vab3 CLASSIFICATION OF THE PUBLIC’ LANDS enor ee GEORGE OTIS SMITH AND OTHER3 YF eos SS OU par Pease HT Hew Dork State College of Agriculture At Cornell Aniversity Sthaca, N. D. Library Sornell University Lip HD 216,57°°72! University Libr DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY GEORGE OTIS SMITH, Director BULLETIN 537 THE CLASSIFICATION OF THE PUBLIC LANDS BY GEORGE OTIS SMITH AND OTHERS WASHINGTON GOVERNMENT PRINTING OFFICE 19138 SEPARTMENT OF FORESTRY N.Y, STATE COLLEGE OF AGRICULTURE CORNELL UNIVERSITY, ITHACA, Nu ¥s CONTENTS. The purpose of land classification ag Development of the Survey’s organization for land classification History and legal basis for land classification__ Introduction hand) SiwSeos2 shes oo soo aoe ee eee General divisions____-_-_-_--_-----_--_- Public-land laws _--_--_--------_-__-___ Agricultural-land laws _--------___- Purpose _-____--_--_--_--_--__- Homesteads ~_~--------------_-- Forest homesteads _-_--________ Enlarged homesteads_____--_--- Desert; land 222-222 22-- as 2k Reclamation act ------------_- eh Isolated tracts__.---_---------- Timber and stone lands_____-_-_ Mineral-land laws _-__------------- Coal-land Jaws--------------------- Laws relating to public and quasi-public uses____-_-_-_--_-- Rairodds.c2 oe ee ees See Saas Mining and milling ------------ Municipal uses___-------------- Land grants 222-s..254---+-- see nes Grants: to States_.......2---=-=-=~- In aid of schools and State inst In aid of internal improvements @arey Act. 2220252225 -seees Railroad grants___-.--------------- Necessity for land classification___--------- Agencies and methods of classification_-—--- Classification by affidavit of applicant__- Classification by deputy surveyors___--- FA Ge oe ome es: Classification by Land Office field service___------------------- Classification by the Geological Survey__ Historical sketch_________-_------------------------------ Qa, lands. 2. een ese tenes skee ee ee se eee sss ee Ol lamdS:.s2ne enna sss soe ole Phosphate lands _----_----------------------~------------- Potash lands _--_------------------ Metalliferous-mineral Jands_.----------------------------- 4 CONTENTS. History and legal basis for land classification—Continued. Agencies and methods of classification—Continued. Classification by the Geological Survey—Continued. Page. Water-power sites Sante == 41 Reservoir sites. 2.2 ee 42 Public water reserves______---__--.-----_--_.------------- 42 Withdrawal acts... 222225565 seo se nena hb ose ee ees 43 SG@paration sActsj2222 2.5 2- ee eek ee eee eel eee aSa soos 45 Desirable new legislation-_____-_-_-.------------------------- 46 Classification of mineral lands__..--------------~--------------------- 50 Bie, GE OOS eee ee ce tee a ree 50 Development <2 = oe a 50 Detailed survey___ S 53 Methods used when a topographic base is available________ 53 Methods used when a base map must be prepared_____-___- 54 Methods followed when the Land Office survey affords a PASOsMe phe be ee ie 58 Reconnaissance survey____-------_--------------------------- 60 Public-land surveys___---___--------------------------------- 61 Preparation of data for classification____________--__-------------_- 63 Coal landSivscecc ober ee a es ee eed ee ee 65 Purpose of classification. .< oes ecu seen et 175 Nonpower classification 176 Additional requirements to make power classification effective__. 177 Classification of lands as regards irrigability_.._.._..__.-__________ 178 Field, methods 2-0. - $e ‘oe G2 oz q3ag 430 dia os ‘ + SPpav] [VO Jo anjvA surmnduos ut Avarng [BoTsoToey) SeqvIg pelt), NOL YSd avy -9m0 DOLLARS PER AGRE valued accordingly. The average depth of coal in a forty that is crossed at an angle by the outcrop or the depth-contour lines is the depth at the geometrical center of the area underlain. CLASSIFICATION OF MINERAL LANDS. 93 If the dip of the coal bed whose value is given above had not been regular the rate of its diminishing value would have been 2500 = 500 =$1 for each 33$ feet, so that if the depth under a given forty averaged 1,600 feet, the value of the forty would be 1600 —500 $60— “aa, = $27. If more than one bed of coal underlies a 40-acre tract and the beds are not close together each one is valued independently and the value of the forty is taken as the sum of the value of the independent, beds. If several beds occur in a group a normal value is figured out for the group and this value is reduced according to the depth. In fixing the value of a group of dipping beds allowance is made for the change in the value of the group due to the lower beds passing below the 500-foot, line before the higher beds and reaching the depth limit before they do. Formulas have been worked out to facilitate the calculation of the value of beds involved in some of the more common types of computations in these cases are read directly from large diagrams. These diagrams contain so much matter that a reproduction of one of them (fig. 6) on the reduced scale necessary for publication in this bulletin does little more than give a general idea of their char- acter, particularly as they are too involved to permit their descrip- tion in a bulletin that is not intended to set forth details of classifica- sis ALLOWANCE FOR FAULTS. Faults—that is, breaks in the rocks involving a movement of beds on either side of the break—occurring in a coal field depreciate the value of the coal for mining and in places may render it entirely unworkable. Small faults may be disregarded unless they are so numerous as to render the coal expensive or difficult to mine. If, however, the throw of the fault is large—that is, if the edges of the beds that are broken have been so far separated by movement at an angle to the bedding that entries can not handily be driven from the coal on one side of the fault to the coal on the other—the value of the land is clearly less than that in which there is no fault, its smaller value being due both to the extra cost of recovery and to possible crushing of the coal along the fault planes. The price of coal in such places is determined by considering the two parts of any forty traversed by the fault separately, and giving the normal price to the part having the higher value and 40 to 95 per cent of the normal price to the part having the lower value. From the total thus obtained 5 to 15 per cent may be deducted to allow for crushing along the fault plane. 94 CLASSIFICATION OF THE PUBLIC LANDS. EFFECT OF INTRUSIONS. Intrusions of igneous rock may affect a coal bed favorably, as where they occur in sheets close above or below the coal and have had the effect of changing it from a bituminous or lower grade of coal to an anthracite. The physical character and B. t. u. value of such coals reflect amply the favorable results of the intrusion. More often the intruded masses of igneous rock are in the form of more or less vertical dikes that cut the bed in various directions. Obviously these dikes detract from the value of the bed by increasing the cost of mining, and an allowance is made in the final price in accordance with their character and extent. ALLOWANCE FOR OTHER FACTORS. In addition to the factors that have been specifically considered, many other factors are taken into account in valuing the land in any field. Of these the one for which the largest allowance is likely to be made is that of uncertainty. In some fields it has been possible to obtain measurements on the coal along its outcrop at points a quarter of a mile or less apart, and some of these measurements are supplemented by others made in drillings at points “ back ” from the outcrop, so that in such places it is possible to determine the “habit” of the bed with some degree of certainty. In other places, especially in coal fields covered with a blanket of glacial deposits, or in broad valleys where the coals are under an alluvial cover, or in other fields where, owing to almost continuous burning along the outcrops, it is difficult to get accurate information as to the thick- ness of the beds, an allowance is made for uncertainty—an allow- ance that may take the form of a greatly reduced estimated thickness of the bed or, as is more common, of a restriction of the assumed area of workable coal. It has been found that the coal of certain fields was originally deposited with more regularity in some belts and areas than in others, and in many places the coal was deposited with great regularity around the edge of a basin but not in its center. Allowance is made for the possible thinning of the coal in all such places if exact data are not at hand, and the tract is classed either as noncoal land or as coal land of the minimum value. Many other factors are taken into account, such as known poor roof or floor, which may seriously affect the cost of mining and the value of the coal in place. Allowance is made for the extra cost of mining beds that include partings by making deductions for partings, it being assumed that the extra cost due to the partings eats up the profits on an equal thickness of coal. CLASSIFICATION OF MINERAL LANDS. 95 REDUCTION FOR DISTANCH FROM RAILROAD. Distance from railroads very largely affects the value of coal land. In fixing the value of Government coal land, however, distance from railroads is not taken into account, their value being based on that of the coal itself, but, in accordance with the law, the price so fixed is automatically reduced one-half for all lands lying more than 15 miles from a railroad in operation. Some land that contains coal beds, though within 15 miles of a railroad, can not be reached by a rail- road switch without going either around or over a high moun- tain, so that by either route its distance from the railroad practically exceeds the 15-mile limit. Such land is treated as if it were beyond the 15-mile limit and its price is reduced one-half, though not below the legal minimum—$20 an acre. MAXIMUM PRICE. In view of the uncertainty that may exist concerning many features of an undeveloped coal field, even if the evidence seems conclusive that it contains a large volume of coal, the maximum price of coal land is fixed by the regulations at $300 a nacre, except that if the field in which the land is situated contains very large mines, and if the coal is well known in the market and its adaptability to different uses has been demonstrated, the price of the land is computed from the value of the coal it contains, whether -it exceeds $300 an acre or not. REVIEW OF CLASSIFICATION. According to the regulations the classification of any land as coal land is subject to review by the Secretary of the Interior, but the person making the application for review must present facts that show clearly and specifically that the land is not coal bearing in the sense of that term as it is defined in the regulations. The facts set forth in nearly all applications for review and reclassification of coal land simply show that no coal can be seen outcropping on or close to the land and that no coal has been found in drilling wells for water on or near the land. Before such applications are filed request should be made of the Geological Survey to state the basis of the classifica- tion, for a large percentage of the coal land has been classified as such because it is underlain by coal at depths of 500 feet or more, whereas the rocks at the surface contain no coal and may be of entirely different age from the underlying coal-bearing rocks. Data presented in a request for reclassification have determinative value only if they differ from data already in the records of the Geological Survey. 96 CLASSIFICATION OF THE PUBLIC LANDS. REGULATIONS FOR THE CLASSIFICATION AND VALUATION OF PUBLIC COAL LANDS. The following regulations were approved February 20, 1913, by Secretary of the Interior Fisher: Il. CLASSIFICATION. 1. Land shall be classified as coal land if it contains coal having— (a) A heat value of not less than 8,000 B. t. u. on an air-dried, unwashed or washed, unweathered mine sample. (b) A thickness of or equivalent to 14 inches for coals having a heat value of 12,000 B. t. u. or more, increasing 1 inch for a de- erease from 12,000 to 11,000 B. t. u., 1 inch for a decrease from 11,000 to 10,500 B. t. u., 1 inch for each decrease of 250 B. t. u. from 10,500 to 10,000, and 1 inch for each decrease of 100 B. t. u. below 10,000. (c) A depth below the surface for a bed of coal 6 feet or more thick of not more than 100 feet for each 300 B. t. u. or major fraction thereof, and for a bed of minimum thickness for that coal a depth of not more than 500 feet, and for beds of any thick- ness between the minimum and 6 feet a depth directly propor- tional to that thickness within these limits, provided that, if the coal lies below the depth limit but within a horizontal distance from the surface not exceeding 10 times the depth limit, or if its horizontal distance from the foot of a possible shaft (not deeper than the depth limit) plus 7.5 times the depth of such shaft does not exceed 10 times the depth limit, the land shall be classified as coal land; provided, further, that the depth limit shall be com- puted for each individual bed, except that where two or more beds occur in such relations that they may be mined from the same opening the depth limit may be determined on the group as a unit, being fixed at the center of weight of the group, no coal that is below the depth limit thus determined to be considered. 2. Classification shall be made by quarter-quarter sections or surveyed lots, except that for good reason classification may be made by 24-acre tracts or multiples thereof described as minor subdivisions of quarter-quarter sections or rectangular lotted tracts. II. VALUATION. 8. For purposes of valuation the price per ton for a noncoking, nonanthracite coal 6 to 10 feet thick shall be one-tenth of a cent for each 1,250 B. t. u.: (a) Provided that the price per ton may be increased by not more than 100 per cent if the coal is coking, smokeless, or anthracitic or has other enhancing qualities; or it may be decreased for high sulphur or ash, friability, or nonstocking or other qualities that reduce the value; and (0) Provided, further, that if the coal in one bed is over 10 feet thick the price on each foot above 10 feet shall be reduced 1 per cent for each such foot (thus the reduction will be 1 per cent on the eleventh foot, 2 per cent on the twelfth foot, and so on); or if the coal is less than 6 feet thick the price shall be reduced by CLASSIFICATION OF MINERAL LANDS, 97 multiplying the normal value by ate where ¢ equals thickness in feet; and (c) Provided that where the thickness of any bed varies irregu- larly its computed thickness (CT) over any area shall be equal to the average of the measurements (AM) less the sum of the differences between each measurement and the average of the measurements (SD) divided by the sum of the measure- ments (S): oT=am—SD 8 4. The value of any acre within 15 miles of a railroad in operation shall be determined at the rate per ton prescribed above on an estimated recoverable tonnage of 1,000 tons to the acre-foot: Provided that if the coal is in several beds having an aggregate thickness of more than 10 feet if beds less than 6 feet thick are considered at the reduced thickness as prescribed above, the value due to each foot above 10 feet shall be reduced 1 per cent for each such foot (as in computing the price per ton on a single thick bed) up to a thickness of 80 feet, above which any addi- tional thickness shall be valued at 30 per cent of the normal value. 5. This price shall be decreased one-half if the land is more than 15 miles from a railroad in operation, or if it is within that limit but inaccessible owing to topographic conditions; but no land shall be valued at less than the legal minimum price, nor shall the price of any land exceed $800 an acre except in districts which contain large coal mines and where the character and extent of the coal are well known. 6. Within the above restrictions a graded allowance shall be made for increas- ing depth, and allowance may be made for any special conditions enhancing or diminishing the value of the land for coal mining. 7. If only a part of a smallest legal subdivision is underlain by coal the price per acre shall be fixed by dividing the total estimated coal values by the number of acres in the subdivision, but this price shall not be less than the minimum provided by law. 8. When lands which were at the time of classification more than 15 miles from a railroad are brought within the 15-mile limit by the beginning of opera- tion of a new road, all values given in the original classification shall be doubled by the register and receiver. 9. Review of classification or valuation may be had only on application there- for to the Secretary, accompanied by a clear and specific statement of conditions not existing or not known to exist at the time of examination. RESTORATION. After the classifications and valuations are completed the lands are restored to entry. Those that contain no coal resume the status that they had prior to the withdrawal. The coal lands, after restoration, may be acquired under the coal-land laws at the valuation prices, surface entry under the agricultural-land laws and the State selection 78894°—Bull. 587—13——7 98 CLASSIFICATION ur HH PUBLIC LANDS. acts being permitted at any time prior to their alienation under the coal-land laws. A typical order of restoration is given below. DEPARTMENT OF THE INTERIOR, Unitep STATES GEOLOGICAL SURVEY, Washington, February 12, 1918. The honorable the SECRETARY OF THE INTERIOR. Sir: The classification of the lands listed below, which are included in an existing withdrawal, has been completed and reported to the Land Office, and I therefore recommend the submission to the President, for appropriate action, of the following order of restoration, involving 264,009 acres, all noncoal. These lands are not included in petroleum or phosphate reserves or in national forests, but part are within a power-site reserve. Very respectfully, Gro. Otis SMITH, Director. Fresrusgy 18, 1913. Respectfully referred to the President with favorable recommendation. WaALTER L. FISHER, Secretary. ORDER OF RESTORATION. Coal-land restoration—Idaho No. 10. So much of the order of withdrawal made heretofore for the purpose of coal- land classification, namely, Idaho No. 1, as affects the lands hereinafter described ig hereby revoked for the reason that the Director of the Geological Survey has classified these lands. This revocation does not affect withdrawals or reserva- tions other than as above set forth. Boise meridian. T. 85 N., R. 1 E., all of township. [Here follows the remainder of the land description.] Wm. H. Tart, President. FEBrvuaArRY 18, 1913. FIELD WORK ON COAL LANDS. GENERAL NATURE OF THE WORK. The second general step in the process of classification is to obtain in the field the information there available that is necessary for the classification. Field work that is done expressly for the classifica- tion of coal land involves all research that is made in general geologic field work but gives special weight to certain factors. The informa- tion needed for classifying coal land relates to (1) location, (2) stratigraphy, (3) horizontal extent and thickness of coal beds, (4) vertical position, and (5) quality of the coal, These may be taken up in turn. CLASSIFICATION OF MINERAL LANDS. 99 LOCATION. In work done for classification all the points or features concern- ing which information is obtained in the field must be accurately located with reference to the land lines, for if locations are not exactly specified the information is of little value. For example, a geologist may study an outcrop of a 30-foot bed of coal, measure its sections, photograph it, and sample and analyze the coal to determine its quality or test it in any other way, but if, when he has done all these things, he can not tell whether the outcrop is im sec. 31 or sec. 32 of a given township, the information he has gathered is entirely valueless for purposes of classification. It is therefore necessary that all the features to which his information relates be accurately - located on his field maps, with special reference to township and range lines, section lines, and quarter-section lines, and even accu- rately within the 40-acre tracts, as it is desirable to know exactly how many acres of the forty are underlain by coal in order to determine the value of that particular forty. The methods of survey by which the geology is tied as accurately as possible to the public- land net have been described in a preceding chapter. STRATIGRAPHY. The first purpose of gaining a thorough knowledge of the stratig- raphy is to be able to recognize groups of rocks that are coal bear- ing elsewhere or to recognize other rocks that the wide experience and knowledge now available concerning the geology of the Western States have shown not to be coal bearing. The second purpose is to determine, from such data as may be obtained on the surface, the “lay ” or structure of the coal-bearing formation and the groups of coal beds it contains. Just as in the Eastern States it has been found that workable coal beds are confined to a particular part of one large group of rocks, which has long been designated the “coal measures,” so in the West it has been found that workable coal beds are confined to relatively few groups of rocks, which are separated usually by great thicknesses of other rocks that are nowhere known to contain workable coal beds. As the sedimentary rocks of the West consist mainly of sandstones, shales, and limestones, those of like lithologic character being simi- lar to one another in general appearance, the particular sand- stones and shales with which the coal beds are associated can as a rule be distinguished only by means of the fossil plants or animals that are associated with them. Thus it has been found necessary to employ the services of several experienced paleontolo- gists to examine the fossils associated with the rocks and from these fossils to determine the age of coal-bearing formations. 100 CLASSIFICATION OF THE PUBLIC LANDS. The first step of the geologist who has been sent into a field or area that is known or has been reported to contain workable coals is usually to determine what groups of rocks occur in that region and then, knowing the groups of rocks that contain workable coal beds in other places, to concentrate his attention on those groups, hunting for coals in them. Having found the coals his next work is to determine the number of groups of coals, as the same territory may contain two or three or even more coal-bearing formations, though usually they occur in different parts of the same field. His next step is to examine the several coal-bearing formations in order to determine, if possible, the number of coal beds in each. This work naturally leads to the determination of the areal extent and thickness of the beds. EXTENT AND THICKNESS OF COAL BEDS. Coal is a rock that has been formed from vegetal matter. The vegetation may have grown where the coal bed is now found, much as it grows in the great peat bogs of Europe or some of the large swamp areas of this country, or it may have been washed or drifted from the place where it grew to the place where it now occurs as coal. In changing from a mass of decaying vegetal matter to a bed of coal its volume has decreased and its weight per cubic foot has greatly increased. It has also lost many of the elements of the* plants, es- pecially the moisture they contained, and if during its formation the coal bed was inundated by muddy waters its vegetal matter may have been overlain or intermingled with sand or mud. This material may have been added in small quantities at frequent inter- vals, simply rendering the coal “ dirty,” or it may have come in at long intervals and then in large quantity so as to form a blanket of mud or sand, which, being covered by renewed accumulations of vegetal matter, becomes a parting of clay or sandstone in the coal bed. In a few places a single coal bed has been deposited in a formation, and thousands of feet of other rocks have been laid down beneath and above it, no other coals having been formed. More fre- quently, however, where coal-forming conditions have existed they seem to have recurred in such a way that a succession or series of coal beds are laid down in the same area. In one region most of the coals in a group deposited in that way may be thicker in the same general area, and all the beds may tend to thin away from that area. In another region one bed of a group may be thicker in one locality and a higher bed of the same group may be thicker in another locality. Coal beds vary greatly in extent, ranging from pothole fillings having about the shape though not the size of a kettle to flat- lying beds thousands of square miles in extent. In Missouri a num- ber of coal beds have a thickness in places of 90 feet or more and CLASSIFICATION OF MINERAL LANDS. 101 an areal extent of only a few hundred feet or less, being simply fillings of deep holes in the rock, similar in shape to the “ pot- holes” that are so abundant around some waterfalls. In other places, as in the Sharon field of Ohio, the coal bed has the shape of a valley, with branches where side streams have come in, and a single mine may follow one of these valleys for some distance, the coal being confined to a width of perhaps a few hundred yards but extending indefinitely up and down the valley, which in some places winds tortuously. In still other places, as in the Block coal field of Indiana, the coal occurs int a succession of shallow basins, the beds having a thickness of 3 to 5 feet in each basin and thinning out to a few inches between the basins. The bottoms of the basins lie 20 to 30 feet below their rims. Some of these basins are so small and so close together. that the coal from-several of them is extracted by a single mine, the entries being cut through the rock from the lower level of one basin to the lower level of the next basin. Other basins have a length of 3 or 3 miles in a northwest- southeast direction and a width of one-half mile or more. Some of the individual beds can be traced from basin to basin and clearly recognized by peculiarities in the coal. In other fields the coal ap- pears to have been deposited unevenly in little depressions that are scattered irregularly over a large territory and li at various levels, so that it is not possible to trace a bed from. one point to another, and each little basin must be considered as a unit. From these types of irregular and narrowly limited coal beds every gradation may be found to some of the relatively even and continuous beds of the West, the extensive beds of the central interior coal fields, or the Pittsburgh and other beds of the East, which have an outcrop line hundreds or even thousands of miles in extent and were laid down in a more or less continuous sheet, many of them covering thousands of square miles. Thus the Pittsburgh bed has a known extent of over 6.000 square miles and is found in isolated areas beyond the limits of the main bed. Other Appalachian coal beds are of much greater extent, some of them, as the Lower Kittanning, having many times the areal extent of the Pittsburgh bed, though not its regularity. Certain coal beds in the Illinois fields have been traced without question as to their identification over a large part of that State, through a portion of western Kentucky, and through the entire length of the Indiana coal field. It is believed that many of the coal beds of the Western States are also traceable over large areas. Most of these widely extended coal beds have certain slight but definite features or peculiarities or are associated with other rocks of dis- tinctive character, so that it is possible to recognize them at any point. The peculiarity of a bed may consist of some particular type of parting or arrangement of partings which may hold for long dis- 102 CLASSIFICATION OF THE PUBLIC LANDS. tances, or it may consist of the presence just above or below the bed of a stratum that has easily recognizable characteristics. In order to trace and identify some coal beds it is necessary to study their rela- tions to one another. One of the main reasons for studying the stratigraphy is to identify if possible at the outset the group of coals studied, and in this work note should be taken of the determinations reached by the wide study of the same formations in previous seasons. For example, in the great coal field that covers much of western North Dakota and part of South Dakota, all of southeastern Montana and the great Powder River field of Wyoming, there are two coal- bearing formations—the Fort Union above, named from its early recognition at Fort Union in North Dakota, and the Lance forma- tion below, named from the occurrence of those rocks on Lance Creek in Wyoming. The Fort Union coals are as a rule persistent; they have local thicknesses of 10 to 30 feet or more, and some of them can be traced for hundreds of miles along their outcrop, and individual beds can be recognized from point to point. On the other hand, the Lance coals occur as a rule in small lenses, most of them a fraction of a mile or a very few miles in extent. The coal in these lenses ordinarily is but little above the minimum workable limit and thins rapidly to nonworkable thickness in all directions. If the geologist knows that the coals in any particular area are in the Fort Union or Lance formation he knows what to expect concerning them, for if he finds that they are of Lance age and he is studying at the moment the coal at a point where it is workable, he is careful to trace it if possible in order to see how far it may extend before it becomes unworkable, so as to determine as closely as practicable the extent of that particular lens. If, on the other hand, he knows that the coal before him is of Fort Union age he attempts to de- termine, if possible, what particular coal bed in the Fort Union it is, and, assuming that he will find that same bed in a large part of the country ahead of him and that he will judge of its thickness by com- bining a great number of measurements made over a large territory, he does not with the same attention attempt to discover whether the coal pinches out a short distance on either side of the point where he is standing. In all of this work it is, of course, not safe to assume too much, for toward the south end of the Powder River field the beds of coal in the Lance formation increase in extent and thickness, so that they more nearly resemble those of the Fort Union formation, farther north. It is not advisable to assume absolutely that, because in some area already examined a coal bed is very extensive and keeps the same thickness with great regularity, it will continue to be extensive and regular in territory that may be studied later. For example, the Pittsburgh bed, which maintains a very uniform thickness over a CLASSIFICATION OF MINERAL LANDS. 