 94 ...52 197 Com " ... 133 ...98 410 Pea " . .. 205 . .. 410 T9U 98 .... 271 Horse Beans ...120 655 Colza " . . 65 250 Linseed Stalks.. . .. 192 ...lie 300 Hemp . .. 207 . . . 135 140 Flowers and Leaves. Hop's Cones ...22.33 ...1203 "37 568 Tobacco Leaves.. ...247 1308 Roots Beets .. 40 . .. 84 . . . 31 98 Potatoes ...40 142J^ Turnips , .. 52 .. 55 ...35 83 Carrots ... 33 84 30 ■ MODERN" HIGH FARMING. No better arguments can possibly be adduced in favor of soil re- constitution, than the figures here given ; for they seem to us to be a direct appeal from the plants themselves, for the administration of that food without which they must gradually starve and finally dis- appear. "We have, therefore, to study with increased earnestness that problem which has already been so long occupying the minds of agricultural scientists; the question of "how we are to arrest the marked falling off in the quantity and quality of our crops, by the impoverishment and gradual exhaustion of our soils ; and how, where, and when we are to apply those elements of fresh vigor and life, which the discoveries of chemistry have placed at our command. When a man who has hitherto never been sick, finds that his health is beginning to fail, he, if possessed of common sense, calls in his doctor, who after careful diagnosis discovers the root of the evil and prescribes a remedy. Is it not evident that if he would know what to do for his soils to make them productive or amenable to culture, or to restore them to their past state of fertility, the farmer should first of all be made acquainted with their composition — their physi- cal and chemical properties? We have ever advocated the theory exposed at the commence- ment of tills work, that no successful results can attend any attempts at scientific culture, if such attempts are made in ignorance of the elements we seek to improve ; and for this reason we maintain that the only certain guide to successful cultivation, is the complete chemical analysis of the soil, joined to a thorough knoioledge of the eli- matological and other surrounding conditions. With these at his com- mand, the experienced chemist can throw the broad light of day on all the points which have been hitherto obscure, and can suggest methods of practical treatment, at once productive of a radical amelioration. It has been and still is urged in some quarters, that no informa- tion procured in the laboratory, can be so perfect as that acquired by constant observation on the ground, and by continuous practical manipulation of the soil ! MODEKN" HIGH EARMIN"G. 31 We reply to this that, while quite prepared to accede in the very fullest manner to all the claims of long practice, and while admitting that some crops may be annually produced, it has frequently occurred in our experience that the addition of some essential ele- ment to the soil, discovered by chemical investigation to exist there in InsufEicient quantity, has been the means of immediately doubling the quantity previously produced of those very crops and greatly height- ening their quality. Thus, for example, it is very desirable to know how much lime a soil contains, since the different combinations which it facili- tates or into which it enters, produce sweet, sound and nutritious green crops, full eared grain, and fine strong straws. If a soil con- tain too little or no lime, none of these advantages can accrue, and yet the farmer may have expended considerable sums in the purchase of other fertilizers, and will not comprehend their inefSciency until his attention is directly called to the absence of lime. Again, it is necessary to know the proportion of combustible or organic matter contained in a soil, since upon their abundant pres- ence depends the fixation of a greater or lesser quantity of nitrogen. And yet again, there may be present some of those injurious com- pounds of iron or salt already described, or an excess of clay or of sand, or too much water, etc. The whole of these cases, a-though of great importance, are mere- ly elementary; for we must remember that in addition to them we require to know how much ammonia, nitric acid, phosphoric acid, potash, and many other elements a soil contains before we can form any just appreciation of its value. Before proceeding to investigate the chemical constituents of a soil, it is, as we have seen, necessary to rigorously examine its physical properties, they being the real basis upon which everything subsequently depends. No man ia his right senses would attempt to build a house on moving sands, and just in the same way it would be futile to seek to introduce chemical elements into a soil, if it were found to be physically incompatible with vegetation and high-class culture. 33 MODERN" HIGH FARMING. To ascertain the true plij^sical and chemical condition of a soil, the following complete investigation must be undertaken : Determination of its density or weight as compared with the weight of water. Determination of its proportions of sand. " " clay. " " " gravel. •' " powers of absorbing water. " " " holding water. " " drying capacity. " " powers of absorbing solar heat. These operations having been satisfactorily performed, and the physical properties thus accurately known, the study of its value for plant alimentation may be proceeded with in the following order : Quantitative determination of its percentage of sulphuric acid . " " nitric acid. " " phosphoric acid. " " nitrogen. " " lime. " " chlorine. " " carbonic acid. " " potash. " " soda. " " peroxide of iron. " " alumina. " " oxide of manganese " " magnesia. " " soluble silicates. Aniifid with the results of this exhaustive investigation, we can At once find out how the soil may with rapiditj^ and economy be brought to attain the highest degree of fertility. CHAPTER VII. PHYSICALLY PERFECT SOILS STRONG AND LIGHT SOILS HO^V TO AMEND CLAYEY LAND CLAY BURNING TREATMENT OF SANDY SOILS GREEN CROPS AS MANURE REMARKS ON DISINTEGRATION " FAIRY RINGS " THEIR EXIS- TENCE EXPLAINED HOW TO KEEP PACE WITH THE TIMES. The most favorable physical conditions of a fertile soil are found to exist in a nearly equal mixture of sand and clay. When it con- tains less than thirty per cent., or about one-third of sand, it should cease to be classed among those fit for agricultural purposes, and, according to its composition, be turned to account in other directions. The two substances — clay and sand — are destined by nature to play respective parts, which may be thus described : the clay to store up and hold together those substances essential for plant food ; the sand to serve as a ventilator or conductor of air and water. As the defects of physically well-constituted lands may be easily discovered and dealt with by chemical analysis, our present pur- pose will be served if we devote our attention to tliose of a less happy nature, which, for convenience, we shall distinguish as strong or clayey, and light or sandy soils ; the former being heavy, tena- cious, plastic, and retentive of moisture ; the latter porous and incapable of holding water. It not uufrequently happens that in some regions both these qualities are alternately met with in consid- erable abundance, extending over very large areas ; and in such cases a judicious mixture is the natural remedy which suggests it- self. In other regions we meet with vast tracts of land wholly 34 MODEEN HIGH FARMING. composed of clay or entirely sandy, and here it is that our ingenuity must be brought to bear. Commencing on a clayey soil with the removal of all excess of water, by a system of surface or substrata drainage, we must look around us for those substances which, by their addition, will com- municate to the clay the necessary degree of porosity. In a previous chapter we have explained that many surface soils have no natural connection with the rocks which underlie them ; that they may have been carried to their present position, and de- posited by water arriving from various distances, and that conse- quently they may cover strata of an entirely different composition to their own. An examination of this point, being very easily made, should never be neglected, because, if beneath the overlying clays we come upon beds of marls, limestones, or sand, we need seek no further for what is necessary to remedy the defects under consider- ation. Presuming, however, the non-existence of any underground source of improvement, recourse must be had to outside means : the application of cinders, furnace refuse, coal dust, or ashes, the ashes of all kinds of burnt vegetable refuse; old and discarded building materials, large quantities of lime, chalk, or marls ; the whole of which will have the desired effect. In some rare cases we have heard it objected that none of the bodies we have enumerated could be obtained in sufficient quantities, near enough at hand to admit of their employment ; and that their transport from long distances is rendered impossible by the heavy and prohibitive charges for freight. Although such objections must soon disappear before the rapid growth of cheaper communications, we cannot afford to overlook them, but, bearing in mind that "labor omnia vincit" must seek and find in the clay itself a solution to the difficulty. First roughly shaped into balls or bricks and allowed to dry in the sun, it should be burnt in small piles made up of alternate layers of clay, wood, coal dust, or any other cheap and readily avail- able combustible material. When the burning process, which gen- erally lasts some days, is terminated, the bricks or balls must be MODERN HIGH FARMIKG. 