x6 



SCIENCE. 



[Vol. XXI. No. 519 



isfactory classification of rocks and a satisfactory system of map- 

 ping. These conditions, in connection with the conditions grow- 

 ing out of the changes in the organic law of the bureau, have 

 determined the character and progress of work in the Geological 

 Survey. 



The work of collecting mineral resources has been steadily car- 

 ried forward, and it has been found thereby that the mmeral pro- 

 duction of the country has more than doubled within the thirteen 

 years since the institution of the Survey, and that many new re- 

 sources have been discovered and utilized. The statistics are 

 collected with care by means of an elaborate system of corres- 

 pondence and collaboration, and are pulilished in a series of an- 

 nual volumes. The annual mining product of the country has 

 now reached the value of six hundred and fifty million dollars. 

 The products form the basis for many of our industries and a large 

 proportion of our commodities, and give employment to a great 

 part of our population. Thus a principal source of our national 

 prosperity is made public and rendered available for further de- 

 velopment through this part of the work of the Geological Sur- 

 vey. 



At first the art of topographic surveying was imperfect and the 

 work was slow and expensive. Accordingly, experiments were 

 conducted in different types of country, with different kinds of 

 apparatus, and with different men and methods ; and. after deter- 

 mining the best methods and apparatus for each part of the coun- 

 try, a corps of topographers was trained. This experimental 

 stage of the work lasted four or five years, though the experiments 

 were so conducted as to yield useful results which are incorporated 

 in the atlas-sheets representing the general topogi'aphic survey. 

 Some of the earlier sheets were, however, found defective, and in 

 these cases the experimental surveys were repeated and the sheets 

 revised. The topographic surveys have how been completed over 

 an area of about six hundred thousand square miles, or about 

 one-fifth of the national domain, exclusive of Alaska. The total 

 cost, including experimental work and an extensive plant, has 

 ranged from one dollar to fourteen dollars per square mile, aver- 

 aging about four dollars. Thus it is believed that the surveys of 

 the bureau have been more expeditious and less expensive than 

 any other topographic surveys of equal accuracy thus far made 

 in any country. The work is not geodetic, nor is it cadastral ; 

 yet, while it is primarily designed only as a basis for the geologic 

 surveys and thus for the geologic map contemplated in the statute, 

 the atlas sheets have been found useful for many other purposes. 

 They are in constant demand by engineers, road commissioners, 

 miners, and prospectors, and are widely accepted as the most 

 useful bases for mining and commercial maps and school and gen- 

 eral atlases. 



When the geologic studies were commenced much of the na- 

 tional domain had never been examined by geologists, and thus 

 the rock formations and mineral deposits of the country were not 

 classified ; moreover, there was no comprehensive plan for geo- 

 logic mapping. Accordingly, in geology as in topography, the 

 initial stage of the work was preparatory and was designed to 

 develop, first, a system of classification of rocks, and, second, a 

 system of mapping them. But, while the work was experimental, 

 it was conducted in accordance with the best systems of classifi- 

 cation and mapping already in vogue in this and other countries, 

 and was thus made to yield useful results which are published in 

 preliminary maps and reports. Thtse preliminary results of the 

 work are incorporated in thirteen royal octavo annual reports (of 

 which the last three are about to leave the press), twenty quarto 

 monographs, and one hundred octavo bulletins, in adaition to seven 

 octavo volumes of the reports of mineral resources. 



By reason of the immaturity of the science, and by reason of 

 the vast extent and complexity of the rocks of the country, the 

 preliminary stage in this work was longer than in topography, 

 lasting indeed ten or twelve years. Within the last two years the 

 classification of rocks, mineral deposits, and superficial forma- 

 tions has been so far elaborated as to warrant use as a basis for 

 the geologic map of the United States; and, at the same time, a 

 system of mapping has been developed. Under this system pro- 

 vision is made for representing the sedimentary, igneous, and 

 ancient crystalline formations, as well as the mineral deposits 



associated with each, by distinct conventions; and provision is 

 made also for mapping the superficial formations on separate 

 sheets in those regions in which they are well developed and of 

 economic or scientific importance. This system of mapping has 

 been under actual trial for two years, and is now practically ap- 

 plied. Over a dozen sheets have been engraved in the office of 

 the Survey within the past year, and several others have been 

 published or are in press, appended to reports on special regions 

 or topics; and a still larger number are completed in manuscript. 

 One hundred atlas-sheets representing rock formations and min- 

 eral deposits, each constituting a section of the final map, are en- 

 graved or ready for engraving; and these sheets cover an area 

 of about 120,000 square miles, or four per cent of the national 

 domain, exclusive of Alaska. Moreover, sixty atlas-sheets show- 

 ing superficial formations have been completed in regions in 

 which the underlying rocks are generally inaccessible and of little 

 economic value, and these sheets cover an additional area of 

 about 60,000 square miles. Thus the aggregate area now mapped 

 geologically reaches 1«0,000 square miles, or six per cent of the 

 national domain. 



In addition to the areal surveys, important results have flowed 

 from the researches conducted by the Geological Survey. These 

 results are not easily stated, partly because science is not quanti- 

 tative and cannot be weighed and measured in any standard units, 

 partly because science is common property and some portion of 

 each great result is to be credited to scientific investigators not 

 connected with the bureau. Nevertheless, a number of valuable 

 additions to the science of geology have been made during the 

 past decade, largely through the labors of the able corps of ex- 

 perts, to whose skill, zeal, and industry the bureau owes much of 

 its success. Among these may be mentioned, the recognition and 

 founding of a great rock system, the Algonkian ; the discrimina- 

 tion of glacial deposits throughout northern United States and the 

 interpretation of the complex and wonderfully interesting history 

 of which they are records ; the discovery of the rate of seismic 

 transmission and of other laws of earthquakes ; a classification of 

 the igneous rocks and a tentative grouping of the ancient crystal- 

 lines ; the development of a new division of geologic science — 

 Geomorphy, or the New Geology — in which the past history of the 

 earth is read from topographic forms, as formerly from formations 

 and their fossils ; and a general physical classification of the rocks 

 of a considerable portion of the country. 



The cost of the areal geologic work has ranged from less than a 

 dollar per square mile in provinces of simple structure to fifty or 

 sixty dollars per square mile in certain mining regions of excep- 

 tionally complex structure. The average cost, making reasonable 

 allowance for reconnaissance, and reckoned on the basis of aggre- 

 gate appropriations, is eight or nine dollars per square mile. It 

 is to be noted that this figure includes all collateral work in 

 paleontology, chemistry and physics, mineral resources, engrav- 

 ing, and miscellaneous work of all kinds,, as well as the acquisition 

 of a large library, the publication of one hundred and forty re- 

 ports, the training of experts, and the purchase and maintenance 

 of an extensive plant, together with a general reconnaissance of 

 the country. The actual cost of the geologic surveys in two 

 representative provinces, including field and office work as well 

 as supervision and revision, ranges from two to three dollars per 

 square mile. Accordingly, although the geologic work is barely 

 past the experimental stage, the cost compares favorably with 

 that of similar work executed in foreign countries and in our own 

 States. 



Future Work. 



It is believed that the organization of the work of collecting 

 and publishing mineral statistics is now so complete and the corps 

 of correspondents and other collaborators so expert and zealous 

 that this branch of the work may be carried forward more expe- 

 ditiously and economically than ever before. It is the design not 

 only to continue but gradually to expand this branch of the 

 work, in order that it may keep pace with the increasing develop- 

 ment of mining production, the discovery of new mineral re- 

 sources, and the invention of neve applications for resources al- 

 ready known. 