103 large area in western Pennsylvania, becomes very irregular in south- ern Ohio, so much so that it has been wrongly identified, and it is only within a few years that the bed there identified as the Pitts- burgh has been shown to be another coal higher in the series. Like- wise, in the Illinois-Indiana field coal V, which is probably the most persistent bed in that field and can be traced along its outcrép for thousands of miles with great regularity, pinches out in parts of Greene County, Ind., close to other localities where it shows its greatest thickness; and, again, in Warrick County it loses its usual characteristic roof and is split into two distinct beds. In the same way many of the coals in the West that on casual scrutiny appear to - be persistent prove, when studied in detail, especially in connection with mining operations or where close prospecting has been done with a drill, to vary considerably both in thickness and in distance apart. For example, at Castlegate, Utah, four beds are at one point separated by 50 feet, 20 feet, and 14 feet of strata, whereas a short distance away these intervening rocks pinch out and the four beds, which separately are on the average only about 3 feet thick, come together to make a single bed 12 feet thick. Drilling in that field has shown that all the beds tend to be very irregular, splitting and combining again and changing in thickness, so that in tracing them from drilling to drilling it may be found that though each core shows certain workable beds, yet a bed that is thick at one point is thin at the next. Detailed work in many of the eastern fields where extensive mining operations have afforded minute data in regard to the coal, or where thousands of dollars have been expended in Grilling, has shown that even the most persistent of the beds are sub- ject to variations, so that a bed which can be traced from one mine to another over a whole county and which. may show a variation of only a few inches from mine to mine may suddenly, in mining parlance, “go to pieces.” It is therefore the special work of the field geologist not only to locate the coal on the ground but to make as detailed a study as possible of its thickness and extent in order to learn just how far it maintains a workable thickness, how per- sistently it maintains a given thickness, and whether it is likely to vary greatly from point to point and also to determine, so far as he can, any or all of its features. Space does not permit the detailed de- scription here of all the possible irregularities that may occur in a coal bed, for which the field geologist must be on the lookout. In some fields the coal beds are exposed in cliffs or steep slopes in such a way that the coal may be seen almost continuously for many miles. In such places the geologist takes the opportunity to make a careful study of the regularity or irregularity of the coal beds with reference both to their thickness and to the variability or regularity 104 CLASSIFICATION OF THE PUBLIC LANDS. in thickness and in character of the intervening rocks and of the spaces between the beds. In regions in which the beds are not well exposed it may be possible, from a knowledge of the position of a bed with reference to other rocks which show on the surface, to determine exactly the position of the particular coal under considera- tion and, by means of a very small amount of digging, to expose the bed so that its thickness and partings can be measured. In some coal fields hundreds of such openings have been made in the study of the bed. In other fields the beds occur in rocks that weather down to soils rapidly, and it may be only where a coal bed crosses a stream or is otherwise exposed that it can be located or seen. It may be difficult to trace such a bed from point to point, and in some places where exposures are several miles apart it may be difficult or impos- sible to determine exactly its position. In other places beds may be traced readily, but the fact that they have been burned continuously along their outcrops makes it difficult to get accurate information concerning their character and thickness. It is of course possible to map the position of the coal bed in such places and it is then neces- sary, from such information as can be obtained concerning the thick- ness and character of the coal, to infer its character at points between these places. It is especially in such areas that a general knowledge of the “habits” of the bed or group of beds assists in their classifica- tion, for if it is known that a particular bed, whose burned outcrop has been traced with detailed measurements perhaps at only one or two places in a township, occurs at a certain horizon in a certain formation, it is possible to surmise whether it is regular or irregu- lar in the broad area between these exposures, where no information on the bed itself can be obtained. Again, it may be possible, by mak- ing a careful study of a coal in a mining region, to apply the infor- mation to a wide area where but scanty information on the coal itself can be obtained. Wherever the coal is exposed the field man makes careful examination and measurement of every possible sec- tion, measuring down to the fraction of an inch, even though, where the bed is irregular, it is recognized that another measurement made a short distance away may be quite different. Where a bed is irregu- lar special effort is made to obtain as many measurements as possible; in order to obtain average figures for use in the classification and valuation of the land underlain by that bed. In some places where the data are very meager, as in regions where the rocks crum- ble to soil and the land is largely meadow land, considerable time has been given to making openings on the coal because of the neces- sity of having actual information and measurements as a basis for classification. CLASSIFICATION OF MINERAL LANDS. 105 ATTITUDE AND DEPTH OF THE COAL. As already stated, the coal throughout wide areas lies entirely below the level of drainage—in places hundreds or even thousands of feet below—and the outcrops of the particular coal beds on which land is classified as coal land may be scores of miles away. It there- fore becomes necessary for the field man to determine as accurately as possible not only the position of the coal outcrop with reference to the land lines and the thickness of the coal as exposed along the outcrop or the extent of the lenses, but also the depth of the bed beneath the surface and its attitude as it dips into the basin. He does this, first, by studying the inclination of the coal beds where they dip into the ground and, next, by studying the inclination and thickness of the other rocks that overlie them. As coal beds lie more or less nearly parallel, with layers of sandstone, shale, and limestone, one of his duties is to determine how nearly the coal beds are parallel with these other rock layers. If he finds by observation at many points that there is very little variation in the interval, say 300 feet, between a limestone bed above and the coal bed that he is studying, he may assume that the dip of that limestone bed measured possibly at a point a mile back from the outcrop of the coal indi- cates the dip of the coal beneath that point at a level 300 feet below the surface. If, again, he finds that some other rock bed a thousand feet above the coal bed is parallel to it, he may assume that a measure- ment of the dip of that bed taken 5 or 10 miles back from the coal outcrop may indicate rather closely the dip of the coal bed itself 1,000 feet below. Hence the field geologist must not only study the details of the coal bed along its outcrop, but must also study the geology of the area back of that outcrop, especially with reference to the dip of the rocks. If, as sometimes happens, he finds that the space between a coal bed and the overlying rocks is variable, he can not compute the depth of the coal bed so closely. In some places all the rocks associated with certain coal beds, having the same great folds and basins, have been overspread by a blanket of other rocks that do not have the same structure. Such a blanket may completely hide not only the coal-bearing formation but the other formations that are associated with it and that have been folded in the same way. In such places it is only possible to infer from broad general knowledge of the field how deep the coals may lie below the surface. QUALITY OF THE COAL. The character and quality of a coal can be determined in part by a simple examination of the coal bed. Thus it is possible in most examinations to determine whether a coal is a lignite, a subbitumi- 106 CLASSIFICATION OF THE PUBLIC LANDS. nous coal, a bituminous, a cannel, or an anthracite coal. It may also be possible to estimate rather closely whether or not a coal contains a large amount of ash. Where small mines or prospects have been opened it may be possible, by studying the coal on the dump, to determine whether the coal can be shipped or stocked, or the extent to which it tends to crumble under the action of the atmosphere. The final tests, however, are the chemical test, consisting of an analysis of the coal, which shows fully its percentage of the various heat-giving elements and of the ash and other elements that do not yield heat but detract from its value, and the test of its heat-giving value in the calorimeter. Experience has shown that coal of certain kinds—especially low-grade coal—changes in chemical composition very rapidly when exposed to the weather, so that in getting samples for analysis it has been found necessary, in order that the samples may be fairly compared and may form the basis of a uniform system of classification and valuation, that they be taken with great care in a uniform manner and that the treatment of each sample from the time it is taken until it is analyzed shall follow certain standards. To this end certain regulations have been prepared in regard to the method of obtaining coal samples for analysis and are consistently enforced. These regulations in brief are as follows: 1. Select a fresh face of unweathered coal at the point where the sample is to be obtained and clean it of all powder stains and other impurities. 2. Spread a piece of oilcloth or rubber cloth on the floor so as to catch the particles of coal as they are cut and to keep out impurities and excessive mois- ture where the floor is wet. Such a cloth should be about 14 by 2 yards in size and should be so spread as to catch all the material composing the sample. 3. Cut a channel perpendicularly across the face of the coal bed from roof to floor, with the exceptions noted in paragraph 4, of such size as to yield at least 6 pounds of coal per foot. of thickness of coal bed; that is, 6 pounds for a bed 1 foot thick, 12 pounds for a bed 2 feet thick, 24 pounds for a bed 4 feet thick, ete. 4, All material encountered in such a cut should be included in the sample, except partings or binders more than three-eighths inch in thickness and lenses or concretions of “sulphur” or other impurities greater than 2 inches in maximum diameter and one-half inch in thickness. 5. If the sample is wet, it should be taken out of the mine and dried until all sensible moisture has been driven off. 6. If the coal is not visibly moist, it should be pulverized and quartered down inside the mine to avoid changes in moisture, which take place rapidly when fine coal is exposed to different atmospheric conditions. The coal should be pul- verized until it will pass through a sieve with one-half inch mesh, and then, after thorough mixing, it should be divided into quarters and opposite quarters re- jected. The operation of mixing and quartering should be repeated until a sample of the desired size is obtained. When the work has been properly done a quart sample is sufficient to send for chemical analysis. This sample should be sealed in either a glass jar or a screw-top can with adhesive tape over the joint and sent to the chemical laboratory for analysis, CLASSIFICATION OF MINERAL LANDS. 107 Since the value of the land varies with the quality of the coal as determined by the chemist, his methods are briefly described here. Immediately after the sample is received at the laboratory it is weighed and placed in a shallow tin pan in a large drying oven, in which a temperature of 30° to 35° C. is maintained. The sample remains exposed to currents of warm air in the oven until the loss between two successive weighings made six to eight hours apart does not vary more than 0.2 per cent. The loss of weight in the oven is called air-drying loss. After being air dried the sample is crushed to a fine powder and thoroughly mixed. To determine the amount of moisture remaining in the coal after air drying, a 1-gram sample is heated for an hour at 105° ©. and then cooled in a desiccator over sulphuric acid. The moisture in the sample is thus driven off, hence the percentage of loss represents the percentage of moisture in the coal. The remain- ing part of the sample is next used to determine the amount of ash in the coal. This determination is made by slowly heating the sample in a muffle furnace until all of the combustible matter is burned off. The remainder is ash. The volatile matter is deter- mined from a fresh 1-gram sample in a 30-gram platinum crucible, with a close-fitting cover, heated for seven minutes over a Bunsen flame 20 centimeters high. The loss in weight minus the moisture at 105° C. is the weight of the volatile combustible matter. The sulphur is determined on a separate example by what is known as the Eschka method. The percentage of fixed carbon given in the analysis is the difference between 100 per cent and the sum of moisture, volatile combustible matter, and ash. The calorific value of a coal, or the amount of heat that can be obtained from it, is the most important factor in classification and valuation. The calorific value of coal is determined with a bomb calorimeter. The following is a brief description of the details of operation: A 1-gram sample of coal (60-mesh) in a platinum tray is placed in the bomb and the lid is screwed down tightly against a lead gasket. Oxygen is forced into the bomb until the pressure is 18 to 20 atmospheres. The bomb, filled with oxygen, is placed in a brass bucket containing distilled water, the bucket having been previously placed in an insulated jacket. The coal is ignited by electric current and is burned at once. The heat of combustion is transmitted through the walls of the bomb and is manifested in a rise in the temperature of the water. This rise in temperature is measured by a very delicate thermometer. The 1The methods of analyzing coal and coke are fully described in Technical Paper No. 8, Bureau of Mines, by Frederick M. Stanton and Arno C. Fieldner. The method outlined here is summarized from that paper. 108 CLASSIFICATION OF THE PUBLIC LANDS. quantity of heat given off by the burning of the coal is determined by multiplying the product of the weights of the metal and water in the apparatus and their respective specific heats by the rise in temperature. The result thus obtained is calculated into terms of calories and British thermal units. PREPARATION OF MATERIAL. The preparation of material by the field man, so that it may be considered to the best advantage in the work of classification and valuation, has already been considered in the chapter entitled “ Prepa- ration of data for classification,” immediately preceding the discus- sion of the classification of coal lands. PROCEDURE IN CLASSIFICATION AND VALUATION. In the actual work of classification of coal lands each area under consideration must be treated individually, yet in general a definite line of procedure is followed. The first step is to assemble all the available data, including not only the maps and reports of the geologists who may have made a special examination of the field, but the reports of any special agents of the Land Office who have been in that field, as well as all reports of geologists who may have visited the field at some earlier time (prob- ably for some other purpose) and all other available information concerning the land or the coal it may contain. The land-classifica- tion board has a system of graphic records which show at once the existence of any reports on the field and give references to them, so that when the case is taken up all the data available are at hand. As a matter of fact the field man will usually have familiarized himself with all these earlier data and will be prepared to present them as may be necessary. The second step is to scrutinize carefully all these data, and by their aid to take the action or to obtain the information listed under the following heads: 1. The number, names, character, and other features of the coal- bearing formations are determined. As most of these formations extend over large areas, some of them crossing several States, a gen- eral knowledge of the formations at once suggests the probable con- ditions to be found in the field studied, and that general knowledge may strongly affect the action to be taken in classification and valuation. 2. The number of coal horizons or groups of horizons is ascertained. 3. The thickness of each coal bed over the field is determined, if it can be traced. If each bed can not be traced the group of coals CLASSIFICATION OF MINERAL LANDS. 109 is studied as a whole to determine from point to point the number of beds and their aggregate thickness and value. 4, The basing value per ton of the coal is computed by comparing its analyses and its obvious character with the standard scale. An average B. t. u. value having been. fixed for the coals of the field or for the different groups of coals, the other qualities of the coal— such as its adaptability to coking or to stocking—are studied to de- termine whether they enhance that value or detract from it, and the price is raised or lowered accordingly. 5. If the field is small and the data are scattered the field may be studied as a unit. If the data are abundant in any township the coals in that township are studied by themselves, and, exceptionally, the variation in thickness may make it necessary to divide a town- ship into belts or areas, in each of which a basing value of the groups is determined. 6. All sections of the coal are examined, and if the coal beds are split the equivalent thickness of a solid bed is computed and a memo- randum of the results is placed beside the drawn section. Then further reduction is made for the reduced value of the bed, if it is less than 6 or more than 10 feet thick. If a bed is variable in thick- ness but varies so regularly that lines of equal thickness can be drawn on a map of the field these lines are so redrawn as to indicate the reduced thickness determined by allowance for their reduced value if the thickness is less than 6 or more than 10 feet. If the beds are of irregular thickness the average of the measurements taken is ob- tained, and by the use of the “ modulus of irregularity ” a computed average thickness is obtained for use in valuation. 7. The outcrops of the coals are examined to determine which are workable coals and especially to make note of the outcrop of the lowest bed or the bed covering the largest area. Where the coal lies in one or more lenses a computation of its gradation in thickness is made between points at one of which the coal is below the minimum thickness and at the other is above, to determine the position of the minimum. The limits of workable coal having been determined for certain points, the limits of the lenses of the coal are drawn on the maps. For isolated measurements at points where the bed is above the minimum limit the extent and character of the several lenses measured are determined, special formulas being applied where possible. me 8. If the coal passes below the depth limit of workable coal the position of that limit is determined and indicated on the map. 9. The limit of workable coal having now been determined, a line is drawn on a plat along the 40-acre lines, or, where necessary, along the 10, 5, or 24 acre lines in the forty, to separate the area that con- 110 CLASSIFICATION OF THE PUBLIC LANDS. tains workable coal from the area that does not contain workable coal. The latter area is then plainly marked “noncoal,” and if the land is only to be classified and not valued a copy of the plat is made on a blank township sheet to show accurately the coal land and the noncoal land. This copy, after checking and proper designation, is dated and signed by the members of the coal section of the board. Its later history is the same as if valuation had been made. 10. The tract or township may now be valued. The particular steps at this point may vary greatly, depending on the complications involved in the valuation. It may be that the coals are of a grade so low that, like the low-grade lignites, regardless of their thickness, they will be valued only: at the minimum. Or it may be that the tract contains only one thin bed that lies flat and at slight depth, so that the land may be valued at the minimum or perhaps at a uni- form price. From these simple conditions there will be conditions grading in complexity all the way to those found in such fields as, for example, the Rock Springs field of Wyoming, where there are three groups of beds of coal of different age, character, and quality, each group containing from six to eighteen coal beds, and where each coal bed has been accurately traced by means of hundreds of measure- ments made on the coal in each township, both along the outcrop and in mines and drillings. Owing to differences in quality and thickness coals have different depth limits. They may also vary in dipand may be locally broken by faulting or by igneous intrusions. The value of the land that is involved in these complications is computed by using printed blanks that contain columns arranged to show not only the observed data on each bed in each 40-acre tract, but also the com- puted values of each bed, ending with the computed value of the 40 acres. This completed blank becomes part of the permanent record, so that, if additional data are obtained or if for any reason the valu- ation should be reviewed, it shows not only the field data but the steps that have led to the final result. As values are determined they are recorded on a blank township sheet and if the data are abundant and complicated the coal boundaries may be drawn on transparent over- sheets, on which the computed valuation prices are placed. This sheet is properly labeled, dated, and signed by the members of the coal section. 11. As the land in a township is classified and valued memoranda are prepared to show the basis for any criteria used, and all these memoranda, with pee forms showing the computations and allow- ances, are retained as “minutes” and, when reviewed and signed by the members of the coal section, form a part of the permanent record. OIL AND GAS LANDS. 111 PROGRESS IN CLASSIFICATION AND VALUATION. The following statement shows the status of the work of classi- fication on January 1, 1913: Progress of coal-land classification to January 1, 1913. Total withdrawals_______..-__- acres__ 128, 147, 312 Area classified and valued as coal land_______ do_--_ 16, 433, 817 Area classified as coal land, price not fixed___do____ 841, 706 Area classified as noncoal land______________ do__._. 42, 244, 682 Restored without classification______._______ do____ 2, 717, 895 Total restorations___.__________________ do___- 62, 237,600 Total withdrawals less total restorations (total out- standing withdrawals) _--_________-_______ acres__ 65, 909, 712 Value of coal land at classified price_______________ $702, 157, 268 Value at minimum price__________________________ $279, 122, 661 OIL AND GAS LANDS. OCCURRENCE OF OIL AND GAS. To the minds of many people who find little difficulty in compre- hending a classification of lands containing deposits of coal or phos- phate the possibility of applying a similar classification to lands containing oil and gas, especially in advance of actual drilling, appears uncertain, to say the least, and, according to the nature and experience of the individual critic, such a classification is looked upon either as a more or less scientific guess or as evidence of the possession of supernatural powers by the classifier. The classification of oil and gas lands, however, calls for the use of no mysterious or haphazard methods but is based on detailed field examinations, followed by careful consideration of all the available facts, geologic and economic, in their relation to one another and to the known principles of the occurrence of oil, which have been proved again and again in the development of oil fields throughout the world. Although the ulti- mate test of the presence of oil in commercial quantities is made with the drill, it is nevertheless a fact that the intelligent application of the principles of oil accumulation to the geologic facts observed will indicate at least the areas where no oil will be found and will go far toward delimiting the areas where production is reasonably certain. To the classifier of oil lands, as to the oil-well driller, the theories proposed to account for the origin of oil and gas are of only inci- dental interest; the problem of prime importance to him comprises the assignment of proper values to the many factors which influence accumulation and the determination therefrom of the present posi- tion and extent of the deposits. 112 CLASSIFICATION OF THE PUBLIC LANDS. Oil and gas are composed for the most part of carbon and hydro- gen, but they vary greatly in the proportions of these elements and in the way in which they are combined. The petroleum oils range from low-grade heavy oils containing much asphalt to high-grade light oils which contain a large percentage of paraffin and volatile constituents and little or no asphalt. The heaviest oil is chiefly valu- able as fuel, for which it is used in its crude state. Progressively lighter oils are used less and less for fuel and more and nfore for the other products that are obtained from them. There is a general opinion that weight for weight the fuel value of light and heavy oils is about equal, but because of the value of the distillates from the lighter oils it may be stated in general that the lighter the oil the greater its value. In classifying lands as to their probable content of oil and gas it must be borne in mind that oil and gas are mobile substances and that, owing to their mobility and to the resulting increased impor- tance of gravitation, temperature, hydrostatic pressure, and capil- larity, it is necessary to make certain variations from the type of procedure employed in classifying lands containing coal, phosphate, or other stable minerals. The mobility of oil and gas has, in many regions, permitted their migration through varying thicknesses of pervious strata to their present places of accumulation, so that the problem is not to discover where the hydrocarbons originated but rather where they have accumulated. The present position of these accumulations depends mainly on the character of the strata, the attitude of the strata (commonly spoken of as the rock structure) , the presence or absence of water, and the character and specific gravity of the oil. The fluid hydrocarbons do not, as is supposed by some, occupy underground lakes or reser- voirs surrounded by walls of rock. Instead they saturate porous rocks in places where the geologic structure, the conditions with regard to underground water, and the succession of strata are such that the accumulations are sealed by relatively impervious beds. Thus, although the accumulations of oil or gas are called “ pools,” they are not to be confused with such, pools as are formed by the collection of liquids upon the surface of the ground. The porous stratum in which the hydrocarbon collects is often spoken of as an oil or gas “sand,” although it may in reality be sandstone, gravel, limestone, or a zone of fractured rock. Into this “sand” the hydro- carbon comes from’ one or another source, but if there is to be an accumulation of importance the migration of the oil or gas along this pervious bed must be stopped by a change in dip or by some other obstacle to continued progress, and, in addition, the reservoir thus formed must be sealed by strata that are relatively impervious, OIL AND GAS LANDS. 