35 broken up as finely as possible, and, together with the ashes of the combustibles, plowed in a wholesale manner — deeply and thorough- ly—into the field. Our object in burning the clay is to make it undergo a radical chemical transformation, in the course of which it loses its water of combination and its power of absorbing and retaining moisture. If, on the one hand, an excess of clay renders our agricultural operations so arduous, we find on the other that an excess of sand in the soil, and a consequent lack of clay, makes them impossible. The most effectual method, therefore, of dealing with a sandy soil is to add to it a suflicient quantity of clay to hold together the fertilizing and nourishing agents, whether naturally present or arti- ficially introduced ; for unless this is done, all the manurial elements (having nothing to retain them) will be washed from the soil by the rains and completely lost. Where clays are not readily forthcoming, the use of marls and lime must be resorted to with an unsparing hand ; the latter accom- panied with as much as possible of the green refuse — leaves, stalks, etc., etc,, from the various crops. It may even in special cases, and for a certain period, be advisa- ble to use up all the lower orders of green crops entirely as manures for this kind of soil, in preference to keeping or selling them for food ; more advantage being likely to accrue from the beneficial ac- tion exercised by their decomposition than is represented by any mo- mentary profit arising from their sale or consumption. These vegetable substances should be very evenly distributed over the surface of the fields and plowed in simultaneously with the lime. Their beneficial effects arise not only from their power of retention, but also from their attracting and fixing the nitrogen in the air and the soil by the processes already described. In considering all that has been written in the preceding pages upon the combinations and transformations that go on in the soils — their physical and chemical defects, and the means by which we are to remedy them ; and in examining that important question of ma- nures which we are now about to open, there is one essential element 36 MODEEN HIGH FARMING. in the conditions of success la higli farming wliicli we shall do well never to lose sight of. We refer to the necessity of maintaining the land in a fine workable condition by continually and thoroughly dis- integrating, aerating, pulverizing and turning it over. We have lengthily dwelt upon the oxidation and combustion of t he organic matters, and the beneficial action of lime and other ele- ments connected with their decomposition. We have shown how clayey soils may be made porous, and suggested means of rendering more tenacious and retentive those composed of sand. But in all these cases, unless the necessary means are adapted for breaking up the atoms and so finely dividing them as to make them accessible to the action of air and water — in other words, pulverizing the soil — what we have written would be deprived of more than half its value. Now it stands to reason that certain portions of a good soil, and those most valuable because of their tenacity, will by the action of the rainfall become clodded; while others — the sandy and least retentive portions only — will remain in a state of separation or division. If, under such conditions as these, we introduce into the soil a. costly manure containing either nitrates or ammoniacal salts, we shall find that those lumpy, hard and clodded portions, whose express mission it is to keep together and hold these elements in store at the disposal of the tender young rootlets, will not even receive them, and that with the very first application of water they will be washed away. We have all seen — we see every day if we keep our eyes open — not only in our own fields, but in the fields of our neighbors, cer- tain small delightful patches of a luxuriant vegetation, scattered here and there without any regard to order or regularity. The stalks are higher and stronger ; the ears fuller ; the grains larger and more plentiful ; and the whole aspect of these " fairy rings" offer such a marked contrast to the other portion of the surrounding crop, as to irresistibly chain our attention and excite our wonder. But no great genius is needed to discern the cause of this mar- velous effect, which is simply a practical demonstration of two important facts : MODEKN HIGH FARMING. 37 FiKST. — The undoubted efficacy of artificial manures, when well selected aud judiciously applied. Second. — That a badly worked soil, in a lumpy aud imperfect state of division, is incapable of affording to the plants that amount of nourishment essential to perfect development. "Whenever we find it practicable, we recommend deep plowing; and, while filled with a becoming reverence for the memory of our grandfathers, we must deprecate the custom of too closely treading in their footprints. They were fain to rest content with the natural but only partial disintegration ensuing from exposure of the up- turned clods to the atmospheric air ; but we, let us remember, live in an age of progress and of rapid communication ; and in agricul- ture, as in all other things, "the race is to the fittest.'' If we would outrun — or even keep pace with — our competi- tors, we must watch and take lessons from the signs of the times, which teach us that we must increase our production and decrease our cost. In other words, we must make the lands produce their very best and largest crops, and in doing so must not only utilize our capital and our labor, but must freely exercise our brains as well. The general practice now prevailing in Europe, of not only well pulverizing the soil after it has been plowed over and allowed to dry, but of repeating the operation at the time of adding to it the manure, and thus blending and mixing the whole, has been produc- tive of the best results. By following this course we shall attain a highly conditioned and sensitive soil, deriving in due season all the benefits of the rains, frosts, thaws, and solar heat; our manurial agents will be equally disseminate'd over an equally divided soil ; and we shall thus not only render them doubly efficacious, but shall effect a large economy in the quantity necessary to be used. CHAPTER VIII. PROGRESS OF THE MANURE TRADE IN THE UNITED STATES LOW PRICE versus real value how the farmer is SWINDLED BOGUS MANURES NECESSITY FOR ANALYSIS DEMON- STRATED HOW TO STAMP OUT THE EVIL ADVICE TO MANUFACTURERS. To the questions : How are we to prevent the soils from becom- ing exhausted ? — What must we do to increase rather than allow to diminish our yearly production ? we have already foreshadowed our reply. Let us liberally return to the lands the equivalent of that which we have borrowed, and remember that our endeavors to get something out of nothing, will be like trying to squeeze a quart of liquid into a pint pot — sheer waste of time and ingenuity. We have only to look about us to find out that the truth of our doctrine is already admitted ; that it is rapidly gaining ground ; that throughout the length and breadth of this vast country, earnest men are striving by experiment and example to root out existing prejudices. These missionaries are succeeding in their work, surely if slowly. We have the evidence of their success in the steady growth of the principal industries connected with the manufacture of fertilizers, of which the present annual