113 such as compact shales, clays, or fine-grained sandy beds saturated with water. The accumulations within the United States may be divided roughly into three classes, as indicated below. 1. Those occurring in strata of sandstone or limestone bounded above and below by rocks comparatively impervious to oil. The sandstone or limestone may be of broad or of very narrow extent, in some places comprising merely small lenses of porous material embedded in relatively impervious rocks, in others underlying hun- dreds of square miles of territory in comparatively regular beds. To this class belong the greater number of oil accumulations of this country. 2. Those occurring in porous strata, apparently lenticular, asso- ciated with the “salt domes” of the Gulf Coastal Plain. 8. Those occurring in fissures in shale, as in the Florence field of Colorado. The fracturing of other rocks, such as limestone and sandstone, affords favorable conditions for the accumulation of oil; but sandstone and, under certain conditions, limestone are capable of storing oil without fracturing, the fracturing merely increasing their capacity. Ficurp 7.—Diagram showing depth to which phosphate deposits are classified under article A of the regulations. PROGRESS IN CLASSIFICATION. Classifications of the phosphate lands that have been examined are made according to articles A and D of the regulations. Recent field work in the closely folded phosphate region in the Western States and in the comparatively shallow deposits of Florida has shown that the attitude of the beds in these localities is such that it is not necessary to make use of articles B and C in classifying the lands. The classifications that are made according to the regula- 132 CLASSIFICATION OF THE PUBLIC LANDS. tions outlined in article D are comparatively simple, but those made under article A are much more complex and require consider- able computation. In order to reduce to a minimum the computa- tions involved in determining the maximum depth a given phos- phate bed of known thickness and content of tricalcium phosphate may attain for the land to be classified as phosphate land, the ac- companying diagram (fig. 7) has been constructed, by which each individual problem falling under artiele A can be readily solved. All beds 6 feet or more in thickness are computed as 6-foot beds, and all beds having a content of tricalcium phosphate greater than 70 per cent are computed as 70 per cent beds. In order to determine from the diagram to what depth any phosphate bed whose thickness and content of tricalcium phosphate are known should be considered workable, the vertical line in the diagram that represents the thick- ness of the bed is selected and followed to its intersection with the diagonal line representing the percentage of tricalcium phosphate the bed contains. From this point of intersection the actual or constructed diagonal line is followed to the top of the diagram, where the maxi- mum depth limit is given. Every 40-acre tract between the outcrop of the phosphate bed and the line where the bed reaches this depth limit should be classified as phosphate land. s Where the phosphate rock occurs in several thin beds or groups of beds sufficiently close together to be mined as a unit but with dif- ferent percentages of phosphoric acid, all the material that can be mined as one bed should be taken, or in case part of it consists of barren rock that portion of the group that can be mined as a unit and will give the greatest amount of phosphate rock should be con- sidered. Where more than one bed exists that can be mined sepa- "rately without destroying the value of the other beds the land should be classified on the basis of each bed separately, all the lands being classified as phosphate land that can be so classified with reference to any one of the beds. This method of calculation gives the maximum amount of phosphate that can be obtained from the bed or group of beds and is the method used in determining what lands should be classified as phosphate land. As a result of action of this type, based on field examinations made by the geologists of the geologic branch, withdrawals and restora- tions have been recommended from time to time. Examples of withdrawal and restoration orders are given below: DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, January 25, 1918. The honorable the SrcreTaRy oF THE INTERIOR. Sir: Investigations by the Geological Survey in the Florida phosphate region indicate that the lands listed below lie within the phosphate area and prob- PHOSPHATE LANDS. 133 ably contain valuable deposits of phosphate. These lands were reported by the General Land Office in a letter, dated Janvary 15, 1913, as vacant Govern- ment lands, or as unapproved State or railroad selections. Their withdrawal is in accordance with the procedure outlined and advocated in my letter of August 16, 1912. I therefore recommend the submission to the President of the following order of withdrawal, involving 75,851 acres. Very respectfully, Gro. OTIS SMITH, Director. Fresruary 3, 1913. Respectfully referred to the President with favorable recommendation. WALTER L. FISHER, Secretary. ORDER OF WITHDRAWAL. Phosphate reserve No. 16—Florida No. 5. Under and pursuant to the provisions of the act of Congress approved June 25, 1910 (386 Stat., 847), entitled “An act to authorize the President of the United States to make withdrawals of public lands in certain cases,” as amended by act of Congress approved August 24, 1912 (Public No. 316), it is hereby ordered that the following described lands be, and the same are hereby, withdrawn from settlement. location, sale, or entry and reserved for public use. Tallahassee mcridian. T.2N., R.1 E, sec. 6, E. $ of SW. }. [Here follows the remainder of the land description.] Wo. H. Tart, Fesrvuary 8, 1918. President. DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, August 8, 1912. The honorable the SECRETARY OF THE INTERIOR. Sir: Field investigation by the Geological Survey indicates that the lands listed below do not contain deposits of phosphate. The following order of restoration, which involves 67,557 acres, is therefore recommended for sub- mission to the President for appropriate action. Part of these lands are within coal withdrawals, but none are included in national forests, power-site or petroleum reserves. Very respectfully, Geo. OTIS SMITH, Director. Avucust 17, 1912. Respectfully referred to the President with favorable recommendation. WaLter L. FISHER, Secretary. 134 CLASSIFICATION OF THE PUBLIC LANDS. s ORDER OF RESTORATION. Phosphate restoration No. 6—Wyoming No. 2. So much of the order of withdrawal made heretofore for classification and in aid of legislation affecting the use and disposition of phosphate lands, namely, reserve No. 4, as affects the lands hereinafter described is hereby revoked, for the reason that the Director of the Geological Survey reports that the lands are not valuable for the purpose for which withdrawn. And it is further ordered that all such lands not otherwise reserved or withdrawn are hereby restored to the public domain and shall become subject - to disposition under the laws applicable thereto upon such date and after such notice as may be determined upon by the Secretary of the Interior. Siath principal meridian. T. 23 N., R. 119 W., secs. 5 to 7, inclusive; sec. 18, all; sec. 19, all; sec. 30, all; sec. 31, all. [Here follows the remainder of the land description. ] Wo. H. Tart, Avucust 17, 1912. President. - As a result of these orders, 3,291,527 acres of lands were included in phosphate reserves on January 1, 1913. The areas involved in these recommendations are indicated in the following table: Phosphate land withdrawn, restored, and outstanding on January 1, 1913. . Outstand- State. Tanai aie) Heer | png ith — ‘ drawals. Acres. Acres. Acres. 45,979 2,199 43,780 2,215,834 | 1,157,778 | 1,058,056 274,962 sc nencwcacae 274, 861 581, 039 473, 294 107, 745 3,060,098 | 1,253,013 | 1,807,085 6,177,811 | 2,886,284 3,291,527 LANDS BEARING POTASH AND RELATED SALINES. GEOLOGIC OCCURRENCE OF THE DEPOSITS. No potash deposits of proved commercial value are yet known in the United States. Indeed, large deposits of potash salts are rare anywhere. Much the greater part of the world’s supply is obtained from deposits in central Germany, first known from their discovery near Stassfurt. The only other noteworthy deposit in the world is said to be that at Kalusz, Galicia, in northern Austria. Deposits of the Stassfurt type may eventually be found in the United States, but LANDS BEARING POTASH AND RELATED SALINES. 135 the chances are-perhaps greater that potassium-rich saline deposits in this country will vary widely from the German type in the character of the salts and in their mutual associations. It appears, therefore, that a discussion of the geologic occurrence of potash based on the Stassfurt type alone would be inadequate if intended to apply to possible deposits in the United States. Potash in its soluble or most useful forms is almost universally associated with other soluble salts. Therefore it is to the natural saline residues and natural or artificial brines and bitterns that atten. tion is directed in an exploration for soluble potash. Great deposits of salines, especially those composed of sodium chloride or common salt, occur in many parts of the United States, but so far as known none of the important deposits now worked for salt contain an important percentage of potash salts. Saline beds occur at the surface in the arid regions of the West more abundantly than elsewhere. These occurrences include at least two types of de- posits—the bedded salines included in stratified formations, which have commonly been tilted and otherwise displaced since their depo- sition, and the more recent saline deposits, which are to be found in the undrained playas and salt marshes.of the Great Basin region. The manner of formation of these more recent saline deposits is clearly revealed by the geologic record of the events that led to their accumulation and deposition. These events are so recent that the changes which are constantly taking place on the earth’s surface have - not yet obliterated or seriously obscured the evidence. This clearness and completeness of the geologic record justifies confidence in the correctness of the hypotheses concerning the manner of origin of saline deposits of this form. Saline deposits in the Great Basin region, as elsewhere, are formed by the accumulation of the water-soluble constituents of the surface rocks of the earth’s crust set free by that form of dissolution gen- erally referred to as weathering. These salts thus freed are taken into solution by the rainfall and the ground waters and are gradu- ally removed by the streams from the soils where they originate. Where these streams flow into inclosed basins with no outlet to the ocean, as is the rule in the Great Basin region, the dissolved salts are carried to the lowest part of the drainage area, where they ac- cumulate. In the past, presumably because of greater pre- cipitation than at present, these waters formed large lakes, which have since wholly or in part disappeared, and in the evaporation of these lake waters the salts have been deposited. Examples of saline deposits that have originated in this way in the low parts or so-called sinks of the inclosed drainage areas are common. . Saline deposits derived from the wash of continental areas nor- mally contain among other constituents a certain proportion of 1386 CLASSIFICATION OF THE PUBLIC LANDS. potash salts. As a whole, the quantity of potash associated with the sodium and other bases is so small—only 2 or 8 per cent of the whole—that the potash can not be recovered profitably for commer- cial use. However, as the potassium salts are somewhat more solu- ble than most of the other constituents of natural saline solutions, it is believed that they are generally among the last to be deposited when those solutions are evaporated. Owing to this selective action of evaporation it is probable that somewhere in the saline residues of completely desiccated lakes the potassium compounds will be segre- gated in much richer concentrations than elsewhere. This condition might not exist in natural saline deposits if the deposition of the salines were interrupted by some event which permitted the escape of the residual brines before all their constituents or final products were deposited. But apparently in the playas of the Great Basin no such event has interposed; hence all the constituents of the accumulated brines must still remain, and it is believed that in certain favorable places rich potassium-bearing salts exist. Most of the lakes that formerly existed in the Great Basin have completely disappeared by evaporation. Vast quantities of saline residues must have been deposited by the final drying up of these lakes, but for the most part such deposits are not now seen at the surface. It is believed that the greater part of the salines deposited simultaneously with the disappearance of the lakes has since been buried by sediments carried into these basins by streams and depos- ited as alluvial wash or in later lakes that have occupied the original depressions. Older saline deposits elsewhere have been formed in a similar way. If this hypothesis is sound, it follows that the probability of en- countering saline deposits by drilling in the bottom of the desiccated lake basins is very great and that under favorable conditions potas- sium-rich salines will be among those encountered. It is hoped that such buried salines may not in all places be so deep as to be inaccessible. Field work undertaken by the Government in the search for pot- ash has heretofore been largely of an exploratory character and has not followed any general or established rule of procedure. A sys- tematic study of brines, bitterns, and rock-salt deposit in all parts of the United States is included in the general plan. The Geological Survey has drilled a well approximately 1,000 feet deep near the center of the Carson Desert, in northern Nevada. This test is not regarded as completed. Elsewhere in Nevada and in California a number of shallow drill holes have been sunk in other ancient lake basins. Some of these experiments are yielding Se and possibly important results, LANDS BEARING POTASH AND RELATED SALINES. 137 CLASSIFICATION OF POTASH-BEARING LANDS. Congress, responding to the urgent recommendation of the Presi- dent, has so amended the withdrawal act (p. 48) that deposits of potassium-rich minerals may be included in reserves until an appro- priate law for their disposition is enacted. In view of the variety of such deposits in commercially available form and of their impor- tance in industry, it is doubtless the intention of Congress, if the present search is successful, to make appropriate provision for their development and disposal. Meanwhile, as investigation by the scientists of the Government bureaus reveals promising localities, these localities, if they involve public lands, will be withdrawn from entry until their value as sources of potash can be demonstrated or disproved. If they prove to contain rich deposits the withdrawals will be maintained until Congress can act. Three reserves of this type have already been created by the President. They include 133,829 acres in Nevada and California. The order of withdrawal by which potash reserve No. 2 was created is given herewith as an example of this type of action. DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, February 20, 1913. The honorable the SECRETARY OF THE INTERIOR. Sir: Investigations by the Geological Survey in the State of California indi- cate that the lands listed below, which lie within a dry lake known as Searles Lake, probably contain valuable deposits of potash. I therefore recommend the submission to the President of the following order of withdrawal, which involves 69,840 acres. Very respectfully, Gro. OTIs SMITH, Director. Fesruary 20, 1913. Respectfully referred to the President with favorable recommendation. WALTER L. FISHER, Secretary. ORDER OF WITHDRAWAL, Potash reserve No. 2—California No. 1. Under and pursuant to the provisions of the act of Congress approved June 25, 1910 (36 Stat., 847), entitled “An act to authorize the President of the United States to make withdrawals of public lands in certain cases,” as amended by act of Congress approved August 24, 1912 (Public No. 316), it is hereby ordered that the following described lands be, and the same are hereby, withdrawn from settlement, location, sale, or entry and reserved for classifica- tion and in aid of legislation affecting nonmetalliferous mineral deposits: Mount Diablo meridian, California. T. 24S., R. 48 E., sec. 32, SE. + of SE 4; sec. 33, S. $; sec. 34, SW. 3, W. 4 of SE. 4, SE. ¢ of SE. 4; sec. 35, S. 4 of SW. f. - 188 CLASSIFICATION OF THE PUBLIC LANDS. An area bounded as follows: Beginning at the southeast corner of sec. 31, T. 24S. R. 43 E.; thence west 2 miles; thence south 12 miles; thence east 9 miles; thence north 12 miles; thence west 24 miles, more or less, to the south quarter corner of sec. 36, T. 24 S., R. 43 E.; thence west 44 miles, more or less, along the south line of T. 24 8., R. 43 E., to point of beginning. This withdrawal is made subject to all rights lawfully initiated under any yalid mining locations made upon said lands so long as such rights are main- tained in full compliance with law. Wo. H. Tart, FEBRUARY 21, 1913. President. As the geologic conditions under which potassium deposits are formed differ from those required for the deposition of the other nonmetalliferous minerals, except the related salines, special field methods have been used for their discovery. The steps to be taken in classifying lands as potash-bearing or potash-free subsequent to field examination are, however, identical with those followed in the classi- fication of lands with regard to such other resources as phosphate and petroleum. The present laws do not provide for appraisal and sale, as in the case of coal lands, nor for lease. MISCELLANEOUS NONMETALLIFEROUS MINERAL LANDS. Some of the important minerals besides those already discussed are limestone, building and ornamental stones, cement materials, slates, glass sand, gravel, volcanic ash, diatomaceous earth, kaolin and other clays, fuller’s earth, gypsum, borax, salt, sulphur, monazite, talc, soapstone, quartz, feldspar, cryolite, mica, gems and precious stones, strontium compounds, fluorspar, barytes, pyrite, graphite, asbestos, magnesite, abrasives, asphalt and other hydrocarbons such as gilsonite and ozokerite, mineral waters, mineral paints, and bro- mine, as well as guano and peat. A great many of the so-called nonmetalliferous minerals contain metallic elements which either can not be extracted commercially or are regarded as of little or no value as metals but which by their union with nonmetallic elements from substances that are sought because of their nonmetallic properties. This is true of such minerals as corundum, an oxide of the metal aluminum, and gypsum, a sul- phate of the metal calcium. Monazite is sought as the chief source of oxides of several rare metals. There are, however, so-called non- metalliferous minerals whose metallic content is high and which may under certain conditions be regarded also as metallic minerals. A notable example is pyrite, a sulphide of iron, which is extensively employed in the manufacture of sulphuric acid because of its high content of sulphur. With advancement in industrial chemistry some minerals now classed as nonmetalliferous may be placed in the cate- gory of those which yield valuable metals and others now used may be discarded. MISCELLANEOUS NONMETALLIFEROUS MINERAL LANDS. 139 The geologic occurrence of the minerals named in the foregoing list is very diverse and the characteristics of the deposits containing them will therefore be referred to but briefly. Many of them exist in stratified or bedded form. Limestone, building stones, some cement materials, and some ornamental stones occur as sedimentary or metamorphic rocks. Slates are obtained usually from beds and are quarried in much the same manner as other building stone. Some glass sand is made by crushing a loosely consolidated sandstone or is obtained from beds of loose sand. Gravel is usually found in more or less bedded form in so-called “ gravel banks.” Volcanic ash and diatomaceous earth are ordinarily found in stratified deposits or beds. Clays, including kaolin and fuller’s earth, result from the accumulation of the less soluble residues of the decomposition of pre- existing rocks and minerals and are obtained almost entirely from bedded deposits. Some clays are obtained by dredging the bottoms of streams or lakes. Kaolin in its purest form results from the resid- ual decomposition of pegmatitic feldspar in place. Gypsum, borax, and halite, or common salt, are found in deposits that are related with respect to the manner of their geologic occur- rence. They are found most abundantly in association with stratified rocks and are regarded as chemical deposits resulting from the evapo- ration of waters of inland seas and lakes. Some deposits of borax and halite occur in more or less stratified form in the beds of present- day salt lakes or marshes. Sulphur deposits large enough-to be of economic importance occur as products of volcanic activity and are found near volcanic craters and also near some hot springs, either active or extinct. Monazite, owing to its minute crystalline form and great weight, occurs in greatest quantity where it has been concentrated in placer deposits. Talc and soapstone are very soft minerals which have presumably resulted from the alteration of other minerals. “Soapstone, a talc schist, occurs with other rocks of various kinds, usually crystalline or metamorphic; tale occurs in beds intercalated in schistose limestone and in lenses or pockets in certain intrusive rocks. Many minerals exist in veins or in the form of lode deposits. Quartz, feldspar, cryolite, mica, and some gems are found in veins in crystalline rocks. The strontium minerals occur principally in lenses, in granular and columnar masses, in bedded deposits, and in crystals that form nests and geodes in limestone. Fluorspar is found, as a rule, in veins in limestone, gneiss, schist, and sandstone. It is a common gangue of metallic ores, particularly those of lead, zine, and tin. Barytes occurs in veins and beds associated with other ores, as well as in veins and masses in limestone. 140 CLASSIFICATION OF THE PUBLIC LANDS. Pyrite is found in fissure veins and along the bedding planes of sedimentary and metamorphic rocks. It occurs in various other forms in rocks of practically all kinds and ages. Graphite is found mainly in the older crystalline metamorphic rocks in embedded masses and veins, although in some places it occurs in beds. Asbestos is an alteration product found in veins in older crystal- line rocks. Magnesite is also generally regarded as an alteration product and is found in veins as well as in bedlike masses. Some abrasives, like corundum, emery, and garnet, occur in small crystals, principally in veins in igneous and metamorphic rocks. Some asphalt impregnates sands, sandstones, and limestones and occurs in veins in these rocks. Other hydrocarbons, such as gilsonite and ozokerite, are found in veins or fissures, usually in sandstones. Mineral waters are, of course, obtained from springs; and some common salt and sulphur, as well as the materials of some mineral paints, are obtained from deposits formed by the evaporation of spring water. Bromine is found in natural brines and bitterns. Guano occurs in massive deposits, which in some regions are of considerable thickness. It is usually found in caves or other pro- tected places. Peat results from the accumulation in bogs of plant remains that have undergone slight modification at the top, although if the deposit is thick its lower portion may have been reduced to a mass somewhat resembling lignite. Sections 2320 to 2325, inclusive, of the Revised Statutes prescribe certain rules and regulations to govern the location and patenting of “mining claims upon veins or lodes of quartz or other rock in place bearing gold, silver, cinnabar, lead, tin, copper, or other valuable deposits.” Section 2329 provides for “claims usually called ‘ placers,’ including all forms of deposit, excepting veins of quartz or other rock in place.” Thus, although the minerals in the foregoing list exist in nature in beds, in veins, in massive form, or as liquids, or even in more than one of these forms, the law divides them into only two great classes—those which occur in veins or lodes of quartz or other rock in place and those usually called placers, including all other forms of deposits. The distinctions as to mode of occurrence of these minerals in nature are considered in classifying as mineral or nonmineral the lands containing them; such distinctions are the primary factors that under the present mining laws must always be considered in determining the law under which the deposits may be acquired. A large part of the information heretofore obtained by the Geolog- ical Survey regarding these minerals has been gathered in reconnais- sance examinations and in connection with reports on mineral re- sources, with the result that in most of the areas examined much geologic information that would be necessary for land classification MISCELLANEOUS NONMETALLIFEROUS MINERAL LANDS. 141 has not been obtained, although the data gathered are entirely ade- quate for the purposes for which they have been sought. No particular method is at present followed in the field examina- tion of deposits of these minerals, and there is no necessity for methods materially different from those pursued in detailed work on other metalliferous or nonmetalliferous deposits. Nor do the requirements as to the data to be gathered and the form in which they should be assembled differ essentially from those for other minerals. In addition to the location, a brief description of the nature and geo- logic structure of the rocks in which the deposits occur, with data regarding the thickness and succession of the rocks, their dip and strike, the extent of the deposits, and analyses of the material, are all important in the examination of bedded deposits. In the consid- eration of vein deposits data regarding the character of the vein, the systems and directions of joints, fissures, and fractures which may lave formed the ore cavities, the dip and strike of the veins, the nature of the gangue material, and the wall rock are equally im- portant. Statements of production are always desirable. The ques- tion of relative value—that is, of mineral value as compared with agricultural, power, or other values—must be considered in the classi- fication of some lands because of the fact that the laws governing the disposition of certain minerals refer specifically to lands that are “ chiefly valuable” therefor. Other factors, some or all of which are in many cases to be considered in judging the relative value of a mineral deposit, are the following: 1. Demand for the mineral, both present and future. 2. Character of the deposit; chemical and physical properties and extent. 8. Location with reference to market and in some cases to fuel supply. 4, Transportation facilities and rates. 5. Market price of the product. 