production exceeds 500,000 tons ! What we have now chiefly to examine, therefore, is not so much the necessity of using manures — since that is admitted — as what kind of manures we are to use. When a sensible man purchases a pair of boots, he tells his shoe- maker he wants an article that will wear well, and that he is ready MODERN HIGH FARMIN"G. 39 to pay a fair price for it. Sound quality is liis first consideration. Wliy sliould not tlie very same idea predominate wlien we are buying a manure, and what is tlie invariable consequence of a contrary policy ? In nine cases out of ten the ' ' fertilizer " is but an abomin- able satire upon the name, and, having no other recommendation than its cheapness, produces no fertility. Its purchase is conse- quently the cause of a double loss : first, the money paid for its purchase, and second, the increase which would have accrued from the use of a good manure. As a means of illustrating our meaning, we may here quote a case selected from hundreds which have come under our notice. About three years ago, we were requested by a farmer in the south of France, to explain how we reconciled our theories with the facts resulting from his practical experience ? He had made liberal and costly application of manures to his soils, and no increase or amelioration had taken place in his crops ! Interrogated as to what manure Le had been using, and what was the nature of his soil, he was totally unable to give any satisfactory reply ; but informed us that he had purchased the material, prescribed and recommended by an agent who had called upon him, and that in doing so he had fol- lowed the example of many of his neighbors. Upon examination of his soil, we found it to be of the poorest sandy character, composed as follows : Moisture 1.80 Organic Matter 4.93 Oxides of Iron and Alumina 6.73 Phosphoric Acid traces. Carbonate of Lime 3.01 Potash 0.23 Magnesia 1.49 Sand and Insoluble Silicates 81.82 100.00 Had we been consulted previous to the addition of any manure, we should have recommended, for growing cereals in such a soil as 40 MODEElSr HIGH FARMUSTG. this, a good mixture of about equal parts of cheap cotton-seed cake dust and well made superphosphate, containing about 14 per cent, of soluble phosphoric acid — with the addition of, say, one-fifth of their combined weight of muriate of potash. This mixture, well plowed in and thoroughly mixed, with a heavy top-dressing of slaked lime in fine powder, would not have failed to produce excellent results — considering the poverty of the ground. An analysis of the manure actually used showed it to chiefly con- sist of valueless alkaline salts, sand, and earthy matters (probably a mixture of common poudrette and sand), minute quantities of nitro- gen, and about ten per cent, of phosphate of lime ; the whole with a very fcelid odor, to mislead the farmer, who has somehow an idea that no manure is manure unless it has a strong and characteristic smell. This worthless mixture, foisted upon an ignorant man by a smooth- tongued rascal, was sold to him as phospho-guano, at the price of thirty dollars per ton, in lags delivered at his farm, and would have been dear at one-sixth of that price ! If agriculture is to remain the basis of the wealth of this coun- try ; if the United States are to ultimately become the greatest food producers for the world's teeming millions, there must be no such thing as exhaustion of the soil, or poverty in the crops. The preventive remedies are known to us, and it rests entirely with ourselves to acquire them with certainty. On the one hand we know that an acre of fertile land should contain a certain per- centage of phosphoric acid. On the other hand we have discovered that our own soil falls considerably short of the quantity required by the crops we desire to grow. We base our estimates upon the deficiency, and introduce a given quantity of superphosphate of lime. The law says that, every trader in manures shall guarantee the genuineness of his wares by the. test of chemical analysis. In other words, if superphosphate be sold as containing 13 per cent, of phosphoric acid, and be found to contain only half that quantity, the seller is deemed guilty of fraud and is liable to punishmenl, But MODEEN HIGH FARMIN^G. 41 can any penalty be proportionate to the enormous evil caused by this fraud, by -which the farmer is robbed not only of his money, but of his time, his labor, his seed, the interest on his capital, and the rent of his unproductive land. We are taught by an old adage that, " the wise rogue is the fool's natural parasite," and every day brings fresh instances of the folly and gullibility of mankind. Now, we do not agree with Carlyle in thinking that the majority of our rural population is composed of "mostly fools." and our system of education is gradually raising the standard of their intellect and intelligence, to a point which will soon leave the villages "very little or nothing to learn from the towns. Notwithstanding this, it is unreasonable to suppose that any class of men can suddenly overcome their old habits; discard their tradi- tions ; abandon as worthless all those methods which have been handed down to them through countless generations ; and throw themselves into our arms without due reflection and perhaps some fighting. All great reforms have commenced with small minorities, and have had to struggle in the cause of truth, against prejudice, interest, and established custom, before being universally adopted. Is it not natural to expect that the great discoveries of scientific culture, should at first be sneered at and scouted by those who are unable as yet to understand them ? If the farmer will only take seriously to heart what we are trying to impress upon him ; if he will only realize, once and forever, that the science of high farming is no longer a shadow but a living and indispensable reality, there will soon be an end to unproductive lands. The States have placed at his disposal, and near to his hand, most excellent chemists, ever ready to advise and to assist him ; he can therefore no longer plead ignorance in extenuation of any of his shortcomings. A very trifling outlay, insignificant when compared with the im- portance of the result, will obtain for him all the information he requires : the composition of his soil, the elements in which it is deficient, and in what form those substances can best be introduced. 42 MODERN HIGH FARMING. When these points have all been settled, and when he has pur- chased his manure, chemistry will again step in and determine whether, in Avhat he has bought, the necessary elements are actually contained. We are all inclined, more or less, to be negligent even of our best interests, and we are satisfied that the majority of our farmers do not trouble to analyze the manures they purchase, but are fain to rely upon the promises and representations of the dealers. Alas ! for the frailty of human nature ! " Opportunity makes the thief." How many fertilizer mixers and dealers, arc there in the world who are too high-souled to profit by this situation ? If once the custom of analyzing all purchased manures becomes a thing of course — looked upon as part and parcel of the commercial transaction ; if once our farmers will take the trouble to ascertain the monetary value of all the ingredients employed in making man- ure, they will be able to distinguish what is good from what is worthless, and by ceasing to buy cheap "rubbish," will deal a death- blow at those miserable swindlers who trade in stuff which is "only made to sell." The foregoing remarks are prompted by our strong desire to sup- press an evil, the dire effects of which are so widespread as to in- directly strike at every interest. If we are to have cheap food it must be produced in abundance ! How can it be produced in abundance if agriculturists are baulked in their efforts at improvement, and ruined by their purchase of ma- terials which can give them no return ? The extensive sale of these so-called fertilizers under high-flown names, has done much to disgust those who have been victimized, with all ideas of progress, and has inspired them with such distrust of artificial manures, that, rather than make fresh trials and run fresh risks, they prefer to see their lands in a stale of comparative sterility. There surely must be — there naturally is — a large number of manure manufacturers in the United States of strict integrity and undoubted honor, and we would suggest to these, that they have a MODERN HIGH FAEMIKG. 