6. Whether or not the particular deposit possesses other peculiar advantages rendering it more valuable than like depesits in the region and elsewhere. The character of the deposits, their location, and the transporta- tion facilities influence the cost of production by their effect on the cost of working the deposits, the cost of the plant, and in some places the cost of the fuel used in the manufacture of the product. These factors may also exert a most important influence on the sell- ing price of the output by their effect on the cost of placing it in the market. If the earlier geologic examinations had been made with a view to classification more precise instrumental work and a record of all the factors outlined as having a bearing on the deposits would have been required. No attempt has yet been made to systemize for purposes of land classification the available data regarding these minerals, and although the Geological Survey has prepared and sub- 142 CLASSIFICATION OF THE PUBLIC LANDS. mitted to the General Land Office many reports that have been a guide to action by that office and have been equivalent in many cases to nonmineral classification and in a few cases to mineral classification, no withdrawals and no formal classifications of lands because of their content of any of these minerals have been made. Although such minerals are useful and valuable, they are not in general of so great present or prospective use or value as coal and certain other nonmetalliferous minerals contained in lands for whose classification more specific provision has been made. Practically all minerals are of some value, but those of greatest value are naturally those which have the greatest present or future use and which are at the same time most easily or profitably marketable. Sand, for example, is of great use, but it is so common that in most localities it has almost no market value. Therefore, although the lands con- taining the nonmetalliferous minerals here discussed are, at the dis- cretion of the President, subject to withdrawal and classification under the act of June 25, 1910, as amended by the act of August 24, 1912, there is no sch public need for segregating these lands as there is for segregating lands containing deposits of such min- erals as coal, oil, potash, and phosphate. Nevertheless, should it be deemed by the President to be in the public interest to withdraw or to classify as mineral land an area containing any of these deposits, because of a public need for a present or a future reserve supply, or with a view to preventing alienation of the mineral ‘deposits under laws relating to nonmineral land, or as an aid to future disposition, his action would be based on a question of fact which it is the prov- ince of the Geological Survey to determine. So long as such with- drawal or classification is not deemed to be in the public interest, however, the land will remain open to exploration, discovery, oceu- pation, and purchase under the mining laws unless Congress shall otherwise provide. METALLIFEROUS MINERAL LANDS. PURPOSE OF CLASSIFICATION. The usual object in view in a consideration of the classification of nonmetalliferous lands as mineral land is to obtain their temporary withdrawal from entry, either to permit their appraisal, as in the case of coal land, or to await protective legislation, as in the case of potash or phosphate land. But metalliferous lands, as such, are not subject to withdrawal, and their classification is directed to other objects, which will be indicated by a brief account of some cases that have been considered by the Geological Survey. METALLIFEROUS MINERAL LANDS. 143 Perhaps the most important case yet considered is that relating to the Northern Pacific land grant. Every alternate section in a strip extending 40 miles on each side of the right of way was granted to the Northern Pacific Railroad Co. to assist it in constructing a trans- continental line, but the act provided that the railroad company should not receive any lands that were valuable by reason of their content of mineral deposits other than coal and iron. It therefore became necessary to classify the entire grant with respect to its value for such deposits, and in practice the chief problem of this classification has been to determine the presence or absence of valu- able metalliferous deposits. A great part of this classification was accomplished by specially appointed commissioners, and the Geo- logical Survey had no part in the work until 1905. Jn that year a Survey geologist, accompanied by a field agent of the Land Office, examined a large portion of the grant lying in Idaho and Montana in order to obtain information supplementary to that on which the special commissioners had recommended a mineral classification of the greater part of this tract. The Survey, however, took no further action regarding that particular examination. The greater part of the tract was classified as mineral land as the result of a hearing before the register and receiver at Coeur d’Alene, Idaho, but this classification was set aside by the Commissioner of the General Land Office on petition of the Northern Pacific Railway, on the ground that it was based on insufficient field work. In 1910, therefore, an appropriation was made by Congress (act of June 25, 1910; 36 Stat., 708, 739) for a new and much more thorough examination, for mak- ing which the Commissioner of the General Land Office requested the services of members of the Geological Survey. Four parties, each comprising a geologist, a geologic assistant, and the necessary camp hands, devoted the field season of 1910 to the work, which was completed in the season of 1911 by three similar parties. The result- ing classification, however, was not sufficient to decide the status of all the lands in controversy. The railway company had the right to contest classifications adverse to its interests and exercised this right as to many of the lands which, because they were classified as min- eral, would be excluded from the railroad grant. Hearings on the contested classifications are held before the registers and receivers of the appropriate land districts. An appeal can be taken from the decision of these officers to the Commissioner, and from him to the Secretary. No final decision has yet (February 28, 1913) been ren- dered concerning any of the classifications of the Survey that are under contest. The Survey has also been required to classify several Indian reservations, in whole or in part, either before or after the reserva- tions were opened to settlement, the question in the one case being 144 CLASSIFICATION OF THE PUBLIC LANDS. whether or not the lands shall be allotted to the Indians, in the other what kind of entry or settlement on them shall be permitted. Lands valuable for minerals are withheld from allotment to In- dians, as they are from the Northern Pacific Railroad grant, although for Indian lands no exception of coal and iron is made. A Survey geologist was engaged during the summer of 1912 in classifying the Flathead Reservation in Montana for the purpose of determining the mineral character of certain lands and their availability for allot- ment to the Indians, and many other classifications, both of individ- ual allotments and of entire reservations, have been reported to the Indian Office. ; Before Indian lands are thrown open to settlement it is desirable to know what parts of them contain valuable mineral deposits, in order that these parts may not be alienated as agricultural land. Failure to classify the lands in advance of the opening of the reser- vations is likely to result in conflict between agricultural and mineral claimants. This has occurred, for example, in the northern part of the Colville Reservation, which was thrown open to prospectors in 1898 and to agricultural claimants later. Numerous protests made by mineral claimants in this region against the issuance of patents to agricultural claimants have aroused the bitter resentment of the ranchers, who have been prevented by these protests from getting final patents. An examination of these lands for the purpose of de- termining whether the mineral claims showed deposits sufficiently valuable to entitle the claimants to mineral patents or whether these claimants were acting in bad faith, as alleged by some of the ranch- ers, was accordingly made by a geologist of the Survey in the season of 1912; and during the same season the unallotted part of the Col- ville Reservation was examined for the purpose of settling conflicts between mineral claimants and Indian allottees and of classifying the remaining unallotted lands. «nother type of classification has arisen of late, in which the Sur- vey has been required to pass upon many and varied individual cases in which the propriety of granting patent to claimants was in doubt. It is sometimes suspected that attempt is being made to ob- tain valuable agricultural or timber land or strategic points for power development by the subterfuge of a mining claim on land where in reality no mineral deposit of substantial value has been found. On the other hand, there is sometimes danger lest a* valu- able lode or placer deposit be covered by some forni of nonmineral entry. If these cases are important the department may call upon the Survey for any information that it may possess concerning a certain tract, or it may even direct that a geologist be detailed to make a special examination. One case of this type, of interest as one of the earliest examples of land classification by the Geological METALLIFEROUS MINERAL LANDS, 145 Survey, was the determination of the nonmineral character of a “school section” on the edge of the city of Tacoma, Wash. This detailed examination was made in 1895 and resulted in the defeat of the mineral claimant, who had attempted to obtain under the placer law nonmineral land possessing large suburban value. As a result of the decision the title to this land passed to the State of Wash- ington, METHODS OF CLASSIFICATION. AGENCIES EMPLOYED. Classifications promulgated by the Survey are made by the metal- liferous section of the land-classification board and are based on data gathered by the field geologist: and by him presented to the section. Other geologists having special knowledge of the area or type of deposits under consideration may be called in, so that each classification represents the best scientific and technical judgment of the Survey. PROBLEMS INVOLVED. Each classification of metalliferous land involves one or both of the following problems: (1) Whether an alleged “discovery” of min- eral constitutes valid ground for issuing a mining patent; (2) whether certain lands are without value for their metalliferous minerals and may therefore be patented under the laws relating to nonmineral land. The first problem is typically presented where the propriety of issuing patent to a mineral claimant is in question; a typical example of the second problem is that presented by the Northern Pacific land grant. Evidently the first problem is the more concrete and the more readily solved. In order to determine the validity of a specific min- eral claim all that is necessary may be to find and identify the claim and to estimate the value of the lode by sampling. The most difficult cases, on the other hand, are probably those that involve the classifi- cation of large areas in which little prospecting has been done. In order to reach an intelligent conclusion in such a case evidence of many kinds must be obtained, the gathering and effective presentation of which may involve the making of a fairly complete topographic and geologic map, a task which only a geologist can effectively perform. In actual practice few cases present only one of the problems stated. Even if the main problem is the first one it is usually desirable that the examiner should learn something of the general geology of the district; and if, on the other hand, the main problem is the second the apparent value of particular claims is an important part of the evidence. It is not necessary or practicable, therefore, to separate 78894°—Bull. 5837—13——10 146 CLASSIFICATION OF THE PUBLIC LANDS. the two main groups of cases in the detailed account of field methods that follows, despite their clearly distinct legal status. In most of the cases considered nearly all the kinds of information to be enumer- ated are used to a greater or less extent, and a geologic map of some kind invariably forms a part of the record. The metalliferous deposits examined or looked for in most of the investigations preceding classification are veins, magmatic ore bodies, contact-metamorphic deposits, and bodies formed by replacement. In mining law these deposits are usually comprised in the term “ lodes,” and they may conveniently be so designated here. Some cases have to do with placer deposits, which are easier to examine and classify than lodes. PRELIMINARY PROCEDURE. As in the classification of nonmetalliferous lands and geologic field work in general, it is the duty of the geologist, before he takes the field, to gather information about the geology of the region to be examined and to provide himself with a base map. Other informa- tion that is especially desirable for work of this class relates to the lo- cation and status of the mining claims in the region. This is the only matter that requires further notice here, for the subject of base maps has been discussed elsewhere and the utility of geologic in- formation is self-evident. Plats and descriptions of patented mining claims are on file in the offices of the surveyors general of the several States and in the General Land Office at Washington. These show accurately the posi- tion of the claims with reference to land lines or location monuments. Provided with copies of these records, the examiner is able readily to find the patented claims. [Less complete and accurate descriptions of the unpatented claims are filed in the offices of county clerks with the first records of location and the affidavits on assessment work. FIELD WORE. LOCATION AND TOPOGRAPHY. The methods of location used in classification of this kind may be any of those described on pages 53-61. Some of the conditions of classifying metalliferous land, however, influence the selection of methods. The minute accuracy that characterizes much of the work on coal land is not often necessary in work on metalliferous deposits, and it is therefore feasible to use comparatively rough methods like that of the pacing traverse, which has been employed to a consider- able extent. Another influential fact is that metalliferous land is more likely than nonmetalliferous land to be situated in mountainous territory. This is not obvious at first glance, but as metalliferous METALLIFEROUS MINERAL LANDS. 147 deposits are most common where the geologic structure is complex, and as mountains are regions of upheaval and disturbance, the con- nection between topography and mineral wealth is real. The rugged- ness of the areas in which the greater part of the work of classifying metalliferous land is done precludes the use of some methods that are especially adapted to work in a flat country, such as that in which distance is measured by the paces of a horse. The plane table is much used in open country, and stadia traverses of roads or streams are sometimes made for purposes of control. INVESTIGATION OF PLACER DEPOSITS. Geologic relations.—Although theory is not so important in rela- tion to placer deposits as in relation to lodes, the physiographic his- tory of the region may afford some guidance in the search for valu- able placer ground, as the following considerations will show. The most important geologic principle relating to placers is that concentration sufficient to make a valuable deposit has usually been the result of long and perhaps repeated working over of the gravels by streams. Therefore, other things being equal, well-washed de- posits consisting in part of reworked older gravels would seem most likely to be rich in gold. Moraines, on the other hand, or glacio- fluviatile deposits close to the place of their origin are unlikely to contain gold in sufficient concentration to be extracted with profit. With respect to the distance of the gravels from their source, how- ever, a happy medium is favorable. Too great proximity is incon- sistent with efficient concentration, but the gold, except in extremely fine division, is not carried so far as the gravels, and too great remote- ness from the source is therefore also unfavorable. Gold-bearing placers are likely to show a definite relation to such areas of aurifer- cus bedrock as can be outlined; they are partly within those areas but extend beyond their borders as a sort of fringe. Testing.—Although a knowledge of the general geology and physi- ography of the region may be a guide in the search for placers, the classification of land as valuable placer ground is always supported by more direct evidence, for the reason that the extent and value of a placer deposit can be determined much more closely than those of a lode. The examiner is expected to pan the gravels of all important streams in the area classified in order to obtain evidence regarding their possible value as placers and, incidentally, evidence regarding the gold content of the bedrock from which the placers have been derived. Testimony of miners——Owing to their necessary limitations, the tests made by the examiner must be supplemented as fully as possible by the testimony of miners and prospectors. From these the ex- 148 CLASSIFICATION OF THE PUBLIC LANDS. aminer may learn the tenor of the gravels, the probable extent of the pay dirt, and whether mining has been profitable. This testimony may be taken under oath, if the examiner has power to administer it, and should be corroborated, so far as possible, by assay certificates and other evidence. A geologist is able also to criticize the testimony in the light of geologic facts and would perceive, for instance, that an assertion that morainal gravels had been worked with profit would be in especial need of corroboration. INVESTIGATION OF LODE DEPOSITS. Kinds of evidence available.—The evidence which must determine whether land is to be classified as mineral because of lode deposits may be subdivided as follows: (1) General geology; (2) occurrence of valuable minerals or gangue minerals; disseminated or in veins, found in outcrops or float; (3) prospects and mines; (4) assays; (5) history of the region. Evidence of the first two classes is especially important in regions that have not been thoroughly prospected. General geology.—Certain geologic conditions, such as fissuring of the rocks, are generally recognized as favorable to the deposition of ore bodies; others, such as lack of deformation and very young country rock, are unfavorable. But ore deposits are the result of a happy combination of several factors, and it may be difficult to con- sider these factors separately and determine their relative weight. Of two districts geologically similar, one may be rich and the other poor in ore deposits, because of some difference not readily perceived. The most general cause of such differences, perhaps, is the variation in what Chamberlin and Salisbury call the “ diffuse regional concen- tration” of the several metals, whether in sediments or magmas, which is presumably the cause of metallogenic provinces. Now, it is evident that geologic conditions, including obscure con- ditions that may be largely determinative, are more likely to be similar in neighboring than in widely separated areas. Neighboring districts are the more likely, for one thing, to be in the same metal- logenic province. Therefore, in judging whether a given geologic condition is favorable or not, the investigator should especially in- quire whether it seems to favor the deposition of ores in the vicinity of the area to be classified. For example, if ore bodies are known in one locality at the contact of a batholithic intrusion with a certain limestone formation, it is probable that they will be found at the contact of the same rocks in neighboring localities. This reasoning by analogy may form one of the arguments in sup- port of a mineral classification, but it can rarely be made the sole ground for such classification of a large area, which can hardly be successfully defended against a contest unless it is supported by some definite discoveries of mineral, made by prospectors or by the geolo- METALLIFEROUS MINERAL LANDS. 149 gist himself. In fact, such concrete occurrences of mineral are likely to have even more weight in a contest than strictly geologic evidence. It may pertinently be asked, then, what special qualification for gathering the evidence required is possessed by a geologist. compared with a prospector or any other intelligent observer. The geologist would perhaps have no special advantage if unlimited time were allowed for the examination. In fact, however, the time is limited, it may be all too strictly. It is impossible within the time allowed to explore every square foot of the area, and therefore obser- vation must be concentrated where deposits are most likely to be found. Now, in determining what places are best worth examination the geologist finds abundant practical use for his knowledge both of general and of local geology. His general knowledge teaches him that some geologic conditions are more favorable than others to the formation of valuable deposits, and he distributes his attention accord- ingly. He does not, for example, waste his time in looking for quartz veins in undisturbed rocks, knowing as he does that deformation and fissuring are necessary to the formation of veins. The special knowl- edge of the region which he may already have or which he is prepared by training to assimilate rapidly will enable him to recognize in the geologic environment of the ore deposits that have been found the details that are significant. If, for example, most of the known deposits of a district are the result of interaction between a limestone and an igneous intrusive, the geologist will presumably be quicker than a layman to recognize this fact and will explore with especial care the contacts between these rocks in areas near those which have proved productive. The geologist, in short, is better prepared than the layman to follow clues. The shorter the time allowed for the examination the more decided the advantage of the geologist over the man without geologic training. An exploration sufficiently thorough to discover even a large propor- tion of the valuable deposits in the region to be classified is rarely possible, and the value of many of the deposits found must be doubtful before they are thoroughly explored. It is correspondingly impor- tant, then, that the fullest and most reliable inferences be drawn from the data obtained in the field. The following paragraphs are intended to show what kind of geologic evidence the examiner seeks. Country rock.—The broadest generalizations that can be made regarding the influence of country rock, as indeed regarding other geologic factors, are of negative character. Itis safe to say that very young unaltered volcanic rocks or imperfectly consolidated sediments are unlikely to contain metalliferous lodes. Further than this, how- ever, the probable richness of a formation bears no direct relation to 150 CLASSIFICATION OF THE PUBLIC LANDS. its age, for valuable deposits are found in rocks of all ages, from the Tertiary to the most remote. In a particular district, however, the ores may show a preference for certain rocks. The favorable rocks may be those that contain minerals in a finely disseminated condition which may be valuable if they are anywhere sufficiently concentrated. Copper, for example, seems to be a constituent of some basic igneous rocks. Ready replace- ability, or the power of reacting vigorously with mineralizing solu- tions, may be the determining favorable factor; and where the typical deposits of a district are replacements or contact-metamorphic de- posits calcareous sediments are usually more favorable than others. Again, the presence of some constituent which acts as a precipitant may determine the concentration of a valuable mineral; organic mat- ter probably precipitates gold under some conditions, and carbona- ceous slates appear to be a common country rock of gold deposits. Finally, some purely physical feature may be determinative. The hard rocks of a district may be fissured to form breccias in which the ore-bearing solutions can circulate and deposit, while fissures in soft rocks would be clogged with impermeable gouge; and fissures which are large and persistent in massive rocks might ramify, on entering fissile rocks, into a multitude of small slips parallel to the bedding or cleavage. Intrusions and metamorphism.—Although the nature and degree of the relation between igneous intrusion and ore deposition are still moot points, it is an established fact that ore deposits are especially abundant in the vicinity of intrusive contacts. Apart from strati- form deposits—such, for example, as those of iron oxide—ore bodies so remote from intrusive rocks as the lead and zinc deposits of the Mississippi Basin are rather exceptional, though not so exceptional as to make absence of intrusives a sufficient ground for classification of land as nonmineral. The general similarity in the distribution of ore deposits and of igneous rocks is particularly notable in the Western States. The presence of igneous intrusions must therefore be considered favorable, in general, to the deposition of ores. Ore bodies related to intrusion are found both in the intrusive rock itself and in the surrounding sedimentary rocks. Those which are not contact-metamorphic deposits in the strict sense are not more likely to be at the immediate contact than at a considerable distance from it. The central portion of a very large batholith is likely to be barren, but the peripheral portion is commonly ore bearing, and all of the denuded portion of a small batholith or stock is likely to contain ore deposits, for none of it is far from the contact. Large dikes also form the country rock of many ore deposits. The ores are formed in the rocks cut by the intrusive, not only within but beyond the zone of contact metamorphism, METALLIFEROUS MINERAL LANDS. 151 Structure—The geologic structure of most mining districts is complex, and in regions of nearly horizontal unfaulted strata metal- liferous lodes are scarce. Deformation, by giving rise to fault fis- sures and openings along bedding planes, probably determines the location of most lodes and is therefore favorable, in general, to the deposition of metalliferous ores. Faulting is of greater importance in the formation of lodes than folding. Some faulting is doubtless a prerequisite to the formation of fissures transverse to the bedding, although fault fissures along which great displacement has been effected are not commonly filled with veins of commercial importance, for, inasmuch as they are likely to be choked with gouge and subject to repeated movement, they are less likely to be ore bearing than fissures along which the displacement has been slight or even imperceptible. Veins are accordingly looked for near and parallel to faults of large throw rather than along those faults themselves. That sort of faulting which gives rise to a rather coarse breccia is perhaps most favorable. At any rate, zones of brecciation afford the best clue for the tracing of small faults and are likely to be mineralized. They are therefore looked for and examined with especial care. Folding, as well as faulting, may give rise to openings in which ores may be deposited. Saddle reefs constitute the most common type of deposits in openings thus formed. Outcrops and float of lodes—Outcrops of lodes afford the most direct evidence of mineral value that can be observed in the field apart from actual development, and they are therefore located and described with as great care as is practicable. If the deposits are veins, the direction and degree of persistence are determined if pos- sible; this determination is particularly important if the classification must be close in the matter of location, but it is also important if in a neighboring region veins of a certain direction are known to be espe- cially rich. Size and composition are other features noted. Size affects, of course, the degree of value, but the mineral content is of more immediate interest to the examiner. In order to recognize lodes of probable value, the examiner endeav- ors to learn as much as possible concerning the appearance of the out- crops of lodes containing valuable minerals and familiarizes himself with the minerals likely to occur in the extremely oxidized portions of such lodes. Details regarding the surface indications along veins of proved importance in the region examined are sometimes obtained from prospectors and miners. The importance of these indications may be very great, for the minerals that make the lode valuable may not appear at the surface. More commonly than not the primary sulphides are represented at the surface by oxides or carbonates. The thoroughly weathered portion of a rich lode may even contain no 152 CLASSIFICATION OF THE PUBLIC LANDS. compounds of the valuable metals. This is especially likely to be true of copper deposits, whose upper portions are commonly trans- formed to rusty porous masses containing quartz, iron oxide, and other substances that resist the action of the weather. This material, which is known as iron capping or gossan, may contain small amounts of the bright blue and green copper carbonates, but on the other hand it may be wholly devoid of copper minerals. Many lodes that weather to a gossan and others that are composed largely of | easily weathered minerals do not project above the surface and are therefore likely to be overlooked. If a lode is about as hard as the country rock its outcrop is nearly level with the general surface, and the position of a lode composed of soft, easily weathered material may be marked by a trench instead of a ridge. Many veins, again, have no outcrop; they are covered with soil, and their position is indicated only by float. It is therefore evident that both careful observation and intelligent inference are required to find the lodes and judge whether or not they are likely to prove valuable. The proximity of lodes containing minerals in sufficient concentra- tion to be commercially valuable may be indicated by the presence of such minerals or of gangue minerals associated with them, dissemi- nated through the country rock or in the form of narrow stringers. Some minerals commonly so found are calcite, pyrite, siderite, and chalcopyrite. The more easily weathered minerals are likely to be represented by their oxidation products. Siderite, for example, is usually and pyrite commonly represented by pseudomorphs of hy- drated ferric oxide. Extensive rusty staining of the country rock therefore causes the examiner to look for more specific evidence of mineralization. Other characteristic alterations of the country rock, such as leaching, chloritization, and sericitization, commonly occur along the walls of lodes and are therefore useful as clues. Probably the great majority of prospectors’ discoveries are made by following float* to its source, and mineral classification likewise may rest in large measure upon the evidence afforded by float. Time will not always permit the tracing of float to its source, and the ex- aminer must then be content with inferences drawn from the char- acter and situation of the float as he finds it. In any case the first step is to consider how the float probably reached its actual position. It may have done so by either (1) hill creep, (2) water transporta- tion, or (8) ice transportation, or by a combination of any of these agencies. 