43 remedy against this evil iu their own hands, which, better than any legislative measures, can at once stamp it out. Let first-class manufacturers be of less difiicult aiDproach to the real consumers of their produce, and let them at once pass over the " middlemen " Avho find in adulteration such ready means of making profit. Let them now organize, in every region within reasonable access of their works, some kind of farmers' commercial club or "fertilizer syndicate" (?) with an energetic president and capable secretary. Let it be the duty of these two officials to discover and to tabulate the actual requirements of every member, in all kinds of manures, so that at proper seasons and in convenient time they may be manufactured in one batch. Let some good chemist be chosen by the club on the one side and by the manufacturer on the other, and arrangements be made for contradictory sampling. Let the deliveries all be made at the same period, and allow the sampling to be performed in the presence of a chosen representative of the club, when the manure has been loaded and is ready for delivery. Let analyses of each parcel be made by the respective chemists, and in case of a sensible dilTerence between them, by a third chemist m.utually agreed upon and whose decision would be final. Let each member furnish to the club in some form agreed upon at a general meeting of their whole body, a suitable guarantee for the due payment pro rata, of the portion of manure supplied and invoiced to him by the club. Finally, let the club itself arrange with its local banker, by a transfer of the securities which it has received, to guarantee the pay- ment of the manufacturers' invoices in due season, say at four or six months, from the date of delivery. The advantages of some such a system as this, appear to us to be very striking, and we feel certain that its adoption would be pro- ductive of mutual benefit and general satisfaction. CHAPTER IX. THE DIPPEKENT KINDS OP MANUKE NOTES ON VEGETABLE JIA- NUKES ANIMAL PRODUCTS THEIR ANlSTtJAL RECKLESS WASTE ESTIMxiTE OP THE LOSS TO AGRICtJLTtl RE HINTS ON THEIR PRESERVATION AND UTILIZATION GUANOS DESCRIBED AND ANALYZED THEIR VARIABLE QUALITY FISH MANURES TABLE OP NITROGENOUS SUBSTANCES. A complete description and analysis of all the substances used as manure would of itself fill a considerable volume, but we doubt wlietber the advantage of sucb a treatise would be proportionate to the labor of its compilation. We shall therefore confine our remarks to those of generally recog- nized utility, classing them as vegetable, animal, mixed (or farm- yard), and mineral manures. Vegetable Manure. Every description of plant — roots, stalks, leaves and seeds — becomes, when plowed into the soil, a valuable fertilizing agent. The most important, however, are those of the leguminous species, thanks to their long and trailing roots, by means of which they pen- etrate to a considerable depth into the earth, and thus acquire from below, elements which other jilants are unable to attain. From this reason the benefit of rotatory crops becomes manifest, and we understand at once why wheat crops are so much more plentiful, when following two or three crops of clover or luzerne. The quantity of roots and stubble, or waste, from a crop of clover has been estimated to weigh, when dried at a normal temjoerature, one thousand pounds per acre. This would contain about fifteen MODERN HIGH FARMING. 45 pounds of assimilable uitrogen, and consequently be equal to nearly two tons of ordinary farm-yard manure. Oil Cakes contain five per cent, of nitrogen and about three per cent, of phosphoric acid, with traces of potash. When damaged or otherwise unfit for cattle-feeding, they may be employed as ma. nures with excellent results, especially on sandy or too porous soils. In some districts near the coast, the sea weeds gathered along the shore are found to have a beneficial action, but as they contain a maximum of one per cent, of uitrogen and insignificant portions of phosphoric acid, we must consider their efiiciency to solely arise from their slow carbonization or decomposition. "We have already dwelt at considerable length, in ^ur previous chapters, upon the chemical action of vegetable organic matter on the various bodies contained in the soil, and it is only necessary to repeat here that in all cases where it is desired to grow cereals and to pro- duce plentiful crops on an economical basis, the farmer will do well, rather than sell his green crops, to plow them into his wheat field as manures, and to plow them in evenly and with an unsparing hand. Animal Mantires. Those within this category most worthy of attention are human dejections, guano, blood, fish, wool, rags, horns, hoofs, hair, and all animal refuse from the slaughter houses. The efficacy of night-soil as a fertilizer has been recognized from time immemorial by practical farmers, but it is still more so now that the advancement of science has permitted us to accurately esti- mate its valuable elements, and to judge of the reckless manner in which they are yearly thrown away. If we take the average weight of the entire population in the Uni- ted States at ninety pounds each for men, women and children, we find that the daily product proportionate to this weight must not be less than two pounds per head. The present population being estimated at fifty-five millions, we should reach the figure of fifty-five thousand tons jjer day, or, in round figures, twenty million tons per year. 46 MODERN HIGH FARMING. Taking the active principles to be in the proportion of 27 pounds of nitrogen and 6 pounds of pliosphoric acid per ton, we can easily arrive at the annual total value by the following simple calculation : 27 + 23,000,000= 270,000 tons nitrogen, at $50 per ton, $13,500,000 6 + 20,000,000= 60,000 " phosphoric acid, $30 " 1,800,000 Net total value, $15,300,000 It is a standing reproach to chemical science that we have not been able to devise a means of practically turning these vast agricul- tural necessities to account, and that because of our inability to con- veniently store and render them inoffensive, our legislators are com- pelled to send them through the sewers into the sea. All the attempts hitherto made to recover these substances from the sewage by means of precipitation have ended in failure, from the fact that chemistry has not yet discovered a method of effecting this precipitation, owing to the extreme solubility and volatility of the efficient constituents. If these elements of fertilization are ever to be turned to good account in tlie proper channels for their employment, they must be kept out of the sewers, where they do immense harm by contamina- ting our drinking water and propagating diphtheria, and be sub- mitted to some practical process of rapid desiccation. The system by which these materials are turned to account in some parts of Europe, consists in allowing them to deposit in tanks, built for the purpose. In due course the supernatent liquid is decanted off and used for the manufacture of sulphate of ammonia ; while the solid portion is dried up by the addition of slaked lime, and sold in bags under the familiar name of powdlreWe. A good sample of this manure, lately submitted to us for analysis, was found to contain forty-eight per cent, of organic matter, two and one-fourth per cent, of nitrogen, six per cent, of phosphoric acid and ten per cent of lime ; and would doubtless be productive of very excellent results in the field. Wherever such operations are practicable, we strongly recom- mend all farmers to build small tanks in various portions of their MODERN HIGH FARMING. 