1. Most float has been transported to its present position by hill creep, which is constantly active on every slope. Angular float, without marks of attrition, which does not lie in an actual or former stream 1This term is commonly applied by prospectors to all fragments of lode matter not in place, however transported ; it will be used in this sense here. METALLIFEROUS MINERAL LANDS. 1538 channel or in a glaciated area has presumably come to its place by hill creep, and its source should be looked for, after the method of pros- pectors, by following it straight uphill. Normally the parent lode will be found somewhere between-the point where the float was dis- covered and the top of the slope. If a search is impracticable the probable source may perhaps be inferred, on the same principle, within narrow limits, especially if a good topographic map is avail- able; the source may thus be assigned to a particular section or even to a smaller subdivision. Moreover, the probable source can often be judged within narrower limits than those set by the distance from the point of discovery and the top of the slope. The small fragments of vein quartz, mingled with soil, which may be found almost. any: where in a region of deformed rocks, are likely to have crept down- hill for a long distance; but large blocks of quartz thickly strewn over a small and fairly well defined area, especially an elongated area on a moderate slope, may reasonably be presumed to have come but a short distance from a vein. It is evidently necessary, then, to note fully, on the spot, the size and character of the float fragments as a help in judging the source; and their size may also roughly indi- cate the thickness of the parent lode. 2. Rounded fragments or bowlders of float, especially if in a stream channel in an unglaciated area, may be presumed to have been trans- ported by water. Float of this character is also frequently followed by prospectors up the streams and slopes to its source. This process is too slow and difficult to be employed often by the examiner. But stream-transported float may ordinarily be assumed to have origi- nated in the drainage basin where it is found, and scrutiny of the stream gravels may tell the examiner what to look for in a particular basin. 3. Float that has been transported by glaciers is subject. to much the same conditions as water-transported float. It is usually to be recognized by its association with moraines and glacial sculpture but may sometimes be confused with float of the other two kinds. It is less feasible to find its source by systematic tracing than to find that of other float, but where the glaciation is local the parent ledge is likely to be near by and well exposed. As placer deposits are really one form of float in the broadest sense, this may be the appropriate place to point out their value as indi- cating the auriferous character of the country rock of the drainage basin in which they are found. ; It may be remarked, finally, that exceptionally, owing to migration of divides or their transgression by glaciers, float is found outside of the drainage basin in which it originated. This is most likely to be true of old stream gravels. 154 CLASSIFICATION OF THE PUBLIC LANDS. Prospects and mines—An important part of the examining geolo- gist’s work is to note the location of all prospects and mines and to examine all of them, with the possible exception of those that are well known as producers. The most obviously useful data to be ob- tained from mining properties concern the value and visible quantity of the ore and the production if the property is producing. The examiner checks one against another his own observations, the infor- mation given by assay certificates and smelter returns, and the tes- timony of owners or mine officials, which may be in the form of an affidavit if it is thought desirable by an examiner who is empowered to administer an oath. The information gathered from a prospect or mine may do much more than indicate the mineral or nonmineral character of the claim on which it is located and that of a little land in its immediate vicinity. The most useful clues may be obtained in openings which permit comparison between the appearance of a lode underground and that of its outcrop. By making these comparisons the examiner is much aided in recognizing the outcrops of important lodes that have not been opened, and by study of the geologic environment of prospected deposits he may form an opinion as to where others are most likely to be found. Samples and assays——Ore samples and assays showing their value give the most concrete evidence and have great weight at public hear- ings. To obtain abundant samples and assays, therefore, is one of the examiner’s chief duties, and quantity of material is not more important than full information indicating its value as evidence. Samples collected by biased persons are taken only too often either from the best part of a lode or from the worst part, or even from the wall rocks; and the procuring of truly representative samples requires both judgment and honesty on the part of the examiner. Full records regarding the collection of the samples are indispens- able. Even after every precaution is taken in the matter of collect- ing and record there may be much room for inference, for the weath- ered, superficial portion of a lode, which alone may be accessible, is sure to differ in tenor from the unweathered portion from which the valuable metals are partly or chiefly to be won. Where ores of the base metals are concerned, values may sometimes be estimated by inspection closely enough to dispense with assays. Usually, how- ever, and especially if values in gold and silver are to be found, the classification of any large tract calls for many assays, and material to be assayed for precious metals must be collected with special pre- cautions. Each sample must be large enough to suffice for several assays, so that any result whose accuracy is doubted may be checked, and the material must be broken up and well mixed to insure its homogeneity before it is divided into portions. BY-PRODUCTS OF MINERAL-LAND CLASSIFICATION. 155 The Geological Survey does not make assays, not being provided with the proper equipment or a sufficient force. Its assay work is therefore done by custom assayers of established reputation. History of the region.—The question sometimes arises whether the mining possibilities of a region are fairly represented by the extent to which it is developed. Ifa region contains few prospects and no mines, or if many of its prospects have been abandoned, is it or is it not because valuable metalliferous deposits are really absent? Some light may be shed upon this problem by the history of the region. If the region has long been accessible and is known to have been well prospected, lack of development should have some weight against classification of land as mineral. It must be considered, on the other hand, whether local prejudice against some kind of country rock or gangue material may not have lessened the value of prospecting, or whether the region may not contain deposits of a kind that has not been looked for. Abandonment of prospects may not always indicate the worthless- ness of the lodes; it is sometimes due to the miner’s failure to recognize valuable ores. Many metal prospectors have little knowledge of the appearance of ores other than those of gold, silver, copper, and lead and do not always recognize the secondary ores of copper, lead, and zinc. For this reason the dumps of abandoned mines may reveal ores of rarer metals or others not formerly used or commonly searched for by prospectors. Mining methods and facilities often, of course, determine the suc- cess or failure of a mine, and it is proper to consider in every case whether abandonment may not have been caused by inefficient mining, crudity of methods, or difficulty of transportation. The transpor- tation problem may be largely disregarded, for if a region develops good metalliferous deposits transportation is pretty certain to be provided in time, but the presence or absence of roads and trails has an important bearing on the accessibility of the region, which in turn is a factor of prime importance in deciding whether the absence of prospecting indicates the absence of valuable deposits. BY-PRODUCTS OF MINERAL-LAND CLASSIFICATION. VALUE OF COLLATERAL INFORMATION OBTAINED. The process of classifying the public lands as to their mineral char- acter involves the gathering of a large amount of information which is not only essential to the classification but valuable for other rea- sons. Furthermore, the accuracy and completeness of field observa- tion necessary for classification afford an opportunity to record many facts which are entirely extraneous to the classification itself but 156 CLASSIFICATION OF THE PUBLIC LANDS. which may be now or at some later time of interest and value in other ways. These “ by-products” of the process of land classification are of many kinds. Some are of value to home seekers and the public at large, others directly concern engineers and mining men, and still others are of present interest chiefly to scientists. DATA OF DIRECT INTEREST TO THE PUBLIC AT LARGE. While all information obtainable concerning the public domain is of ulterior interest to the people, information relating to such matters as the surface features, water supply, and character of the soil of a piece of land may prove to be of vital importance to the present or prospective settler. It is not practicable for the Geological Survey to make an exhaustive study of these features, but in the work of classification a certain amount of such information is always recorded. Thus, a map, supplemented by a written description, of each town- ship examined for its mineral content is placed in the Survey files, showing in a rough way the agricultural character of the country. From these records it is possible to tell whether a section of land is suitable for dry farming or is adapted only to grazing, to obtain some idea of the number and size of the trees upon it, or to prepare a pre- liminary report as to its irrigability. The field men engaged in work relating to land classification also record the position and size of all springs and water holes which they may find. This information is of direct value to the settler, but it also has another more general use. The more valuable agricultural lands of the public domain are rapidly passing into private owner- ship under the various settlement laws. It is recognized that most of the lands remaining are chiefly valuable for grazing or other uses not dependent on tillage, although the present laws do not adequately provide for their acquisition for these other uses. Congress has already given consideration to this problem and will doubtless reach a solution of it within the next few years. One of the most important factors to be considered in arriving at that solution will be the rela- tion of the watering places to the range lands, for such lands can not be used without an accessible water supply. The accumulation of these data, therefore, in addition to being immediately useful to settlers and others, will be valuable in solving one of the public-land problems now confronting our lawmakers. _ In studying and mapping a coal or phosphate bed it is necessary also to observe rather closely the geologic structure or attitude of the inclosing rocks. In some areas structure may have no bearing on mineral-land classification and yet may be valuable in deter- mining the probability of obtaining a good well or of striking artesian water. The principles governing the flow of underground BY-PRODUCTS OF MINERAL-LAND CLASSIFICATION. 157 water, though not generally understood by the layman, are yet com- paratively simple, and a glance at the geologic map of a region may indicate at once the most favorable locality for sinking a well. As a minor illustration of the value of such information may be men- tioned the fact that one of the geologists of the Survey had occasion during the summer of 1912 to advise two newly arrived settlers in the ceded lands of the Crow Indian Reservation, Mont., to sink their wells on the east side of a ridge rather than on the west side, as they had intended, because of the simple geologic fact that the rocks dip slightly to the east and the water follows down the dip, as is proved by the numerous springs on the east side and the few on the west. Such information is, of course, only of local applica- tion, but as the western country becomes more thickly settled and questions relating to city water supply arise, information of this kind gathered for the primary purpose of land classification may prove to be of considerable value. Miscellaneous data of these types are utilized in various ways. Such of them as can with propriety be so used may be published in the bulletins in which the geologic material assembled in the course of land classification is made available for public use. Others, al- though not published and not used in mineral-land classification, are of the greatest value to the department in administering laws relating to nonmineral land, like the enlarged-homestead act, the desert-land law, or the Carey acts. Still others represent merely the accumulation of data likely to be needed if certain moot questions concerning public lands are to be decided by future legislation. All these actual or prospective uses, however, either directly or indirectly concern the public at large. DATA RELATING TO PROSPECTING AND MINING. Information regarding the character, location, and extent of each stratum of economic importance in the area examined forms a large part of the data on which classification is based. This information is published by the Survey in special bulletins or in the annual “ Contributions to economic geology.” A study of the map and _ of the plates of sections taken on the coal beds in any field, for ex- ample, will indicate to the prospective operator the most favorable location for a mine, and the text includes observations concerning the cover of the bed, the character of the roof and floor rocks, and the general structure, including faulting, of the inclosing strata. Aside from the local and particular facts recorded for each area, as this work progresses the extent and character of each of the great jnineral-bearing provinces are being accurately determined and more and more comprehensive and definite data concerning the mineral wealth available for the Nation’s use are being gathered. 158 CLASSIFICATION OF THE PUBLIC LANDS. The study of the rock structure in an area is valuable not only in relation to its water supply, as has been indicated, but also as bearing on the occurrence of oil. The accumulation of oil and gas in the strata is governed by laws which are probably akin to those which direct the movement of water, and a knowledge of the rock structure is therefore, as a rule, of great assistance in the location of an oil well. Some new oil fields have been prospected and opened almost entirely on geologic evidence of this kind. It has also hap- pened that the details of rock structure observed in a field examined merely for coal have been found to have an entirely new applica- tion and significance in subsequent prospecting for oil. In view of this close interrelation of geologic phenomena, therefore, the field geologist carefully records all the facts he observes in the course of his work, even though they appear to have no present bearing on the subject of land classification. SCIENTIFIC DATA. Data of interest at the present time chiefly to the scientist form another important “by-product ” of the process of land classifica- tion. It is difficult, however, to select any group of facts as being of strictly scientific value alone, for new discoveries may at any time enlarge their significance and impart to them an unexpected economic importance. Many facts are, moreover, of equal interest to the pure scientist and to the engineer or the layman, so that while a great amount of scientific information has been collected in the work of land classification during the last six years, the purely eccnomic value of much of it has already warranted the necessary expense. Many data concerning the areal extent of different geologic forma- tions have been gathered in the last few years and will be of use in connection with the geologic map of the United States which the Survey is now engaged in constructing. The stratigraphic relations of the formations, their composition, and their fossils constitute the only chronicle of conditions which have, at different times and divers places, existed on the earth. From this record some idea can be gained of the former geography of the country, of the great earth movements such as culminated in the formation of the Rocky Moun- tains, of the climatic conditions which formerly existed, and of the ancient plants and animals. These matters are at present chiefly of philosophic interest, but it has been by the accumulation of such facts in the past that science has been enabled to render valuable id to mining and other industries. Furthermore, information of this kind, while perhaps of little present interest to the average lay- man, is of vital importance to the teachers of science in the univer- sities of the country. Asa case in point may be mentioned the recent discovery, by a Survey geologist engaged in the classification of coal CLASSIFICATION IN RELATION TO WATER RESOURCES. 159 lands in New Mexico, of a great unconformity which separates into two formations a great thickness of strata that had hitherto been considered as a unit. This discovery is important not only on account of its strictly scientific bearing, but because it indicates that high- grade coking coal occurs in rocks of comparatively recent (Eocene) age. It therefore appears that much important and diversified informa- tion is obtained in this way. Science is continually garnering facts against the time when their economic importance will appear, or when they may be correlated with other facts to furnish a broad hypothesis which may profoundly affect methods of prospecting or developing some mineral, such as oil. In addition, much local infor- mation of direct and immediate value to the mine operator or pros- pector is so gathered. Finally, the best obtainable record of the topography, water resources, and soils of the area examined is officially made. While the classification of public land is the im- mediate object of the work described in this bulletin, it is evident that such work, because of its exacting requirements as to accuracy and thoroughness, furnishes the best possible basis for valuable scien- tific generalizations. CLASSIFICATION IN RELATION TO WATER RESOURCES. GENERAL PRINCIPLES OF WATER UTILIZATION. One of the most important factors in the development and use of the remaining public lands within the United States is water supply. The development of power, the extension of agriculture and grazing, the growth of mineral industries, transportation, and various other activities depend directly on the quantity and quality of the under- ground and surface waters in what is, generally speaking, an arid region. To dispose of or to administer the remaining public lands without reference to their water supply is to ignore that natural resource which will, perhaps more than any other, affect their future utilization. Water is unique among the mineral resources of the earth in that, within natural limits, its supply is continually replenished and is there- fore, in a large way, inexhaustible. That is to say, within the limits of the natural yield of a basin a certain minimum quantity of water will be available year after year in any river channel for irrigation, for city supply, or for power, as may be required. Aside from the inherent value of the water, the ownership of an important source of water supply becomes of the greatest consequence, for such owner- ship carries with it a measure of control, for an indefinite time, of all industries dependent on that varticular source. 160 CLASSIFICATION OF THE PUBLIC LANDS. Statutes and court decisions both recognize that water should be devoted to its highest use, and the laws of many States provide for the condemnation of an inferior use in the interest of a higher one. Such laws generally recognize a municipal or domestic use of water as the highest which may be made, because of its necessity in the sup- port of life. Next in order comes the use of water in agriculture for irrigation, whereby the available food supply is affected. The use of water for power, though important and valuable, is inferior to either municipal use or use for irrigation and may, in general, be con- demned if necessary to insure higher utilization. The greatest value of a source of water supply at any particular time will depend, how- ever, on the demands for domestic or municipal use, on the proximity of a tract of arable land adapted to agriculture, and on the quantity of power that may be developed and the availability of a market for it. Such value may change with the development of the country, making necessary the abandonment of established industries in order that the water may be available to supply a greater need. Changes in use will, however, follow the economic law, as the damage to estab- lished industries must be paid for, and to that extent the cost of the water for other use will be enhanced. Important conditions are inherent in the use of water for various purposes. Its use for power affects neither its quality nor its quan- tity, but its use for irrigation depletes its quantity and its municipal or domestic use not only depletes its quantity but impairs its quality. Various uses may he and in many places are compatible with one another. In other places the conflict in use may be only partial. Many of the most advantageous sites for developing power, which, un- der conditions of modern long-distance transmission, are not depend- ent on a near-by power market for their value, are located in the upper portions of river basins, where the slopes are steepest and where demands for other use are not likely to be made. Under such condi- tions the water may be utilized in a power plant or a series of power plants and still be available for other purposes by the sacrifice of only so much of the power head as may be necessary to obtain ade- quate pressure in the pipes of the city water mains or to maintain the elevation of canals required to cover irrigable lands. In similar manner water that, has been used for a municipal supply may still be available, as sewage, for a certain amount of irrigation. The equalization of the stream flow in order to insure a continuous output of power will in general increase the value of the stream for munici- pal use. The use of water for irrigation, on the other hand, is limited to the growing season and requires the concentration of flow in ac- cordance with the needs of crops during that season. The complete utilization for irrigation of a stream whose flow has been equalized for power will make necessary storage below the power plant of the CLASSIFICATION IN RELATION TO WATER RESOURCES. 161 flow of the nonirrigation season in order to render it available for the irrigation of crops in the following growing season. The practi- cability of such storage and redistribution of flow will depend on local topography and must be determined for each locality. The con- ditions which affect the present and future practicable utilization of water are therefore very complicated, and the classification of land as regards its water resources is correspondingly difficult. . In genera] the development and use of valuable power sites involves the construction of expensive systems for transmitting the power to distant markets and distributing it among small customers. A water- power development can be most fully utilized and therefore has its greatest value when connected into a system containing other hydro- electric or steam-power plants, because a large system will generally have relatively uniform power requirements on account of the varied use of the power and also a relatively flexible power output on ac- count of the steam plants and of the storage capacity which may be available in connection with some or all of the water-power plants. In view of these conditions the combination of power plants into big systems is natural and tends to more economical and more complete utilization of the power resources. As a duplication of such a power system in any territory is uneconomical and in general is impracti- cable, a monopoly of the power market results, and such monopoly, if subject to proper public control, should be encouraged. Monopolistic tendencies in the control of water resources entail difficulties and dan- gers that have been recognized by Congress, as manifested by the laws governing rights of way, especially for the purpose of develop- ing and transmitting power, on or across the public lands. The protection of the people against the possible bad effects of monopoly and the retention of control of the use of this important source of power, which may be expected to increase in value with the decrease in available fuels, is at present accomplished by the United States through ownership of the land which is required for the use of the water resources. Congress has provided no means for the alienation of power lands as such and has sanctioned their use for commercial purposes only under a limited permit revocable by the secretary of the department having jurisdiction. It provided for rights of way for power-transmission lines under the same law but by a later act has authorized a fixed tenure for a period not exceed- ing 50 years. CLASSIFICATION OF WATER-POWER SITES. PRELIMINARY WITHDRAWALS. The classification of lands as water-power sites and their reserva- ion under the acts authorizing withdrawals is in general first made in the absence of detailed examination to determine power value and 73894°—Bull, 587—13——11 162 CLASSIFICATION OF THE PUBLIC LANDS. is of a preliminary or tentative character. Examination in the field provides a satisfactory basis for final classification and adjustment of withdrawals. The following paragraphs relate more particularly to preliminary classification and withdrawal but describe also the routine procedure followed and records prepared in all withdrawals tor power-site purposes. The principal steps taken in connection with the making of power- site and reservoir withdrawals are as follows: 1. Initiation of search for possible power or reservoir sites. The possibility of the existence of valuable power resources is brought to the attention of those charged with the duty of recommending withdrawals through general probability that such sites may exist, through requests for report on the possibility of there being such sites, or through information as to the possible existence of such sites derived from reports of field employees of the Geological Survey or other offices, from news items, from newly published maps, from the filing of applications for rights of way, and from other sources. In general the initiative in the premises is taken by the Geological Survey, but it not infrequently occurs that some power company intending to make surveys for a hydro-electric development in new territory requests the withdrawal of the lands likely to be occupied. The purpose served by withdrawal of such lands is two- fold. The valuable power sites that might otherwise be alienated as nonmetalliferous claims, timber and stone entries, agricultural entries, or for some other purpose, are retained in public ownership, and the company or person eventually developing the resource, pre- sumably but by no means necessarily the one who requested the withdrawal, is protected from the intervention of other rights and has merely to acquire the necessary rights from the United States instead of from the United States and a host of persons who might otherwise have succeeded to ownership of the land. 2. Estimation of character and value of probable development and approximate description of the lands under consideration. This step involves an examination of existing data on stream flow and rainfall, as well as of maps, engineering reports, and all other available sources of information. In some cases information definite and conclusive in character may be brought to light. On the other hand, it fre- quently happens that estimates of stream flow must be based on nothing more reliable than conditions of run-off in basins many miles distant and that estimates of available head for power development must be derived from elevations at scattered points culled from rail- road folders and similar data of doubtful applicability. 