47 ground. These tanks should be about five feet square and six or seven feet in depth, and must be carefully lined with good Portland cement. Into these tanks should be thrown the whole of the night soil collected in the neighborhood ; care being taken to keep them well covered by nicely adapted wooden lids, and to exclude the entry of water. The occasional addition of finely powdered slaked lime will assist the drying and effectually destroy all smell. Guano. No name is more widely and generally known, even to the smal- lest child, than that of this popular fertilizer, and although it has served for many years as a cloak to swindlers of every kind, who have sold under its name piles of worthless trash, farmers can- not forget their old affection for it. There can be no doubt that, for a considerable length of time after its introduction, very marvelous effects followed the applica- cation of this manure, but the enormous and continual drain upon the production, and the never- varying result of speculation and job- bery, would seem to have told a tale upon it, and the quality is now of a very variable nature, with a tendency to become more and more so, as time goes on. The principal sources of supply are Peru, Chili, Bolivia and the South Sea Islands ; and the deposits proceed from a species of sea fowl known as Guanaes, which feed upon the small fish that liter- ally swarm the waters near the coast. The high percentage of nitrogen contained in the Peruvian ship- ments of former years, must be attributed to the absence of rain, which characterizes that country; those arriving from other regions having lost a considerable portion of their ammoniacal salts through the action of water. The trade in Peruvian guano is monopolized by the Peruvian government, and the immense deposits sometimes attain a depth of one hundred feet. This latter fact has induced a great deal of controversy as to the period from which we should date their commencement, some author- 48 MODERN HIGH FAEMING. ities being of opinion tliat it must necessarily be before the deluge. In his very able book upon tlie subject, Mr. F. de Rivero ad- vances some skilful arguments to prove that they are of more recent date ; and, basing his calculations upon the existing quantity of about 20,000,000 tons, he says : "Presuming the constant presence of only 264,000 of these birds, (and I am perfectly convinced there is nothing at all exaggerated in these figures), supposing each bird to furnish but one ounce of ma- nure in every twenty-four hours, we easily arrive at the figure named, in a period of between five and six tliousand years." - . The value of real guanos from all sources is estimated upon tlie basis of their nitrogen, ammonia, phosphate and organic matter, and when of sound quality they have generally realized from. $65 to |70 per ton. Tlie following are the analyses of two cargoes purporting to be of the same quality and shipped from the same port at tlie same time, arriving in London at the commencement of 1882 •• Peruvlvn Guano. Cakgo Ko. 1. Moisture 10.00 / .53.50 *Orgaiiic Mal.tcr, Salts of Amiuoiiia Phosphate of Limo 19.53 tPhosphoric Acid 3.13 Alkaline Salts 8.00 Insoluble and Sandy Matters 0.8G 100.00 ♦Nitrogen 1 5 30 tSoluble Phosphate of Lime 6.76 Cargo No. 2. . . 15.38 ..14.72 ..33.13 . traces .. 8.93 ..27.95 100.00 .. 3.70 ..none As tliese are far from being exceptional instances of the great uncertainly of tliese products, we feel compelled — while admitting that no better manure than good guano is to be found — to advise the discontinuance of tlieir use, and the employment of well-made chemical substitutes, until shippers guarantee them to contain a stii3ulated minimum percentage of the active principles. MODERN HIGn FARMING. 49 FiSlT. The refuse of all kinds of fish afford sources of the richest and most desirable liind of manure, and it is unfortunate that some wholesale and cheap method of popularizing it has not been fortli- coming. When cooked, deprived of its oil and water by heavy pressure, and thoroughly dried, it is easily reduced to a fine powder, of which the following is an average analysis : Moisture 1.30 ♦Nitrogenous Organic Jlatter 78.01 Alkaline Salts 5.30 Chloride of Sodium Traces. Phosphate of Lime 15.00 Magnesia 0.33 Carbonate of Lime Traces lusoluable Siliceous Matter 0.06 100.00 *Equal to Nitrogen 10.00 Blood, Wool-Refuse, Hair, Hoofs, Horrs and Offal. — All these are valuable sources of nitrogen, and in some cases may be economically and beneficially employed. They call for no special mention and are nearly all old friends of the agricul- turist. We append a list of sundry materials showing their ap- proximate percentage in assimilable nitrogen, which may not be without utility. Table showing the quantity of nitrogen, in pounds, contained in evert) one hundred pounds of the following substances : Nitrogen. 100 pounds of Shoddy contain 7Vij lbs. 100 " Wool Du-t contain 03^ lbs. 100 " Dried Blood contain 12 lbs. 100 " Rape Cake contain 5 lbs. 100 " Cotton Cake contain 53^ lbs. 100 " Sugar Scum contain _ 3 lbs. 100 " Glue Refuse contain 2]/, lbs. 100 " Leather Cuttings contain 8 lbs. 100 " Crude Ammonia contain TJ^ lbs. CHAPTER X. FARM- YARD MANURES COMPOSITION OF THEIR LIQUID AND SOLID ELEMENTS COMPARATIVE VALUE OP ABSORBENTS, "WITH ANALYSES COMPOSITION OF VARIOUS STRAWS SUPERIOR VALUE OF THE LIQUID SUBSTANCE HOW TO PRESERVE AND UTILIZE IT TREATMENT OF MANURE HEAPS HOW TO COMPLETE THEIR VALUE AS FERTILIZERS THEIR DE- COMPOSITION FORMATION AND DESCRIPTION OF HUMUS EXPERIMENTS ON FRESHLY MADE AND FERMENTED MA- NURES RESULTS OF EACH EXPERIMENT GENERAL RE- MARKS. In entering upon an examination of what is perliaps the most im- portant matter with whicli we have had to deal, we shall carefully avoid all ideas of prejudice and partiality. None of us ignore that farm yard manures have for many cen- turies been the prop and mainstay of our agricultural operations, and no science was necessary to teach us that it owed its virtues to its happy combination of physical and chemical constituents. If it were possible for those who cultivate old or mature soils to manufacture a sufficiency of this manure, the introduction of chem- ical substitutes would in their case be unnecessary, and the problem which is occupying our attention would never have arisen. The requisite quantity to constitute complete restitution could, however, be only attained by literally putting back the whole of the crops and living things which have derived direct and indirect sus- tenance from the soil; and hence, even if such an idea were not ab- surd, it would be impracticable, since the grains, seeds, cattle, poultry, milk, butter and wool, are all sent to market and go to feed the teem- ing populations of the towns. MODERN HIGH FARMING. 51 Such manures as we are able to gather up in and about our farms, from all sources, may consequently be considered as the mere excess taken from the soil by the crops gathered in, and would certainly not suffice of themselves to stay the already marked impoverishment and eventual exhaustion which must naturally be the effect of such a comprehensible cause. We may, therefore, consider the employment of chemical and artifi- cial fertilizing matters, as not one whit less necessary in places where an abundance of offal appears to exist, than it is in other circumstan- ces where there is very little or none at all, and the liberal employ- ment, judicious selection and economical purchase or manufacture of sound manurial materials is the fundamental condition of suc- cessful high farming. We must consider it a matter of very third rate, if of any impor- tance to us, whether a manure is vegetable, animal, mineral, natural or artificial, having merely to assure ourselves by chemical analysis that it contains the needful elements, and that by its emploj'ment we can increase our crops and enhance our profits. The value of stable dung must not be estimated upon its actual richness in ammonia or phosphoric acid within a short period of its production, but must be calculated on its wonderful physical and chemical action on the elements of the soil and the air, and upon its merits as a vehicle or conductor into which completing quantities of outside substances can be introduced, decomposed, and rapidly made available. The composition of its different constituents may here be set forth in the. following order : Analysis of various ki7ids of Stable Urine. Sheep Horses Oxen Goats Pigs Water 06.40 90.50 91.40 98.30 98.20 ♦Organic Matters 1.00 5.50 5.50 0.90 0.50 tAlkaline Salts 2.60 4.00 3.10 0.90 1.30 100.00 100.00 100.00 100.00 100.00 *Coutainiiig Nitrogen 1.70 1.75 1.50 traces minute quan. t " Phosplioric Acid. . .traces traces traces traces traces 52 MODERN HIGH FARMING. The quantity per head yearly produced of this liquid may be estimated at : For Cows Four to Five Tons . " Horses Three to Four Tons . Analysis of various Jcinds of Solid Excreta. Sheep Water 68.71 • ^Organic Matters 23.10 tAlkaline Salts 8.13 100.00 lOKSES Oxen Pigs 78.30 79.72 75.00 10.10 10.04 20.15 2.54 4.24 100.00 4.85 100.00 100.00 0..55 0.32 70 1.22 0.74 «.87 ♦Containing Kitrogen 0.72 t " Phosphoric Acid 1.52 The result of many investigations of the mixed matters ahovc detailed, prove them to contain in eveiy hundred pounds rather Icfs than half a pound of nitrogen and about two pounds of phosphoric acid. The collection, absorption, and association of the liquid with the solid matters, being the most important factor in the manufacture of an efllcicnt product, it is in all cases advisable to use abundant quantities of cereal straws for littering or bedding, in preference to any other material; thej' having been found to possess the greatest possible capacity for holding moisture, as indicated by the following figures : Table slioioing the powers of ahsorhing water in 2Ji hours, hy every 100 pounds of the follmcing kinds of straws, as compared xoith those of other su'jstances. Wheat Straw absorhs 110 pounds. Barley Oats Colza Corn .285 " 200 " 102 Marl absorbs 40 Dry vegetable soil absorbs, 50 The chief active principles which form the composition of cereal straws and other vegetable matter, commonly used for bedding in PiiosnioKic Acid Nitrogen 0.25 0.24 0.15 0.17 o.co 0.23 0.21 0.28 0.8G 0.19 0.36 0.75 0.28 0.10 0.22 0.20 0.59 1.79 MODERIf HIGH FARMIKO. 