3, Examination of status of lands and definite description of lands to be included in the order of withdrawal. The lands presumed to be valuable for power or reservoir sites are platted on township plats CLASSIFICATION IN RELATION TO WATER RESOURCES. 163 of the public survey or tracings of them, and the status of the lands as to ownership is ascertained by examination of the records of the General Land Office and indicated on the township plats or tracings. All patented lands are eliminated from further consideration. Lands which are covered by location or entry but title to which still remains in the United States are included in withdrawals to the end that the order of withdrawal may become effective if for any reason the lands do not proceed to patent. Such withdrawal in no way affects the rights of an entryman who proceeds with the acquisition of his claim in accordance with the law, but it immediately becomes operative in case the claim is abandoned or for any reason becomes invalid. Definite description of the surveyed lands to be withdrawn is made by legal subdivisions in conformity with the official survey. Unsur- veyed lands are described by townships and some lands in town- ships that are partly surveyed by sections, in accordance with the probable protraction of the public survey; also by distance from the stream or streams having value as a source of power, in some such phrase as “ all land within half a mile of Snake River.” All withdrawals are so made as to include the least area that will effectively protect the resources involved. Where data are meager or defective the withdrawals are at first necessarily of relatively great extent but are eventually reduced as more definite and reliable data are acquired. The area of the land to be withdrawn in each town- ship is compiled from the plats of the public survey, or estimated for unsurveyed lands, and the total area of the withdrawal is computed. 4, Preparation of order of withdrawal. The draft of a formal order of withdrawal is next prepared, together with a letter to the Secretary of the Interior transmitting the order and recommending its approval. On approval by the Secretary of the Interior orders of withdrawal are transmitted to the President for his consideration and become effective on his approval. The following order is typical of the present form of withdrawals under the acts of June 25, 1910 (36 Stat., 847), and August 24, 1912 (87 Stat., 497) : DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, October 12, 1912. The honorable the SECRETARY OF THE INTERIOR. Sir: In accordance with your general instruction, I recommend the with- drawal for water-power sites of the following areas, involving 240 acres. This order of withdrawal includes no lands covered by enlarged-homestead designa- tions. Very respectfully, Gro. OTIs SMITH, Director. OctoBEr 19, 1912. Respectfully referred to the President with favorable recommendation. SAMUEL ADAMS, Acting Secretary. 164 CLASSIFICATION OF THE PUBLIC LANDS. ORDER OF WITHDBAWAL. Power-Site Reserve No. 299. Mill Creek, California. Under and pursuant to the provisions of the act of Congress approved June 25, 1910 (86 Stat., 847), entitled “An act to authorize the President of the United States to make withdrawals of public lands in certain cases,” as amended by the act of Congress approved August 24, 1912 (37 Stat., 497), it is hereby ordered that the following described lands be, and the same are hereby, with- drawn from settlement, location, sale, or entry and reserved for water-power sites: Mount Diablo meridian. T. 26 N., R. 1 W., sec. 24, SE. } of SE. 4; sec. 26, SE. 3 of NE. 4, SW. 3 of NW. 4, NW. 3 of SW. 4; sec. 32, S. 3 of SW. 4. Wo. H. Tart, Octoser 18, 1912. President. Orders of withdrawal affecting lands within Indian reservations, made under sections 13 and 14 of the act of June 25, 1910 (36 Stat., 855, 858), are forwarded to the Secretary of the Interior through the Office of Indian Affairs. The following order illustrates the form in which such withdrawals are now made: DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, May 23, 1912. The honorable the SEcRETARY OF THE INTERIOR (through the Commissioner of Indian Affairs). Sime: In accordance with your general instructions, I recommend the with- drawal for water-power sites of the following areas, involving approximately 6,817 acres (in the Blackfeet Indian Reservation). Very respectfully, H. C. Rizer, Acting Director. JUNE 18, 1912. I concur in the above recommendation. R. G. VALENTINE, Commissioner of. Indian Affairs. OrpER oF WITHDRAWAL. Power-Site Reserve No. 275. St. Mary River Tributaries, Montana. It is hereby ordered that the following described lands, valuable for power sites, be, and the same are hereby, reserved from location, entry, sale, allot- ment, or other appropriation in accordance with the provisions of the act ap- proved June 25, 1910 (36 Stat., 855), and that no trust or fee-simple patent be issued as regards these lands until further orders: CLASSIFICATION IN RELATION TO WATER RESOURCES. 165 Montana meridian. [Description of lands.] SAMUEL ADAMS, JUNE 22, 1912. First Assistant Secretary. Withdrawals of this form receive the concurrence of the Commis- sioner of Indian Affairs before being forwarded to the Secretary of the Interior and become effective on approval by the Secretary, no action by the President being contemplated by the law. Copies of approved orders of withdrawal are furnished to the Geological Survey, to the Office of Indian Affairs if affecting Indian lands, and to the General Land Office, and notification thereof is sent to the local land office of each district in which the reserved lands are located. Notation of the withdrawal is thereupon made on the tract records of the General and local land offices. Thereafter entries inconsistent with the purpose of the withdrawal, except under the mining laws pertaining to metalliferous minerals, are rejected. Modi- fications of a withdrawal may, however, be made to permit the allow- ance of an application that will subserve the purpose of the with- drawal or that involves a more beneficial use of the land than could be had under the purpose of the withdrawal. Withdrawals therefore in no way interfere with the proper development of the resources involved but tend toward their most complete and_ beneficial utilization. 5. Preparation of minutes. At the time each order of withdrawal is prepared minutes are written setting forth the object sought to be attained by the withdrawal, the extent and value of the resources involved, the data on which the withdrawal is based, and other perti- nent facts. Orders of withdrawal are numbered consecutively in chronologic order, and successive withdrawals on any stream are also given consecutive numbers in connection with the stream name. The various sets of minutes for withdrawals on any stream therefore con- stitute a concise statement of its value for power or reservoir sites and of the data relating thereto. 6. Office records. When notice of the approval of an order of with- drawal is received at the Survey, the withdrawn area is plotted and numbered on a General Land Office State map. A township card is prepared for each township affected, showing the location of the stream and indicating the legal subdivisions withdrawn and the number of the withdrawal. If more than one withdrawal is made in a township, the card is prepared so as to show the withdrawals sepa- rately and constitutes a graphic record of all withdrawals and restora- tions of withdrawn lands. The numbers and dates of recommenda- tion and approval of all power-site withdrawals and restorations 166 CLASSIFICATION OF THE PUBLIC LANDS. involved are tabulated on the back of the card. The front of a typical township card is shown in figure 8. In a ledger kept for withdrawals and restorations are noted, when the order is prepared, the number and area of the withdrawal or restoration and the date of the recommendation of the Geological Survey. The date of approval is also noted in the ledger when the copy of the approved order is received. T.RS.withdrawal No.77 \P.S.re: P.S.reserve No.77 Ficurn 8.—Typical township card illustrating action taken by United States Geological Survey on power sites. The complete record of the Survey relating to a power-site with- drawal consists of the following items: (4) Order of withdrawal, filed by withdrawal number and therefore chrono- logically. (b) Minutes, filed by number of withdrawal and therefore chronologically. (c) Township plats showing status of lands as to ownership, filed in binders by number of withdrawal] and arranged by principal meridian, range, and township. ; CLASSIFICATION IN RELATION TO WATER RESOURCES. 167 (d@) Township cards showing the extent and date of withdrawals and restora- tions, filed by States and arranged by principal meridian, range, and township. (e) Mounted State map on Which withdrawals and restorations are platted. (f) Withdrawal ledger in which is kept a chronologic record of withdrawals and restorations showing the number, area, date of recommendation, and date of approval. : METHODS OF FIELD EXAMINATION, DIVERSITY OF CONDITIONS. The examination of lands and conditions along any stream for the purpose of locating a feasible power site is a fairly common and well-defined engineering operation. The examination of lands and conditions for the purpose of classifying the lands according to “power value,” as the expression is interpreted in this bulletin, is quite another matter. In the first case, the effort is made to locate one or more sites that appear best adapted for development under the prescribed conditions of cost and prospective market which prevail at that particular time. The study is concentrated on the lands that will be involved in that particular development. In the second case, all the lands in public ownership adjoining or near the stream are presented for consideration, and the problem is to deter- mine whether any or all of these lands could be used in the develop? ment of any feasible power site. Moreover, the feasibility can not be settled on the basis of present limitations of development but must be determined according to what are believed to be the limi- tations of a future day, when water power will be a more vital factor in our economy than it is now and when, by reason of increased demand, a development whose unit cost would now be too great would become thoroughly practicable. Power sites are classified according to their future possible utility as well as according to their present value. There are other features which still further broaden the scope of an investigation of the kind here described. It is necessary to de- termine whether the lands examined may not be more beneficially devoted to the use of water for domestic supply or for irrigation than for power, and whether their use for power may not be preju- dicial to the other uses at the site in question or at some other site more or less remote. It must also be determined in many cases whether the land itself, irrespective of any distant lands which may be served, is of more value for agriculture or as a town or manufacturing site than as a power site. Such a consideration applies especially to lands that may be suitable for storage reservoirs. Usually the civic, industrial, or rural improvements that have previously been made in a reservoir site largely control the decision on this point, but the cases in which such influences are absent are still relatively frequent. Therefore 168 CLASSIFICATION OF THE PUBLIC LANDS. the field of investigation again spreads beyond the actualities of the present and an estimate of prospective events must be made. ' Finally, it must not be forgotten that human activities are not confined to the utilization of water—that a community which pro- duces must, if its products are of value, have suitable means of transportation. Therefore it frequently occurs that consideration must be given to the.relative usefulness of a piece of land as a power site or as a right of way for a railroad. In some places the bottom of a canyon that is suitable for power development or a basin that is suitable for a reservoir is also an advantageous railroad route. Although it is usually possible to locate an alternate railroad route, the cost of utilizing it may be so great as to outweigh the advantages that may accrue from development of power along the stream. It is thus necessary to appraise the relative values and comparative costs and choose the course that is or is likely to become of the highest human benefit. The classification of lands for water-power sites therefore requires a broad perspective, and it comprehends the study of so many variable conditions and prospective changes in public demand that mistakes are easily made and mature consideration is always necessary. Field examination naturally falls into two classes. The first is recon- naissance, made in response to urgency. The second is final and de- tailed and involves all the precision of instrumental work and the careful deductions made possible thereby. RECONNAISSANCE EXAMINATION. A suitable report on a water-power site classification should cover as many of the subjects listed in the following syllabus as may be relevant: I. Sources of data used in report: 1. Personal examination—route followed and time consumed. 2. Water-supply papers. 3. Maps. 4. Reports of engineers. 5. Miscellaneous. II. General introductory description, including location as to State, rivers, cities, township, and range. III. Description of the power developments and possibilities on the river, showing by sketch on best available maps location of dams, power canals, and power houses already constructed and possible location of these essential features for other power developments. Ownership of plants already constructed and use made of the power. IV. Physical characteristics : 1. Topography at dam site. 2. Relation of tract to a possible power development described under III above. : 3. Head available, how secured, whether by dam or by dam and canal. 4. Character of dam sites, holding ground for canals, and site for power house, CLASSIFICATION IN RELATION TO WATER RESOURCES. 169 Vv. Water supply: 1. General description of drainage area. 2. Actual records if available, showing maximum, minimum, and mean discharge for each month, also absolute seven-day minimum for the year. 8. Storage already developed. 4. Storage possibilities: (a) Location of reservoir sites. (b) Height of dam. (ec) Capacity of reservoir. 5. Prior water rights above and below power site. 6. Ice conditions during winter months: (a) Without storage. (6) With storage. VI. Possible power development: 1. Horsepower at wheel shaft (without storage). 2. Horsepower at wheel shaft (with storage). VII. Cost of power development: 1. Cost of diversion or forebay dam. 2. Cost of canals. 3. Approximate cost of complete installation per horsepower devel- oped: (a) Without storage. (b) With storage. VIII. Market for power: 1. Present. 2. Future. 3. Length of transmission lines, ete. IX. Suggestions and recommendations: 1. Relative to lands withdrawn. 2. Relative to other public land which has or may have value for devel- opment or transmission of power. X. Appendixes: L Water-supply records. 2. Maps. 8. Pictures. Before entering upon field work the hydraulic engineer should collect all available topographic and hydrometric data relating to the stream under investigation. For many streams the topographic data may be obtained from the United States Geological Survey topographic sheets, the United States Land Office township plats, county and other maps, or railroad location surveys and profiles. Study should also be made of the precipitation records collected by the United States Weather Bureau and the river-discharge records made by the United States Geological Survey and by private citizens. After obtaining in advance as much information as may be available, the engineer proceeds to the field. His instrumental equipment usually consists of hand level, steel tape, aneroid barometer, com- pass with sight alidade, and camera. In some investigations it is nec- essary to carry a current meter. These instruments and the notes, maps, and other data procured in advance, together with a map or de- 170 CLASSIFICATION OF THE PUBLIC LANDS. scription of the locations of the public land along the stream valley, constitute the working equipment. The engineer travels by wagon, on horseback with pack outfit, by boat, or on foot, as the conditions may require, and his personal equipment is made appropriate to the conditions. The engineer, after examining all the lands in the stream valley and studying the relation of the critical features to the public lands, constructs what may be called a mental picture of the situation in its most productive condition of water-power development. He also works out the variations which might be made in his plan of de- velopment, knowing well that no other engineer covering the same ground independently would conceive the identical plan of develop- ment that he would. It is even necessary for the engineer to con- sider plans and possibilities that may appear to him impracticable or fantastic, for the serious proposal of such plans is a frequent occurrence in the routine experience of the department, and a rela- tively supérficial glance over the country gives evidence that many such plans have been put into effect. Especially is it necessary for the engineer to- gather local information concerning proposed de- velopments of all kinds and to obtain as many working details of such developments as may be possible. To this end it is frequently essential to follow up rumors of prospective development. Although most of these rumors may prove inconsequential, they now and then lead to information whose importance fully compensates for the time spent on rumors that have no basis in fact. If the engineer’s investigations show that the slope of a river along a certain section affords a working head which, in connection with the known or supposed flow of the stream, indicates the possi- bility of a power site, he determines in a rough way the method or methods by which that site may be utilized. It is unnecessary for him to make final location surveys, because the fact that the power site exists is usually sufficient for the purposes at hand. The particular method of development will eventually be determined largely by the state of the science at the time the development is to. be made. It is recognized that the details of location and-equipment depend on the progress attained at the time of construction. We know, for example, of many old developments which if constructed to-day would be of an entirely different type. a The standards of capacity which warrant the withdrawal of public lands for power sites vary with the location, and in many cases the decision rests largely on the abundance of power sites in the imme- diate region. A stretch of river having a fall of 10 feet to the mile may, in regions where power sites are not abundant, be worthy of withdrawal, whereas a similar stretch in a region abundantly sup- plied with sites of greater capacity may not be of sufficient im- CLASSIFICATION IN RELATION TO WATER RESOURCES. 171 portance for departmental action. The determination of the proper course is difficult, for the question of feasibility must be partly an- swered with regard to future conditions. All the factors discussed in the beginning of this section, such as domestic water supply, irri- gation, and transportation, must be borne in mind, and it is impera- tive that the engineer remember the fact that Government control of a small amount of land may be quite as effectual in the ultimate control of the development at the power site as if every element of that site were in public ownership. A small tract of land, even a fractional subdivision, located within a storage-reservoir site or along a diversion right of way has been sufficient to determine the control of the development. Having reached a decision on all the points above discussed, the engineer makes appropriate report. Detailed surveys are not attempted in reconnaissance work. Ap- proximate cross sections are taken at possible dam sites and, after the most feasible height of the dam is determined, a rough estimate of the area that would be submerged is made by means of the hand level. Where no profile of the stream channel is available, the fall over a short distance is determined with an aneroid barometer. This instrument, however, must be used with caution, especially during changeable weather. Photographs of all the critical points are taken. The possible dam sites suitable for storage or for diversion having been located and the type of development roughly determined, it is then necessary to consider the run-off. If the problem is one of storage, it will be sufficient to know the approximate mean annual run-off; the height of the storage dam can then be so fixed that the capacity of the reservoir may, as nearly as practicable, be sufficient to afford complete control. Of course, as a rule, sufficient storage capacity is not available, yet on the other hand there are situations in which the dam might be raised to a height that would give greater storage capacity than is necessary. In case no storage is to be pro- vided, the mean daily flow of the stream must, if possible, be deter- mined in order that the primary power capacity of the site may be appraised. If the available site is located in a canyon, it becomes necessary to determine within reasonable limits whether the maxi- mum fall may be secured by a low diversion dam and conduits or whether it would be more economical to obtain the necessary height by the construction of a high dam. Much of the land along the streams of the West has passed into private ownership, and where good facilities exist for the develop- ment of water power or the diversion of water for irrigation private interests may have established rights to the use of the water. An- other complication on many streams consists in the location of rail- road rights of way. Thus the problem of land classification may be 172 CLASSIFICATION OF THE PUBLIC LANDS. greatly complicated, and considerable thought and good judgment are required to determine on a plan whereby the stream may be uti- lized to a reasonable capacity and the vested rights already acquired by private owners may not be violated. Many of the power plants already installed use only a small percentage of the maximum avail- able power. In such cases either the plans for ultimate maximum power development involve the utilization and enlargement or im- ‘provement of such plants or they are omitted from consideration, it being assumed that when the demand for power increases to a certain point ordinary commercial procedure will settle all questions relative to the destiny of power plants in operation. : In case a railroad is already constructed parallel to the stream, plans for immediate development must avoid any interference with the railroad rights. Few plans that would require relocation of rail- roads are feasible under present market conditions, but the future demand for power will probably change the aspect of the case, and on this account the problem is treated as if the railroad did not exist, it being assumed that whenever the demand for power is sufficient to justify the expense of railroad relocation the power will be de- veloped. It is quite as desirable to provide means for future control by the Government in such an event as it is to provide such control in situations where no complications of this kind exist. Therefore, an important part of the field work consists in the determination of possible relocations, so that in fixing the value of any land reserved for a power site the department may have information whereby it can render an opinion as to the possibility and cost of relocating such lines as are already constructed or as to the feasibility of requiring the relocation of rights of way for which application may subse- quently be made. DETAILED FIELD INVESTIGATIONS. Investigations of detailed character are made to obtain data for final departmental action. The statements in the preceding section indicate that the chief object of the reconnaissance work is to locate lands suitable for power sites. The capacity of the power sites is determined in connection with such work largely for the purpose of justifying the preliminary withdrawal of the lands from entry. Incidental information of a more or less final character is collected during the reconnaissance examination, for the most part with a view to convenience and economy in the final detailed surveys. The withdrawals of lands for power sites on the basis of a reconnaissance examination are usually made liberal in extent, the purpose being to restore to entry any of the legal subdivisions which on detailed sur- vey prove to be of no value in connection with the plans finally CLASSIFICATION IN RELATION TO WATER RESOURCES. 173 adopted. The detailed investigation consists of surveys to determine river profiles, surveys of reservoir site, soundings at dam sites and other places, and a more or less careful examination of the charac- ter of the underlying formations that must serve as foundations, especially for dams. In addition, it is necessary to establish river gaging stations, if none have already been established, for the pur- pose of determining, with a high degree of accuracy, the amount of water discharged by the river, so that the economic capacity of the reservoirs and power plants may be determined. The gaging stations are selected, equipped, and maintained ac- cording to the standard methods followed by the United States Geological Survey in its regular hydrometric work. The processes are fully described in the annual progress reports on investigations of stream flow published by the Survey. The investigation of dam sites for the purpose of determining the security of the underlying formations that must serve as founda- tions has, up to the present time, been based largely on general geo- logic information concerning the holding qualities of the forma- tions known to exist in the localities examined. Final work of this character, none of which has been attempted in connection with the classifieation of water-power sites, will consist of the usual soundings and borings to determine the depth of the holding material, its permeability, its strength, and all the other factors that enter into its suitability for foundations. Special river surveys delineating the alinement and water-surface contours of streams and the topography of the adjacent land are made on a scale of 2 inches to the mile by the plane-table and stadia method. The survey maps are accompanied by profiles showing clearly the stream gradient. The contour interval on water surfaces is usually taken as 5 feet but may be increased to 25 or even to 100 feet for sections of steep slope where the delineation of a lesser in- terval could not be clearly made. The topography of the land adja- cent to the stream is shown by a contour interval of 25 feet and in general is carried to an elevation 100 feet above the stream by survey and an additional 100 feet by sketching. General features of cul- ture, gaging stations, existing hydraulic works, all lines of land sub- divisions by public survey, and other relevant data are shown on these maps. Promising reservoir and dam sites are shown with con- tour intervals of 5 feet to an elevation equal to the height of the possible dam. Engineers executing these surveys are instructed to obtain and furnish to the Washington office all available data as to the water resources involved, supplementing the data shown on the maps by detailed description of existing or proposed developments. 