53 stables, have been ascertained to be the following : the quantities shown in the table being those contained in every ICO pounds, by weight of the substance analyzed. Ashes Wbeat Straw 3.51 Rye " 2.79 Barley " 5.24 • Oats " 5.75 Corn " 4.00 Colza Tops 3.85 Velchc " 5.10 Bean " 3.10 Pea " 5.00 We have very frequently observed that in the minds of some farmers — producers of large quantities of stable offal — the pre- vailing idea is, that the solid portions are those really valuable, and that the liquid may be neglected and abandoned. Our great object in giving the above analyses, is to impress upon such men as these the utter fallacy of their opinions, and the necessity for their im- mediate reform, and to persuade them that they are continually making serious losses by the w^aste of this precious fertilizer. We suggest the adoption of a good system of drainage in every stable, the flooring of which should be upon a slight incline to allow the liquid to pass off with facility, by means of underground pipes made if possible from good refractory clay. The urine should be con- ducted to tanks or reservoirs, of a similar nature to those already recommended in a previous chapter, and be kept well covered over; these tanks should be connected with a pump, by means of which the liquid could frequently be made to saturate the forming heaps of manure, thereby serving to steady and regulate the fermentation or process of combustion going on within. If due weight is attached to those points, they will produce the double advantage of increasing the quantity of ammonia contained in the ultimate manure, and of decreasing the risk of contaminating the wells or springs made use of bj' the cattle, if not by the popula- tion of the neighborhood. 54 MODERN" HIGH FARMIISTG. The solid portions and tlie saturated straw sliould be allowed to remain under the cattle as long as is consistent with health and con- venience. And when forked up should he carefully mixed and deposited m uniform layers upon the heap ; care being taken to break up and disseminate all lumpy portions, before the application of the liquid by means of the pumping process above described. The very highest possible results will be obtained if, from the com- mencement of each heap, thehabit is contracted of regularly adding to each layer, as it is put on, a certain evenly distributed quantity of some artificial manure, the nature of which will be dictated, and vary, according to the wants of the soil and contemplated crops. Supposing a high grade phosphatic material combined with potash to be necessary, nothing could be better than the addition of a good, soluble, ten or twelve per cent, superphosphate of lime, and muriate of potash, in the proportion of twenty-five pounds of the first and ten pounds of the second, to every hundred pounds of manure. Whereas, if nitrogen is the element required to pre- ponderate, the introduction into the compost of wool refuse, leather scraps, glue refuse, blood and other offal, collected from the various dealers, manufacturers and slaughter-houses, in the nearest towns is highly recommended. The chemical transformations or reactions which go on in the compost heaps during their fermentation, are of too complex a na- ture to be fully described within the limits we have prescribed for ourselves, nor is its precise knowledge of any necessity for practi cal purposes. We shall therefore rest content with explaining that a process of slow combustion or carbonization very soon sets in, and serves to maintain a temperature of about 100° to 105° Fahrenheit. The air within the mass being composed of carbonic acid and nitrogen gases, with traces only of oxygen. By making a clean incision in such a fermenting manure heap as we have described, through the centre from the top to the bottom, we shall find that while the straw at the surface maintains its normal appearance, it gradually assumes a dark brown color towards MODERIsr HIGH FARMIJSTG. 55 tlie middle and is altogetlier lost lower down, in a black slimy mass of decomposition called humus. This body is formed under the influence of atmospheric oxygen by the union of certain elements contained in the straw or vegetable matters, with the ammonia emanating from the fermenting animal matters urea, uric acid, etc. Tliat the presence and intervention of these vegetable elements is indispenable to the preservation or fixation of ■ the generating nitrogen, is demonstrated by the fact that, if the animal matters were left to ferment by themselves; this element would rapidly change into the phosphate, thence into the benzoate, and finally into the carbonate of ammonia, in which form it would immediately vol- atilize and be a total loss. Humus therefore not only changes this volatile carbonate into a fixed and staple product, but possesses the faculty of absorbing and retaining fresh nitrogen from the air and rendering it assimilable when transferred to the soil. We hope that by these explanations we have impressed upon farmers the necessity of allowing their farm yard manures to undergo a thorough process of fermentation, and to completely rot or carbonize before making use of them in the field, and in order to make our meaning still more cleai', let it be remembered that : A. — If freshly made manure be put into the soil, the saline and nitrogenous portions will all be washed away by the first fall of rain, and lost. B. — If the manure be allowed to thoroughly ferment, the nitro- genous matters will remain insoluble in the soil, and will thus be held at the disposal of the plants ready for assimilation. A series of very interesting experiments upon the laws laid down by the illustrious Paul Thenard, were recently made by ourselves, in verification of these assertions, with the following results : The drainings from a field near Leeds, in Yorkshire, liberally dressed with freshly made manure, were submitted to careful analysis after a heavy shower of rain, and found to contain note- worthy quantities of nitrogenous matters. 50 MODERlSr HIGH FARMING. After publishing the complete results of these experiments, ■v\'e ■sverc enabled to collect the drainage from a large field in Ports- mouth, Hampshire, which had been thorouglj" dressed with com- pletely fermented manure, and in this case the water was found to bear mere traces of ammonia or nitrogenous substances. A few experimentors have striven within the past few j'cars to persuade themselves and the world that the total abandonment of farm yard manure, and the sole employment of chemical fertilizers, woiild result in immense economy and increased production; but in nearly every case within our knowledge, where the seduction of these theories has prevailed over common sense, the result has been, to say the least, discouraging. That artificial manures of every kind are necessary, we have alwaj'S admitted and shall alwa3's propound ; that as supplements in all cases, and substitutes in some, their constant employment is naturally indicated, we readily agree ; but that they can ever profit- ably and iisefully replace those made on the farm either physically or chemically, is a proposition, to our minds, too ridiculous to merit discussion. When due care has not been taken in their preparation and treatment, their actual and normal percentage of ammonia may be slight, and their rahie, from that standpoint, insignificant ; but even then, (and we are taking them at their worst), if their fermen- tation has been complete, and their rapid oxidation assured by thorough plowing in and frequent turning over in a well-conditioned soil, no artificial nitrogenous fertilizer can ever be compared to them for economy and proportionate cflicacity. CHAPTER XI. MINERAL MANURES BONES AND WHAT THEY TAUGHT US SULPHURIC ACID AND NITRATE OP SODA BONE ASH ANIMAL CHARCOAL, OR BONE BLACK BONE MEAL SULPHATE OF AMMONIA ITS GREAT POWER OP DECOM- POSING OTHER MANURES HOW TO DETECT IMPURE NITRATE OF SODA NITRATE OF POTASH, OR SALTPETRE PHOS- PHATE OP LIME RIVER PHOSPHATES CANADIAN PHOS- PHATE A RIDICULOUS EXTORTION. ^Vc liiivc now to undertake the examination of those mineral fertilizers which come next in order, and which form the staples of that great and advancing industry, chemical manure manufac- ture. For the sake of comprehensiveness and brevitj^ we propose to divide our subject in the following order : First. — A hasty glance at the principal sources and the agricul- tural value of phosphatic and other raw materials of a min- eral nature, with analytical tables showing their composition. Second. — A description of the principal sources of sulphur pyrites, and of sulphuric acid and superphosphate manufacture, with brief notes on the mixing of various compound manures. As we have already roughl^^ described, in a preceding chapter, how mineral phosphates are found in nature, we need merely refer oiu' readers to the particulars there given, and at ouce attack the practical question before us. Bones are a very old and very favorite manure, and it is to then- emploj'ment and to the researches ensuing upon their marked effect that Ave owe our discoveries relating to tlie part played by plios- phoric acid in the soil. 53 MODERN" HIGH FARMING. Their extensive use in tlie mamif acture of phosphorus has, how- ever, so much enhanced their commercial value, that we may look upon them as beyond the reach of the agriculturist. When dissolved in sulphuric acid and mixed with nitrogenous materials, or farm-yard offal, to form complete manures, they may be considered, as occupying the very foremost place in the order of merit as fertilizing agents. They are frequently used with nitrate of soda, in the raw crushed state, as a dressing to sandy soils and pasture lands ; but we have personally found their action in these cases to be very slow, and their assimilation a work of time, so that we cannot recommend a continuance of the practice. Bone Ash results from the burning of bones and is chiefly ex- ported from the cattle-raising districts of South America, where, fuel being scarce, the bones are burnt in the process of extracting the fat from the slaughtered oxen. Animal Charcoal ok Bone Black is justly esteemed by all those who are fortunate enough to obtain it on reasonable terms. It is an excellent absorbent, and is extensively used in sugar refin- eries, Jjeing only delivered to agriculture when it has lost its powers of discoloring the juices. Bone Meal is the impalpable powder of bones, from which a steam process has succeeded in extracting all the gelatine. The following table shows the general composition of these ma- terials : Crushed Bone Bone Bones. Ash. Meal. Moisture C.94 2.1S 5.37 ♦Organic Matter 36.93 6.43 17.15 Pliospliate of Lime 48.26 69.95 68.03 Carbonate of Lime and undetermined Mineral Salts.. 7. 40 14.01 9.16 Insoluble Matter 0.41 7.43 0.40 100.00 100.00 100.00 ♦Containing Nitrogen 3.72 Traces. 1.58 SuLPH.VTE OP Ammonia is largely obtained from animal urine, but chiefly from the ammoniacal liquor derived from gas works MODEKN HIGH FAEMING. 59 after the purification of gas. These liquors are mixed with fresh slacked lime and forced to the top of small towers, into which are fitted a series of trays. The liquid flowing over the edges of these trays in a succession of small cataracts, is met and traversed by a column of steam, which during its ascension, deprives it of all its ammonia. The steam thus charged is conducted to a coil of perforated pipes in a tank of sulphuric acid, to which, as it passes through, the ammonia is yielded up. When the acid is fully saturated, it is led into another tank and allowed to settle, and finally is subjected to a process of hot concen- tration to effect the crystallization of the sulphate of ammonia. This salt has the form of white or greyish transparent crystals, is sharp and bitter to the taste, is soluble in twice its weight of cold water, and contains an average of twenty-one per cent, of nitrogen. We have before alluded to it as an invaluable source of nitrogen, and this, although sufficient, is not the only virtue for which it recom- mends itself. Our own experiments induce us to believe that when introduced into the soil, the sulphuric acid set free by its natural transformation, largely assists the decomposition of all surrounding organic remains, and transforms any phosphoric acid that may be present into acid or soluble phosphate. Nitrate of Soda is a natural mineral, principally found in Chili and Peru, and shipped from Iquique. It occurs in large beds, several feet thick, intimately mixed up with sulphate, chloride, iodide of sodium and many other bodies, and when in this state is known in commerce as caliche, or crude nitre, of which the follow- ing is a typical analysis : Nitrate of Sodium 63.92 Sulphate " 4.01 Sulphate of Lime Traces. Sulphate of Magnesia Traces. Chloride of Sodium 28.32 Iodide " V6 Insoluble Matter S.99 100.00 60 MODERN HIGH FARMIXG. After having uudergoue the refiuiug process, it coutaius 95 per cent, of pure nitrate of soda, and 14 to 16 per cent, of nitro- gen, and is then found to be a highly stimulating manure for grass- growing in meadow lauds. In consequence, however, of its very high price, it is frequently, if not generalh', the object of adulteration, and should, therefore, never be purchased from any but respectable firms with a written guarantee of its analytical contents. Even when this is obtained, it should not be employed before its genuineness has been ascertained, and the following rough but sufficiently accurate test can be applied by every farmer, when no chemical laboratory is near at hand. A small portion of the nitrate is to be mixed in a tea cup with sufficient oil of vitriol (sulphuric acid), to just cover it, when, if a copious quantity of greenish, suffocating vapor be given off, it will be evident that the article contains a large proportion of common salt, this being, from the similarity of its appearance, the adulterant generally used. Nitrate of soda plays a very leading part in the manufacture of sulphuric acid, as will be seen later on, being used in the proportion of about 5 per cent, of the weight of sulphur consumed. The fact of its costing from fiftj" to sixty dollars per ton, renders the question of its economical application one of the most difficult with which manufacturers have still to deal : and there are unfortu- nately many works where, owing to unskillful manipulation, instead of five per ce/U., double that quantity more correctly expresses what is used or wasted. Supposing, therefore, that in an acid works which burns ~,000 tons of sulphur per annum, in any of its forms, 10 per cent, of nitrate is consumed, we may fairly consider that there is an unnec- essary waste of 100 tons of nitrate of soda, and this at $50 per ton represents a yearly dead loss of $5,000. There are a great number of our sulphuric acid manufacturers who do not give this matter sufficient attention, and who, consequently can make no real profits ou their acid productions. MODEKX niGK FARMING. 61 Nitrate of Potash, commonly called saltpetre, is industrially produced by the double decomposition, resulting from a mixture of nitrate of soda and muriate of potash, with the application of heat. Commercial saltpetre contains 10 to 12 per cent of nitrogen and from 40 to 44 per cent, of potash. It is soluble in three times its weight of water at an ordinary temperature. MuuiATE OF Potash is, as we have already pointed out, the best form in which to introduce potash, either directly into the soil, or as a constituent iu a compound manure. When freed from its chloride of sodium, sulphate and chloride of magnesia, which always accompany it, the salt contains from 45 to 48 per cent, of pure potash. It is soluble in five times its weight of water, and has a salt and bitter taste. Phosphate of LiiiE. — The most readily accessible materials for consumption in the United States, are the phospliorites of Charles- ton, South Carolina, and the apatites, or crj'stallized phosphates, of Canada. The phosphorites of the Charleston basin occur in the form of nodules, bedded in the clay and sand. They cover an immense area, and are found iu detached deposits, at irregular intervals, all along the water-courses of the country ; through the swamps and on the banks of the rivers and streams. They are generally irregular iu form and color, being partially rounded by the action of water, and of a yellow, green, or brown ; while fussilized remains of fish are always, more or less, intimately mixed up with them. They are distinguished in commerce by the names. Land and Eiver phosphates — the first being the softest and lightest colored. They are dug up and submitted to a washing process, which *"re; s them from nearly all the sand and clay, and when thoroughly uiied after this operation, are ready for grinding, and present the following average composition : ii2 MODERN" HIGH FAKMING. 