174 CLASSIFICATION OF THE PUBLIC LANDS. COMPILATION OF RESULTS AND REVISION OF WITHDRAWALS. When results of field investigation are available, much the same procedure is followed in the office in revising withdrawals as in making the preliminary withdrawals. The problem at this stage becomes one of limiting the withdrawals to the least possible area. ‘Careful scrutiny of plans and profiles of the streams makes it pos- sible to determine the power value of each smallest legal subdivision, and withdrawn areas containing no sites that are or may be valuable for the development of power are restored to the public domain. If the stream is of relatively flat gradient, where power development must be restricted to the low-head type and the construction will consist of power houses in conjunction with dams developing the available head, it is possible in many eases to locate definitely the favorable dam sites and divide the stream into successive units of probable development, from which no very great departure in con- struction is likely. On such streams the power-site reserves can be defined with a high degree of accuracy, and the use of each tract, whether for dam site, power-house site, flowage, or other purpose, can be forecast with considerable assurance. A minimum area of land is retained in power-site reserves on such streams. If the stream has a relatively steep gradient, however, where the natural development for power will consist of a low diversion dam and a long conduit leading to a power house perhaps several miles below and developing a high effective head, there can be a wide range of selection for the units of a comprehensive power project. On such a stream no specially favorable dam site is necessary, and relative expense of construction is generally the factor determining a choice among several different locations for the conduit. A definite use for any particular tract can seldom be assigned with development of this type, and the power-site reserve must be maintained so as to include all possible conduit locations if it is to be effective. A final revision of withdrawals along such a stream must be made as the power sites are developed. Even in such cases, however, restorations are fre- quently possible as soon as field examinations are made. Restorations are recommended by the Survey and recorded in the Survey files in much the same way as withdrawals. The usual form of power-site restoration is as follows: DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, November 12, 1912. The honorable the SECRETARY oF THE INTERIOR. Sir: Investigation of lands included in power-site reserve No, 117, Snake River, Idaho, indicates that the portion of the lands included therein described In the following order of restoration is not valuable for the conservation of CLASSIFICATION IN RELATION TO WATER RESOURCES. 175 water power, and I therefore recommend that the said order of restoration be submitted to the President for appropriate action. The area involved in this restoration is 85.7 acres. Very respectfully, Gro. OTrs SMITH, Director. DECEMBER 3, 1912. Respectfully referred to the President with favorable recommendation. WaLTerR L. FISHER, Secretary. ORDER OF RESTORATION No. 82. Snake River, Idaho. So much of the orders of withdrawal made heretofore for the purpose of re- serving water-power sites as affects the lands hereinafter described is hereby revoked. And it is further ordered that all of such lands not otherwise reserved or withdrawn are hereby restored to the public domain and shall become subject to settlement and entry under the laws applicable thereto upon such date and after such notice as may be determined upon by the Secretary of the Interior. Boise meridian. T.5 S., R. 4 EB, sec. 30, lot 6; ; sec. 32, lots 7 and &. Wo. H. Tart, DECEMBER 8, 1912. President. ADVERSE CLAIMS. {n many cases there is a conflict between the purposes of a power- site reserve and of some other claim to or proposed use of the lands affected. There is at present no satisfactory law under which land withdrawn for power purposes under the acts of June 25, 1910 (386 Stat., 847), and August 24, 1912 (37 Stat., 497), can be used for other purposes without jeopardizing the interest of the United States in the power possibilities. Under the acts relating to rights of way title to land by legal subdivisions is not granted and, as described elsewhere (p. 28), the interest of the United States may be preserved. Under the laws relating to agricultural land and mining, however, title to the land embraced in entries or claims passes from the United States and there appears to be no way in which the power estate may be satisfactorily reserved. Relative priority of reserve and claim, special exceptions, and relative value are the principles that govern in adjudicating the conflict. A power-site withdrawal is of no effect as against bona fide metalliferous mineral claims, without re- gard to priority of initiation. A power-site withdrawal is without effect as against a prior occupant or claimant of oil or gas lands who is diligently prosecuting work leading to discovery, but it becomes immediately effective against such occupant or claimant if diligent 176 CLASSIFICATION OF THE PUBLIC LANDS. prosecution of work leading to discovery is discontinued. A power- cite withdrawal is without effect as against a valid subsisting home- stead or desert-land entry or claim of valid settlement so long as it is maintained and perfected pursuant to law, but the withdrawal be- comes effective whenever the entryman or settler no longer continues to comply with the law under which the entry or settlement was nade. With the foregoing exceptions, a power-site withdrawal under the acts of June 25, 1910, and August 24, 1912, is effective against all claims or entries on which rights have not vested prior to the date of the withdrawal. Withdrawn lands having valuable possibilities for the develop- ment of power are alienated in the usual way if they are included in the excepted classes described above, although possibly the claims for such lands are subjected to a more careful scrutiny. If it ap- pears that the claimant is attempting to obtain title to land because of its value for power, and if its power value is greater than its value for the alleged purpose of the claim, patent may be refused and the entry canceled. Cases of this nature arise most frequently in connection with metalliferous mineral entries, although not a few power sites have been homesteaded or acquired under the timber and stone law. In the case of claims against which a power-site withdrawal is effective, a most unfortunate situation occasionally arises. For ex- ample, title to land may be sought by the application of scrip, and the claim may be initiated in advance of a power-site withdrawal. The claimant may have expended considerable sums’ in improve- . ment and cultivation and have proceeded throughout in good faith. Nevertheless, the land sought to be acquired may be worth for power many times its agricultural value, and when this dominant power | value is ascertained the land is naturally included in a power-site reserve. In such cases it is always a grave question whether the public interest is best served by the defeat. or ‘confirmation of the - claim. Under the strict rule of the law the claimant has no rights in the case. No provision of law makes it possible to give him agricultural rights and reserve to the United States the rights of: power development. Unless, therefore, the value of the land for the development of power is so great as to demand reservation for that purpose, public interest appears to sanction the claim of the individual as against that of the Nation, and elimination of the land from the power-site reserve is recommended NONPOWER CLASSIFICATION. In connection with the office studies incident to the report on the power-site possibilities of lands embraced in subsisting claims and with the investigation of power sites a mass of information is CLASSIFICATION IN RELATION TO WATER RESOURCES. 177 gradually being accumulated. This information is of negative as well as of positive character and shows where power sites are not located as well as where they are located. For convenience in mak- ing later reports on adjacent areas, this information is summarized from time to time and State maps are prepared showing the lands that are of no value for power development. This essentially con- stitutes a negative power classification and the use of such maps greatly facilitates the future work. In connection with these maps minutes are prepared in which are set forth the data on which the classification is based and the conclusions drawn therefrom. ADDITIONAL REQUIREMENTS TO MAKE POWER CLASSIFICATION EFFECTIVE. In order that the classification of land as chiefly valuable for the development of power may be made effective, it appears desirable that there be additional legislation providing for the control and utilization of land so classified under such conditions and regula- tions as Congress may decide to be necessary and for the proper administration of such land if, as now seems desirable, the title is to be retained in the United States. As a feature, or perhaps as a preliminary step in such legislation, a “separation act” would be desirable, providing for the disposition of power and agricultural estates independently of each other in a manner similar to that now provided for coal land and for oil and gas land in Utah. Such independent disposition of these estates is believed to be entirely feasible, because, except where reservoirs are provided, the land actually occupied by a power plant constitutes only a small part of the legal subdivisions on which the dam, flowagé water conduits, power house, and transmission lines are located. The bulk of the land is available for agricultural or other use and may be largely so utilized without detriment to the power development. The alienation of the agricultural estate and the retention of the water-power estate in any land, with provision for payment of proper damages to the agricultural estate when the power is devel- oped, appears to be practicable and desirable in the interest of the orderly development of the natural resources involved. In fact, a separation of estates and a disposition of each estate as such appear to be desirable, even though it may be decided not to retain control by the United States of the water-power estate. Whether or not a law providing for separation of the power estate is enacted, laws providing for the development of power on public land under such conditions that the industry would be materially encouraged and capital attracted would be most beneficial. The true purpose of power-site withdrawals is the use of valuable power lands primarily for developing power, not the withholding of such lands 78894°—Bull. 537—13—12 178 CLASSIFICATION OF THE PUBLIC LANDS. from any use. It is true that withdrawn lands are now available for use under the right of way acts, but they can be used for power de- velopment only under a permit revocable at will. Such a method is hopelessly inadequate and tends to discourage development. Recom- mendations for additional legislation have been repeatedly made by the department, and-several very satisfactory bills have been intro- duced in Congress, but so far no suitable laws have been enacted. CLASSIFICATION OF LANDS AS REGARDS IRRIGABILITY. FIELD METHODS. GENERAL CONSIDERATIONS. The general considerations and particular features already dis- cussed under “Classification of power sites” apply to the classifi- cation with respect to irrigability. They include determination of the relative value of water in its different uses and, in the case of reservoirs and headworks, the value of the land for other purposes. The field of investigation must be quite as broad and comprehensive for this purpose as for the classification of water-power sites. The engineer who performs the investigation is required to equip him- self with the preliminary facts available in the office, such as maps and records of stream flow, and his instrumental equipment is prac- tically the same as that already described. A suitable report on the classification of lands as regards irriga- bility should cover as many of the subjects listed in the following syllabus as may be relevant: I. Sources of data used in report: 1. Personal examination; route followed and time consumed. 2. Water-supply papers. 3. Maps. 4, Reports of engineers. 5. Miscellaneous. II. General introductory description: 1. Name of project. ' 2. Where located. 3. When started. 4, Estimated time of completion. 5. Concise description of project, including— (a) Area involved. (0) Source of water supply. (c) Outline of irrigation system. (d) Important or critical structures involved. 6. Nature and extent of control of the lands: (a) Carey Act. (0) Municipal district. (c) Ownership by developing company. (d) Contracts with land owners. (e) Contracts with desert-land or homestead entrymen who have no titles. : 7. Railroad and other transportation facilities, CLASSIFICATION IN RELATION TO WATER RESOURCES. 179 III. Rights of way: 1. Ownership and extent of those already secured. 2. Applicants for those pending. 3. Additional, across public lands, needed for the complete project. IV. The lands: : 1. Topography. 2. Geology. 3. Vegetation. 4. Soil: (a@) Soil analysis. (6) Depth of soil. (c) Depth to impervious strata. 5. Drainage. V. Climatology : 1. Temperature. 2. Precipitation. VI. Crops: 1. Kind of crops. 2. Probable markets. 3. Transportation to markets. VII. Value of lands: 1. Without irrigation. 2. Unimproved, but under ditch. 3. Improved and irrigated. VIII. Water supply: 1. Source of supply : (a) Discussion of stream. (6) Discussion of drainage basin. (c) Stream-flow measurements. (d) Storage already developed. Rig (€) Other storage possibilities. 2. Rights in water: (a4) Amount and date of water filing. (bo) Prior rights, adjudicated and unadjudicated. 3. Amount of water available for project. 4. Duty of water. 5. Amount of land that can be irrigated. IX. Character of irrigation works: 1. Storage dam. 2. Location. . General description. . Type of dam, material, etc. . Outlet tunnel. Area of reservoir. . Capacity of reservoir in acre-feet. . Diversion dam: (a) Location. (b) Type of dam, material, ete. (c) Size of dam. 9. Pumping: (a) Source, kind, and cost of power. (b) Lift. MARA 180 CLASSIFICATION OF THE PUBLIC LANDS, (c) Motors: (a) Number and kind. (b) Capacity of each. (d@) Pumps: (a) Number and kind. (b) Capacity of each. (e) Station equipment. (f) Transmission line. 4g) Buildings. (h) Pipe lines: (a) Kind, size, and capacity. (b) Thickness of material. (c) Length. (4) Receiving basins. X. Canals: 10. 11. PAAR wWNYH Size. . Grade. . Capacity. . Slopes. . Wasteways. Drops. . Lateral systems. . Flumes: (a) Kind (wood, metal, or concrete). (6) Size. (ce) Grade. (d) Capacity. (e) Carrier. (f) Foundation. (g) Description of construction. . Tunnels: (a) Length. (6) Size. Pipes: (a) Kind (wood, metal, or concrete). (b) Size. (c) Length. (d) Grade. (e) Capacity. (f) Pressure boxes. Gates: (a) Headgates: (a) Kind. (b) Size. (ec) Capacity. (d) Number. (e) Controlling device. (6) Lateral gates: Kind, ete. . Miscellaneous: (a) Bridges. (b) Trestles. (c) Riprapping. (d) Protection, CLASSIFICATION IN RELATION TO WATER RESOURCES. 181 XI. Cost of construction: 1. Detailed estimate. 2. Bases for estimate. XII. Present status of project: 1. Work completed: (a) Amount. (6) Character. (c) Criticisms. XIII. Revenue: . Water rights, . Number of acres covered. . Number of acres sold. Town sites. . State contract. . Settlers’ contract. ypendixes: 1. Maps. 2. Geologic sheets. 3. Photographs. 4. Precipitation records. 5. Stream-flow records. XV. Suggestions. Recommendations. Conclusions. Extensions. Omen XIV. A SS To determine whether or not an area of land is commercially feasible of reclamation by irrigation the following matters require especially careful study: Available water supply. Present utilization of water for irrigation. Duty of water. Character of lands to be irrigated. Crops. Character of irrigation works. AVAILABLE WATER SUPPLY. To determine the available water supply a careful investigation is made of the streams from which the water is to be diverted. A study is made of all stream-flow measurements, and if records of daily discharge are available for a number of years, hydrographs are prepared showing graphically the daily fluctuations of the stream. On these hydrographs a line may be drawn representing the equivalent of prior rights. This done, the unutilized flow may be readily determined. Where irrigation has been practiced for a number of years, these hydrographs may show clearly that the normal flow during the irrigation season is already appropriated and that the unutilized flow occurs during the winter and during flood stages. To utilize fully the run-off from the streams: under such conditions reservoirs must be constructed to store the water that is now wasted. 182 CLASSIFICATION OF THE PUBLIC LANDS. The study of available water supply therefore involves an investiga- tion of the possibilities of storage. Unless information is available from private surveys, a reconnaissance examination is made of the drainage area for the purpose of locating storage sites. The methods followed are merely approximate and do not differ from those used in reconnaissance power surveys. If no actual records are available showing the discharge of the stream, it is necessary to establish gaging stations at once and make a careful study of the drainage area and records of precipitation. If reliable maps are available from which the area of the drainage basin can be measured, and records are available showing the average precipitation on the basin, it is then possible to figure roughly the probable run-off. This method of determining the available water supply is unsafe and is used only where no records of discharge are available. : After determining the gross run-off from the basin the unutilized flow or the water available for the reclamation of new lands is deter- mined by deducting the amount of water required to satisfy prior appropriators. PRESENT UTILIZATION OF WATER FOR IRRIGATION. Mention has already been made of the necessity for allowing for prior water rights in determining the amount of land that can be successfully irrigated from any stream. Irrigation systems already installed at the time of the examination furnish one of the most troublesome problems the engineer has to investigate. Under the law, as usually interpreted in the West, the water is public property, permission for its use being granted by the State, and wherever lands are classified for irrigation in the West it is nearly always true that the State has granted prior rights to the use of the water. In the earlier days of irrigation these rights were granted with the utmost liberality, without much regard for the amount of water actually flowing in a stream. It is therefore common to find that these prior rights exceed in aggregate amount the volume of water carried by the stream during irrigation seasons. This condition has been recognized by persons desiring to use water from such streams, and many of them have secured rights to use the flood waters which flow in the stream channels at periods of the year when irrigation is not practiced. Such utilization is dependent, of course, on the construction of storage reservoirs. Thus it may occur that, however well adapted for agriculture a piece of public land may be, on superficial examination there appears to be no available water for its reclamation. It is necessary for the engineer to bear in mind the liberality with which prior rights have been conferred and to examine CLASSIFICATION IN RELATION TO WATER RESOURCES. 183 the records for the purpose of determining what proportion of the water so granted can be beneficially used for irrigation. Such a study involves a determination of the duty of water, a subject which is dis- cussed below. It is clear, however, that the determination ot’ beneficial use involves an examination of the reservoirs, headworks, canals, and ditches, and the amount of lands embraced in irrigation systems under operation, and this is frequently a most difficult mat- ter. It is the rule rather than the exception that the irrigator uses more water than is necessary for the growth and maturity of his crops; indeed, his use of water is not uncommonly so extravagant that the agricultural value of his land is greatly damaged. On few of the irrigation systems of the West, especially the older ones, has any record of the amount of water used been collected or preserved or the capacity of the irrigation canals been determined. This capac- ity may be variable, depending largely on the care with which the canals are maintained. Thus the engineer is obliged to investigate thoroughly all the working features of the systems already installed, so that he may make a report as to the actual amount of water neces- sary and thereby determine how much if any is available for the irri- gation of new lands. Water-right matters are usually complicated and a proper study of them requires some working knowledge of the water laws and the decisions relating thereto. Although in many of the Western States the water laws are similar, they differ in some respects and some of the differences are very wide. To cover all the necessary points the engineer must examine into the grants and ad- judications at the county or State offices where such matters are on record. Closely connected with this study of water laws is the obser- vation and possibly the measurement of flow in existing canals to determine seepage losses. Such losses frequently represent 50 per cent or more of the water that is diverted from the streams, and it is necessary to consider the question of preventing such losses so that the water may be applied to lands not under cultivation. Where ex- travagant use or unreasonable loss is discovered the question then arises whether that water may not be filed upon for the benefit of the new lands under consideration. The determination of this point usually requires adjudication either by the courts or by State officials appointed for this specific purpose. DUTY OF WATER. The determination of the duty of water, or the amount of water necessary to irrigate a piece of arid land suitably, is another difficult . task of the engineer. In some parts of the West the necessary amount. of water has been determined by scientific study. Over the greater: portion of this region, however, the amount has been determined 184 CLASSIFICATION OF THE PUBLIC LANDS. largely by experience, so-called, and has usually been greater than is necessary. Frequently the lower limit has been determined in dry seasons when the supply of water was meager. Therefore the duty of water is susceptible of a very flexible interpretation. On each irrigation project there is a generally accepted idea of the amount necessary, and whether a larger or smaller amount than this is de- livered by the canals is rarely determined. As a rule, however, the discriminating engineer can, by examining all the evidence, fix upon an approximate standard that may be considered reasonable, and unless that standard approaches too closely the total amount of water available adjustment is comparatively easy. Determination of the duty of water is, after all, an agricultural problem, some crops re- quiring more than others on the same land and different kinds of soils requiring different amounts for the same crops. Having deter- mined this amount, the engineer then measures or estimates the losses which occur in transmission through canals and other conduits from the source of supply to the cultivated fields, for duty of water is, unless otherwise specified, referred to the field itself. This amount is sometimes called the net duty. To the amount required for actual application to the crops must be added that lost by seep- age and by evaporation, and the farther the supply from the place of utilization the greater the amount which must be allowed for such losses. It is necessary also to consider losses in the storage reser- voirs, especially the loss due to evaporation. Having summed up all these items and having previously determined the total supply available, the engineer can then determine how much is available for new lands. To this quantity is applied the duty previously deter- mined, allowance being made for the prospective losses in the con- duits that will carry the water to the new land. The result of this computation will show the amount of new land that can be irrigated. CHARACTER OF LAND TO BE IRRIGATED. The elements in the investigation of the character of the lands to be irrigated include topography, geology, character and depth of soil, and general drainage conditions. These are partly engineering and partly agricultural factors, but the engineer must take them all into consideration, because it is apparent that, with a given prospec- tive cost of irrigation, a project would be feasible if the soil and physical conditions were of one kind and not feasible if those condi- tions were of another kind. The climate is another essential factor, and a study must also be made of the kind of crops adapted to the particular locality. It is apparent that a greater investment can be made for irrigation:in a region adapted to citrus fruits than in one where, on account of climate,-soil, or altitude, hay is the: principal possible commodity. The determination of these points by the engi- CLASSIFICATION IN RELATION TO WATER RESOURCES, 185 neer rests largely on his general knowledge of related conditions and on the experience that has been gained by the people in the region. The transportation facilities and the market are subject to change and should usually be considered merely to determine whether pres- ent or future development is desirable. Transportation facilities will, under ordinary conditions, be provided in response to produc- tion, and market is a feature which, in the long run and under the present conditions of rapid growth and consumption in this country, will ultimately offer few difficulties. CHARACTER OF IRRIGATION WORKS. Having reached a favorable determination as to water supply, duty of water, and the economic features above set forth, the engineer must then investigate the character of irrigation works that are adapted to the physical conditions of the area. The character of such works depends entirely on the physical problems to be met. It may be necessary to construct storage reservoirs in order to utilize the high- est possible proportion of the available water. On the other hand, the source of supply may be a very large stream, having a capacity sufficient to furnish all the water required for practicable irriga- tion in the entire region, and the studies are then confined to the determination of suitable diversion sites and canal routes reaching from the headworks to the lands to be irrigated. As in the case of reconnaissance power surveys, no final locations are determined by the engineer, it being considered preferable to leave such matters of detail to those who may in the future develop the project. The location of the headworks and of reservoirs and the routes, lengths, and capacities of canals can be determined approximately by field investigation of the type herein described, and while the results may be inaccurate for purposes of final location and development, they are sufficient to afford information suitable for departmental action. The public lands located in reservoir sites or along the courses of prospective conduits are carefully considered by the engineer with respect to their relation to the ultimate problem under consideration. METHODS OF CLASSIFICATION. PROCEDURE UNDER THE CAREY ACT In the administration of the Carey Act and its amendments classi- fication of lands with respect to irrigability is a necessary incident, for under the conditions of this act the land granted must be non- mineral, desert, and irrigable. The first step in the present pro- cedure is the withdrawal of lands under the act of March 15, 1910 (36 Stat., 237), at the solicitation of the State in which the lands are 186 CLASSIFICATION OF THE PUBLIC LANDS. situated. This is essentially a withdrawal for the purpose of classifi- cation, and the area withdrawn may be far in excess of that eventu- ally constituting the irrigable area of the project. The withdrawal is made on the assumption that the area includes some land sus- ceptible of irrigation under the Carey Act, but investigation may show this not to be the case. During the period of withdrawal, which is limited to one year, the promoter of the project has oppor- tunity to investigate the area, plan the details of the project, and make a reliable classification as to irrigability without fear of aliena- tion of the lands and resulting interference with the successful con- duct of the project. In case such investigations and a request by the State for segregation are not made, the land is restored to the public domain without classification. If, on the other hand, the plans for the project are perfected and application for segregation is made, the lands listed in the application are further reserved until action is taken on the case, and the remainder of the withdrawn lands are restored to the public domain and may thereafter be assumed to be nonirrigable. The regulations require that the application for segre- gation shall include full data to show that the land is nonmineral and desert land and is irrigable and that the project is feasible. A field investigation is made by the General Land Office and the case is referred to the Geological Survey for report. A careful analysis of the water supply of the project is then made by the Survey, and sufficient investigation of probable costs and returns is made to show whether the reclamation and settlement can probably be accomplished at a cost warranted by the value of the reclaimed lands. If the existing data relative to the amount of water available for the project are insufficient to warrant a reasonably definite conclusion as to the area that can probably be irrigated, a hydraulic engineer of the Geological Survey may be called upon to supplement them by stream gagings and such other determinations as seem advisable. When all the data are considered, an estimate of the allowable area is prepared and a definite report and recommendation on the case are made. Final adjustment of the area to be segregated and of the terms of the contract between the Secretary of the Interior and the State devolves upon the General Land Office. The approval of the segregation list under present departmental practice is in effect a fairly reliable classification of the land as non- mineral, desert, and irrigable. The aim of the work as now con- ducted is to safeguard the welfare of prospective settlers, the neces- sary investment of capital, and the interest of the Government. Some attention is being paid also to construction and settlement on Carey Act projects. When data obtained after the segregation is made indicate that the area included in a project exceeds the land CLASSIFICATION IN RELATION TO WATER RESOURCES. 