1 2 3 Moisture 4.89 3.10 7.89 Water of combination 2.01 1.55 1.57 *Phosplio.-ic Acid 25.60 23 33 22.10 Lime. 37.19 30.02 37.18 Magnesia 0.75 0,80 traces. Oxide of Iron and Alumina 9.16 8.70 10.02 Carbonic Acid 4.09 5.00 3.97 Sulpliuric Acid 1.77 2.00 )'^o Cliloride of Sodium 2.03 1.97 [-^§ 5.15 Fluorine and los-s 2.22 2.14 ) a ^ Insoluble and Sandy Matter 10.29 15.39 12.12 100.00 100.00 100.00 *Bqual to Tribasic Phcsphates of Lime 55.80 CO. 85 48.17 The river phosphates are generally of a somewhat higher percent- age than the above, and uow^ furnish the bulk of our supply. They usually contain minute quantities of iron pyrites, are of a dark gray, nearly approaching to black color, and are extremely hard and difficult to reduce to an imijalpable powder. When dried and ready for shipment tlie general average result of their analysis is the following : 1. 2. 3. Moisture 0.63 0.71 0.56 Water of com biiiatiou and loss oa ignition ... 3.09 1.27 2.80 ♦Phosphoric Acid 29.03 27.30 25.33 Lime 45.27 39.22 39.20 Magnesia Traces. 0.35 0.27 Oxide of Iron and Alumina 9.10 9 36 10.15 Carbonic Acid 3.34 3.18 2.70 Sulphuric Acid, j Chlorideof Sodium I By difference 3.42 6.70 4.79 Fluorine, J 6.13 n.cji 14.20 Insoluble Sandy Matters 100.00 100.00 100.00 ♦Equal to Tribasic Phosphate of Lime 63.28 59.50 55.20 Tliey are mined from the rivers under concessions from the gov- ernment, in consideration of certain royalties paid into the State coffers, for every ton extracted and taken away. The deposits are very extensively worked throughout the entire year, but most energy is displayed during the summer months, vfhen they afford employment to thousands of work-people. MODERN HIGH FARMING, 63 The dredging apparatus ordinarily employed is fitted with washers which effect the separation of the phosphate from the sand and other extraneous bodies, while being raised through the water. Both qualities of these phosphates, when finely ground, afford an excellent material for superphosphate manufacture, despite their somewhat heavy percentage in iron and alumina, and their large pro portion of insoluble matter. As they contain very little carbonate of lime, their treatment entails no waste of sulphuric acid, and they possess the superiority over many other phosphates, when properly decomposed, of yield- ing up all their phosphoric acid in a soluble form. Canadian Phosphate occurs in the form of bottle-green crystal- line masses, more or less associated with portions of the gneissic rocks or mica slates which surround it in its native fissures. It is in all respects a mineral, and is found in clearly defined veins and cavities, extending sometimes to a very considerable depth, and be- coming richer in their yield as they go down. The following analyses are fairly representative of its general com- position, and have been selected from many hundreds made by our- selves and differing only in trifling details: 1 2 3 Moisture and Water of combination 0.09 0.13 0.59 ♦Phosphoric Acid 41.13 37.63 35.28 Lime 53.ro 50.95 47.19 CarbonicAcid 1-37 l.CO 1.18 Sulphuric Acid traces 0.26 traces Oxideoflron 0.06 1.12 2.51 Alumina 0.54 0% 3.60 Magnesia traces traces traces Fluorine 2.14 4.07 5 30 Insoluble Siliceous matters 0.97 3.28 4.35 100.00 100.00 100.00 ♦Equal to Tribasic Phosphates of Lime 89. 65 82.05 76.90 ^ When pure it is a fluor-apatite, composed of phosphate of lime and fluoride of calcium, and is generally presented to commerce in the rough, in blocks varying in weight, from one to several hundred pounds, of a beautiful green color and brittle texture. 64 MODERN HIGH FAEMING. It is, however, as the foregoing analyses show, not very frequently met with in a high state of purity, but generally contains certain portions of iron and alumina, besides being mixed up with quanti' ties of an inert kind of gangue, from which its separation (by hand work) is arduous and costly. These phosphates are extremely hard and difficult to grind, and may be said to contain no carbonate of lime. Their percentage of iron and alumina is not sufficiently high to militate against their sat- isfactory decomposition, but what causes them to be regarded with disfavor, is their variable, but always considerable proportion of fluorine, which, upon being brought into contact with sulphuric acid in the manufacturing process, generates large volumes of most irritating and poisonous vapors of hydrofluoric acid. The great inconvenience and danger arising from this cause, can only be obviated by bringing the acid to bear upon the mineral and effecting its decomposition, in well-closed mixers. If these mixers are provided with proper ventilating shafts, to carry off the gases as soon as they are set free, no cause for apprehension will any longer exist, and the material will yield the most satisfactory results, A large majority of manure producei'S in this country have, how- ever, hesitated to make the needful changes in their plant, and have preferred the use of South Carolina phosphates, as offering much less difficulty from an industrial, and yet excellent results from a commercial point of view. In consequence of this policy the greater portion of Canadian apatites have always been, and still are, shipped to England, whence they very frequently come back to America as superphosphates of lime. It is to be devoutly hoped that the rapid progress now being made in all the arts throughout the United States, will shortly induce the larger manufacturers to reconsider their policy and make more use of this excellent and high grade phosphate. Why should American farmers bear the enormous loss represented by the cost of freight from Montreal to English ports, and from thence back again to their own ; amounting in the aggregate on the manufactured article to a total of seven or eight dollars per ton ? MODERlSr iTIGH FARMING. 65 If the use of chemical manures is to become a uaiversal institu- tioa and a " thing of course," they must be placed within reach of consumers, at the lowest possible price ; because, were the main- tenance or increase in the quantity and quality of our crops to be simply counterbalanced by the cost of the fertilizers, no ultimate ad- vantage could accrue from their application. The mixture of finely powdered raw phosphates with farm-yard manures, in a manner similar to that pointed out in our last chapter, is productive of excellent results. And their direct application in the same raw stute to lands of which the soils contain an abundance of sulphuric, liuraic, carbonic, or acetic acid, is also very successful. In each case, however, an impalpable state of powder and extreme Btate of division in the soil are absolutely indispensable. Although the principal sources from whence phosphates can be most economically obtained in this country are those just dealt with, it will be interesting for the sake of comparison, to introduce a table of analyses of the different qualities and forms produced and used throughout the world. (See page 66.) It will have been noticed that in all cases the chemical value of these bodies is determined by their percentage of phosphoric acid, and it is therefore advisable to here set forth an approximate trans- lation of the scientific formula by which the composition of a phos- phatic body is ascertained. The substance destined for examination is first treated with boiling nitric or muriatic acids, which dissolve all its active ingredi- ents, the parts remaining undissolved being composed principally of sandy and siliceous matter. The phosphoric acid, lime, iron, alumina, etc., etc., are all con- tained in the acid solution and are withdrawn from it and estimated, by adding to it other substances for which they have strong affinities, and with which they form insoluble salts. 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