187 that can be successfully irrigated, or when it is learned that con- structing companies are attempting to increase the area of the project by selling water rights to owners of private lands and thus depriving the segregated lands of a portion of the water supply necessary for their complete reclamation, conferences are held with State authori- ties and prompt measures are taken to insure the protection of the settlers. It is hoped by such means to avoid the disastrous results that have heretofore too often attended operation under the Carey Act, to eliminate speculation, so far as possible, and to insure, so far as the department has the power, that the settler who seeks a home on segregated lands will receive a sufficient. area of land with a satis- factory water right at a reasonable cost. IRRIGATION RESERVOIR SITES. Withdrawals of sites for irrigation reservoirs under the acts of June 25, 1910 (36 Stat., 847), and August 24, 1912 (37 Stat., 497), ire made in the same way as withdrawals of power sites whenever the investigations of the Geological Survey indicate that feasible locations exist. Such withdrawals are made in the interest of bona fide development and to withhold from adverse possession reservoirs required in connection with large irrigation projects, both public and private. Modifications of the withdrawals to permit occupation and use of the sites under the applicable right of way acts are made when the development is warranted and applications for modification are made by responsible parties. PROCEDURE UNDER THE ENLARGED-HOMESTEAD ACT. The classification of lands under the enlarged-homestead acts also devolves upon the Geological Survey, the Director having been instructed by the Secretary of the Interior to make recommendations of lands suitable for designation thereunder. Nearly 193,000,000 acres of land have been designated in the States to which the pro- visions of the acts apply. Of this area, approximately 157,000,000 acres were designated within three months after the passage of the earlier acts. This result was achieved in part by the use of topo- graphic maps, the accumulation of 385 years of work, in connection with a large number of which unpublished land-classification sheets were on file; in part by the application of available data on rainfall, run-off, and stream flow; in part by consultation with the Reclama- tion Service; and in part by the cooperation of the several State engineers. In spite of the uncertainty incident to rapid work cov- ering large areas, ‘later information has shown that these designa- tions were in general properly made. The cancellations of erroneous designations amount in the aggregate to about 615,000 acres, or less 188 CLASSIFICATION OF THE PUBLIC LANDS. than 0.4 per cent of the early designations. Since the first general designations were made numerous requests for the designation of additional areas have been received, and the work incident to the designation of lands under the enlarged-homestead acts now consists largely of the consideration of such requests, with office and field studies to determine whether the lands involved may properly be designated. The office studies include investigation of township plats, topographic maps, records of irrigation projects, rainfall and stream-flow data, and other sources of information from which a conclusion as to the suitability of the land for designation may be reached. In case field examination is made, the results are used in the office studies preceding designation. Not all nonirrigable lands, however, may properly be designated, for it would obviously be useless to designate lands that could not be entered under the acts. Unsurveyed lands are not designated and newly surveyed lands are, by departmental order, withheld from designation until six months after the filing of the approved plats of survey in the local land office. Patented lands are, of course, not lands of the United States and are therefore eliminated from pro- posed designation. Lands on which there is sufficient rainfall for the production of ordinary crops without recourse to unusual methods of cultivation are not designated. Lands on which there is merchant- able timber or which contain valuable minerals other than coal (in Utah coal, oil, or gas) are not properly subject to designation. Coal lands and in Utah coal, oil, or gas lands may be designated and en- tered subject to the terms of the acts providing for agricultural en- tries of the surface rights on such lands. Lands included in with- drawals or reservations of any kind or in Carey Act segregations are not properly subject to designation. Lands entered and in process of acquisition under the public-land laws may be designated if other- wise subject to the act, but lands included in subsisting entries under the desert-land act, being prima facie irrigable lands, are not prop- erly subject to designation. Lands including sections granted to States as school lands are not designated unless they are excepted from the school grant. Although no form of petition is specified for the use of those re- questing the designation of lands under the enlarged-homestead acts, it is desired, in order that the Survey may have such information concerning the character of the land as the petitioner can “supply, that such petitions be made on the usual form of application for entry of such lands, wherein the applicant sets forth under oath state- ments as to important features of the character of the land. Where this form is not used an affidavit setting forth essentially the same in- formation is requested of the petitioner. CLASSIFICATION IN RELATION TO WATER RESOURCES. 189 Orders of designation originating in the Geological Survey have been serially numbered both with general and State numbers. The form of letter and order used is here shown: DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, Washington, January 6, 1913. The honorable the SECRETARY OF THE INTERIOR. Sir: The following areas of land to which the enlarged-homestead act of February 19, 1909 (35 Stat., 689), as construed by the department, is applicable are, in my opinion, not susceptible of successful irrigation at a reasonable cost from any known source of water supply, and I therefore recommend their designation under the said act: ENLARGED-HOMESTEAD DESIGNATION No. 210. Montana No. 59. Montana meridian, Montana. T.9 N., R. 7 E., sec. 22, lots 2, 3, 4, and 5, NW. } of SE. }. {Here follows remainder of land description. ] The above-listed lands will be enterable under the provisions of the en- larged-homestead act in so far as they may be vacant, public, nontimbered, and nonmineral and unaffected by any special provision of law, withdrawal, or reservation inconsistent with the provisions of said act. The surface of coal lands may, however, be entered subject to the reservation of the coal to the Government. The area included in this designation is approximately 1,485 acres. None. of the lands listed above are withdrawn in oil, phosphate, or power-site re- serves. Very respectfully, Gxo. Otis SMITH, Director. Approved January 28, 1913, and referred to the General Land Office tu be- come effective February” 27, 19138. SAMUEL ADAMS, First Assistant Secretary. The office record of the Survey relating to enlarged-homestead designations consists of State maps on which the designated lands are platted, a file of orders of designation arranged by serial num- bers, a file of minutes similarly arranged showing the data on which the designation is based, and township cards on which are platted the designated areas. Cancellations are similarly recorded and filed, all designations and cancellations affecting any township, however, being shown on a single township card. 190 CLASSIFICATION OF THE PUBLIC LANDS. CLASSIFICATION AS REGARDS DOMESTIC USE. GENERAL PRINCIPLES. The problem of domestic water supply in an arid region is closely associated with the agricultural development of the region. In the broadest meaning of the term the use of water for domestic purposes includes not only its use in the household but by farm animals, by cattle on the range, and by the prospector in the desert wastes. Permanent agricultural settlement depends on the presence of a water supply suitable for household purposes and for farm use. Under homestead laws requiring as their fundamental conditions both residence and cultivation, the extension of settlement to new areas is possible only where the prospective homesteader finds water within a reasonable distance of his chosen location. Where water suitable for such use does not exist on the surface the homesteader must resort to wells; failing there, he must haul water. The labor and therefore the expense of hauling water are great. Uncleanliness and insanitation are almost enforced by the resulting economy of use. The conditions of water storage on the homestead do not usually tend to insure purity and frequently cause disease. The possibility of procuring a domestic water supply from wells in regions where surface waters are impure or altogether absent is thus a question of great importance. In areas where the underground water resources are unexplored geologic investigation may determine the more favorable localities for putting down test wells, and in regions where the position of the water table is not known or is known but imperfectly the applica- tion of principles well known to the geologist may be of great assist- ance to the farmer and the well driller in forecasting the possibili- ties. To this end large areas in the arid region have been geologically investigated. The data relative to underground waters have been compiled and maps prepared, not only showing the position of the water table in proved areas but indicating the probable location of the water table in adjacent unexplored areas. The data thus obtained by the Geological Survey, many of them in cooperation with the States, are published and widely distributed in water-supply and pro- fessional papers. FARM WATER SUPPLY. A modification of the homestead laws to relieve the entryman of the necessity of residence on lands where a domestic water supply is not available and can not be obtained is operative in Idaho and Utah under the enlarged-homestead acts, whose provisions have been men- tioned. The provision in these acts relating to domestic water supply CLASSIFICATION IN RELATION TO WATER RESOURCES. 191 has been construed by the Department of the Interior as referring not only to surface waters but to the underground waters which could be reached by wells of reasonable depth. In determining the existence of such a domestic water supply and in recommending suitable lands for designation under the provisions of these acts, in regions where no potable surface waters exist, the Geological Survey takes into consideration the depth below the surface and the quality of the underground water, the amount of labor necessary to reach it by a well, and the cost of development compared with the agricultural value of the lands. The provisions of the law are con- sidered particularly applicable to areas where substantial but fruit- less efforts have been made to obtain such a water supply by digging wells. In procuring data for classification of lands ofthis class the Geological Survey has been assisted by special agents of the General Land Office. To January 1, 1918, areas comprising 1,199,638 acres had been designated in Utah and 7,801 acres in Idaho as not having a suitable domestic water supply. RANGE WATER SUPPLY. The problem of the disposition of grazing lands is still largely unsettled. By the creation of national forests a large part of the summer range has come under the general scheme of forest adminis- tration and is leased by the Forest Service at a specified price per capita, but the unreserved public lands still include considerable areas of summer range, much of the fall and spring range, and a iarge proportion of the winter range. The control of the spring, summer, and fall range is rapidly passing into the hands of indi- viduals and live-stock associations, not in general by securing title to the public lands as a whole but by the simple expedient of acquiring title to the water holes. The owner of the springs and streams located on an otherwise waterless range has obtained the use of the grazing land on far more favorable terms than if he had acquired absolute ownership. He is free from State land tax, he pays no rent to the Government, and no rival sheep or cattleman may water at his wells. Except for the period when snow, by providing water, may make invasions by rival stockmen possible, he is secure in his possession. As a remedy for this situation, disposition of the grazing lands by sale and by lease has been‘ advocated, and several bills dealing with the situation have been introduced in Congress. If, as is advocated by the Interior Department, a leasing system is adopted, it is ap- parent that the Government would be at a serious disadvantage in proper administration unless watering places were also available for lease. As a step in the working out of a definite policy for the ad- ministration of public grazing lands outside of national forests the 192 CLASSIFICATION OF THE PUBLIC LANDS. withdrawal of public watering places under the authority conferred by the acts of June 25, 1910 (36 Stat., 847), and August 24, 1912 (37 Stat., 497), has been sanctioned by the President. The first with- drawal for this purpose was approved by him on March 29, 1912. The effect of withdrawals of this character is to prevent alienation of the lands pending legislation governing their use under public control, but the use of the watering places by all is meantime possible under such conditions that no user can acquire the right of permanent exclusive occupation. These withdrawals are based upon field investigation by members of the Geological Survey and some of them on reports of General Land Office inspectors. Careful consideration is given to the rela- tion of the watering place to the surrounding range and its value in connection with grazing on the public lands. Agricultural lands sus- ceptible of successful cultivation have been excluded from with- drawal except in regions where most of the watering places have passed into private ownership and it becomes imperative to reserve water for stock, even at the expense of settlement. MUNICIPAL WATER SUPPLY. An incidental classification of lands as valuable for domestic water supply arises through right of way applications for municipal sys- tems. In general, where sources of water supply are sought for municipal purposes their value therefor far exceeds their value for power or irrigation. Approval of such right of way applications therefore amounts to a definite classification of the lands affected. The lands may be used for reservoirs, conduits, stream protection, or any other purpose relating to municipal water supply. Such right of way applications are referred to the Geological Survey for report. In view of the relatively high value of water for municipal supply, the question whether the application provides for the highest use is seldom considered. The most troublesome question is to determine whether the application is really made for municipal purposes. If the application is made by a municipality this ques- tion is readily answered, but if a private water company makes the application it may be difficult to determine whether the purpose is private or municipal. A strict showing of municipal authorization to the private company is required in such cases and constitutes the chief criterion for classification. Lands embraced in permits for municipal water supply are with-) drawn and reserved in order that occupation in the interests of the municipality may be suitably protected. INDEX. Fs Page. Agricultural land laws, acquisition of mineral land under-__ 36 provisions of ~_--______________ 20-23 purpose of. .--2-s aco ses seen. 20 See also WHomesteads; Desert land; Timber and _ stone land. Agricultural lands, existing public domain in=...---==-~ 8 Agriculture, information as to, from elassification_____-_____-- 156 Apex, Jaw fp -2-sssese oc. 24, 39, 48 Appalachian field, oil in-_--_-____ 116 Applicant’s affidavits, classification bY sasasseeecsencssscese. 33 Arizona, enlarged homesteads in___ 22 Asbestos, occurrence of____---~__-- 140 Ashley, G. Hs work of._.....-.-.. 9 Asphalt, occurrence of_____---_--_ 140 Assessment work, requirement of_ 24, 25, 49 Authorship, division of__-__-__--__ 9-11 B. Ball, M. W., work of_------------ 9 Base maps. See Topographic maps. Borax, occurrence of__--__------- 139 Building stone, deposits of, laws con- G@IMmin ge. 622 ee 25-26 Cc. California, oi] in___-_-___-_--_----- 117 Calkins, F. C., work of--_-_-------~- 10 Campbell, M. R., work of__-_------ 11 Canals. See Irrigation canals___-- 28 Carey Act, proceedings under__._._ 185-187 provisions of__.______--_------- 30-31 Chance, H. M., curves of, use of, in valuing coal lands_—-_-_-- 83 Clark, I, Ba work of.icnnsncacans 10 Classification. See Land classifica- ' tion; Water supply. Coal, attitude of, allowance for, in classification__--—---~ 70-73, 92 attitude of, allowance for, in valuation___.__-_-------- 87-92 determination of -_--------- 105 broken beds of, allowance for, in classification___--------- 70 allowance for, in classifica- tion, chart showing------ 1 burned beds of, allowance for, in valuation____----~------ 79 depth to, allowance for, in classi- fication ~---- dbeeeee=: 73-78 allowance for, in valuation-75, 91-93 73894°—Bull. 537—13 13 Coal, depth of, determination of____ depth of, limits of, chart show- INS Soo ce nee cet 75 irregular beds of, allowance for, in classification__._____-_ allowance for, in valuation__ 87-90 ehart showing ~--------- 89 mining cost of, allowance for, in VelUatiOn 222s o-e oe oas 82 figure showing _______-__-_-__ 85 multiple beds of, valuation of_-_ 93 quality of, allowance for, in classification_______--___ 68-69 allowance for, in valuation__ 82 determination of _-_ 59, 68, 105-108 royalty Olio ssss2s5222=25555-2= 80-81 sampling of, method of___-___-_ thickness of, allowance for, in classification________-___ 69-73 allowance for, in valuation__ 83-90 determination of _-------_ 100-104 value of, in ground ---_------__ 79-81 weathering of, depreciation by__ 78-79 workability of, allowance for, in classification_________-__ 66-78 See also Coal lands; Coal beds. Coal beds, persistence of.___-_--~ 100-104 persistence of, uncertainty of__- 94 Coal lands, access to, by rail, allow- ante: LO. soneenee ees 95 acquisition of, under agricultural land! laws 22-o25-s-.4222. 36 area of, still belonging to United States. .:-----s.---.-== 8 classification of, authority for___ 65 factors involved in_-______-_- 67-78 field methods of--_ 50-53, 59-60 methods of ~~--_-------- 66-79 organization for______--_ 16-17 principles involved in---_ 66-67 procedure in----~-~--~ 108-110 progress in----------~--- 111 purpose of___-__--------- 65-66 review of___-- 95 regulations for 96 coal in, value of, in ground____ 79-81 extent of_..__<==s=ss-==-- 100-108 faults in, allowance for_------- 93 field work on_---~----------- 98-108 40-acre tracts of, classification DY prema eee wees 78,99 geographic location of.___-__--- 99 geology of, necessity for field de- termination of _-------- 99-100 intrusions in, allowance for----- 94 laws concerning ~-_-_---~ 27, 37, 45-46 maximum price of----.-------- 95 193 194 Coal lands, prices of___-_.-------- restorations of valuation of -._-.-._-_---__-- allowance for faults in-_---- 93 diagram used in difficulty of... = factors: it) o- eco oles allowance for maximum of_-___-.-_----_- procedure in___________-- regulations for_ value per acre of___--__---__ 90-91, 95 withdrawals of__._____ 36-37, 52, 65-66 rules. for = 22sec o ees 37 typical form of.____-________ 65-66 See also Coal; Coal beds. Coal section, organization of__-_---~ 16 Work Of so csie Se eek eee 16-17 Colorado, enlarged homesteads in__~ 22, Ol 1D aso ee eee eee cees 117 Colville Indian Reservation, failure to classify lands in-_____ 144 Contour lines, explanation of ______ 57 Crystalline rocks, occurrence of oil UN ose coos 113 D. ‘Dam sites, physical details of___-_ 173 See also Water-supply sites. Desert-land laws, provisions of_____ 22 Domestic use, classification for__ 190-192 classification for, general princi- Dles(0fie22 2.5222 ce CS 190 See also Enlarged homesteads ; Municipal use; Range. Duty of water, allowance for, in classification _--__-______ 183-184 BE. Elevations, determination of -__.____ 57 Enlarged-homestead law, proceed- ings under____ 187-189, 190-191 provisions of__-____-------_-___ 22 Entries, fraudulent, defeat of, by classification ___._-_--__ 144-145 F. Farm use, water for. See Enlarged- homestead law. Faults, allowance for, in valuing coal lands ---_--_---____ 93 Field methods of classification, de- velopment of___-_----.___ 50-53 outline of---_--_-----_--__-__ 98-108 See also Surveys; particular classes of lands. Finch, B. H., work of-..-...-_____ 10 Float, investigation of_______ - 151-153 Florida, phosphate reserves in______ 125 Forest homestead laws, provisions i earn i ctgs apes ales 21 Forty-acre tracts, classification by-_ 73 G. Page, Gaging stations, establishment of. 173, 182 Gale, H. S., work of__------------~ 10 Gas. See Oil and gas. General Land Office, cooperation With) 252 eee ees 13 Geological Survey, U. S8., classifica- tion by. classification by, POR ites aie history of --- evolution of topographic maps of__-__--_____ 14 Graphite, occurrence of____--__-___ 140 Grover, N. C., work of___ ae 10 Guano, occurrence of_- = 140 Gypsum, occurrence of__--_--___-= 139 H. Halite, occurrence of___-____--.--_ 139 Hayes, C. W., work of-___----____ 11 Heroy, W. B., work of__-_________- 10 Homesteads, laws for, provisions of. 21-22 relation of, to pubiic-land with- to power-site withdrawals___ 176 See also Enlarged homesteads. Hydrographic classification--___ 16, 17-18 I. Idaho, enlarged homestead in____ 190-191 phosphates in —--.___-_--__-__ 127 Indiana, oil 116-117 Indian reservations, classification of lands of ~2-ss=2s==ss= 143-144 Internal improvement, land grants POR so i eee fees 30 Irrigation, character of land for. 184~-185 classification for___ -- 178-189 factors in. 2-----2.-. 181-185 general considerations in__ 178~181 methods of______._-_--~. 185-189 duty of water in----___-___ 183-184 water available for__._______ 181-182 water utilized for____._--____ 182-183 withdrawals for_____________ 185-187 works for, character of, allow- anee: fotos ee ose 185 See also Enlarged homestead. Irrigation canals, right of way for, laws concerning_________ 28 water in, loss of.._-_-__________ 183 Irrigation reservoir sites, with- drawals of ----.________ 187 Irrigation section, organization of__ 17 WOTK Ofcccsesemee cocoon. 17 Irrigation surveys, development of__ 14-15 Isolated tracts, laws concerning___ 23 K. Kansas, Gil ims. ve 117 King, Clarence, report of, on land classification__..________ 12-13 INDEX. 195. Ik Page. Page. Mineral lands, data on, preparation Land classification, agencies of__.__ 33-43 Wo sek eeweneas eaeeeos 63-63- data for, chart showing---___-_ 63 valuation of 79-95 reports on-----~----- ---. 63-65 See also Coal lands; Oil and gas history Of jose ssse oss eee 18-50 lands; Phosphate lands; laws: for 222.2225 Sees 12, 18-32 Potash lands; Miscellane- See also Public-land laws; ous minerals; Mineral Land grants. lands, metalliferous. methods of____-----__-- 33-50, 66-79 | Mineral lands, metalliferous, claims necessity folsuois.s sei ousceun 32-33 for, precedence over wa- organization for, development of_ 11 ter-supply rights _-_._-__ 175 policy’ Of 2.22222 252 225225255 9 classification of, agencies of____ 145 purposé Of. .-s.2e2scee essen 7-9 field work in.--.--._--__ 146-155 See also Water supply; particu- methods of__ — 145-155 lar classes of land. problems of__ ~ 145-146 Land-classification board, organiza- procedure in_-_-_-__ wots 146 tion of. ~- 13, 15-18 purposes of______-_ — 142-145 records of _--.------------- 16-17, 18 laws for, provisions of_ --- 23-29 Land grants. See State grants; Rail- leasing oto osseesoueceooesees= 48 road grants. withdrawals of __-______ 40-41, 44-45 Land Office field service, classifica- Mining, aid to, from classification. 157-158 HON bys escent 384-35 | Mining uses, right of way for, laws Land Office maps, use of, in coal concerning______________ 29 classification ~---__--.---_ 58-60 | Miscellaneous minerals, data on__ 140-141 Lands, alienation of _______-____-- 7 lands containing, withdrawal of. 142 character of, allowance for, in laws on--~~---~ aos 140 classification __._______ 184-185 occurrence of___ ~ 138-140 classification of. See Land classi- Missouri, oil in ~------_-_ see JIT fication. Monazite, occurrence of___-----_-- 139 utilization of _-_-_.____-----_-- 7 | Montana, enlarged homesteads in_-~ 22 value of, determination of_ = 7-8 | Municipal use, water supplies for, La Rue, E. C., work of_ as 10 right of way for_---.-_ 29,192 Leasing, desirability of-__.--_-- 46, 47-49 proposed allotment to States N, trout - a0 National Academy of Sciences, re- returns from_——_~_------~------ 49 a Legislation, desirable, outline of. 46-50, port of, on land classifica- TON se scne nee eee ees 11 rai Nevada, enlarged homestead i 22 See also Withdrawals; Land . ee eee eS classification: Mineral New Mexico, enlarged homestead in_ 22 lands; ete. OU, Masons sna aea a sae eee oe ait Leighton, M. 0., work of---------- 10 Northrop, J. D., work of---_------ 10 Lesher, C. E., work of------------ 10 0. Lindgren, Waldemar, work of_----- 11 | Ohio, off in--------------__--__- 116 Lodes, investigation of claims for_- 148-155 Oil, depth to, allowance for, in laws concerning____------~ 24-25, 140 classification__________ 120-121 sampling of_---------------- 154-155 quality of, allowance for, in M classification______---~ 119-120 ; Oil and gas, accumulations of, de- Magnesite, occurrence of --_-_----- 140 pendence of, on struc- Maps, construction of, for coal ture ~_~~------------- 114-116 classification.____-_----- 51-53 accumulations of, position of__ 112-116 improvement ihe ce 50 migration of_-—---_--- sss-5 aaa 112 Sce also Topographic maps. occurrence of, distribution of. 116-117 Mendenhall, W. C., work of-------- 9 factors in_--------~----- 112-116 Metalliferous mineral lands. See surface indications of_-_--- 116 Mineral lands, metallifer- See also Oil and gas lands. ous. Oil and gas lands, adverse water-site Milling uses, right of way for, laws claims and, relations of. 175-176 concerning ~------------ 29 area of, still belonging to United Mineral classification, organization Slates o-oo pas kasssRSets . , fOP2sekee sed Sees 16-17, 18 classification of. -—- dill Mineral lands, classification of, by- data for--~--------------~- 118 products of____------ 155-159 factors in --------------- fis- Tel classification of, field methods of. method of -~--------------- 118 See Field methods, purpose of-----------~------ 117 196 INDEX. Page. Oil and gas lands, laws concerning 26, 39 léasing, of..--2-—.----+--===+- 47-48 restorations of--__---------- 122-123 withdrawals of-. 38-39, 44, 46, 121-122 legal authority for___-----~ 43-44 See also Oil and gas; Oil rock. Oil and gas section, organization of_ 17 work of. 222-0 ee 17 Oil fields in United States, positions (1) aa a ee 116-117 Oil rock, character of___------_--- 119 depth fae osc 119 structure of_ ---. 114-116 Water in j-222=---54s2ssssceee 120 Oklahoma, oil in-_-_---__-_-------- 117 Oregon, enlarged homestead in___-~ 22 Olli so ose oho e eee oe 117 P: Patents, application for, time limit Ones Hee 49 Phosphate lands, area of, still be- longing to United States — 8 classification of, factors in_-. 128-129 principles governing ______ 129-130 regulations for___-_--_-__- 130-1382 diagram illustrating ___-_ 131 distribution of —on-ac