National Geographic : 1898 Jul
342 THE GEOLOGIC ATLAS OF THE UNITED STATES / by a summary account of the geography, including climate and vegetation, agriculture, etc. Next follows an account of the gen eral geology, including a history of physical changes, set forth verbally and graphically. In this division of the work the char acteristics of the formations are described, the sources of materials are considered, the subsequent alterations recorded in texture and structure are investigated, and the great orogenic and epeiro genic movements that produced the majestic Rocky mountains and (especially) the broad plains at their base are interpreted i. e., the phenomena are treated both locally and comparatively, and in remarkably luminous and attractive fashion. The for mations range from recent alluvium through earlier Pleistocene, Neocene, Cretaceous, Juratrian, Carboniferous, and Silurian to the Archean nucleus exposed in the ranges; and there were sev eral periods of deformation, the movements of which have been analyzed and clearly set forth. In describing the formations and discussing the deformations full recognition is given to the principles of geomorphy and to homogenic correlation, and the history of the tract is thereby made clear and definite. There is a final chapter on economic geology in which the resources, including phreatic water, are fully described. This synopsis merely indicates the scope of a notable publica tion; it does not and cannot give any adequate idea of the high scientific and educational value of a great work which can be properly appreciated only after examination. It is not too much to say that this atlas folio by itself would, in the hands of a com petent teacher, serve as a complete introduction to geology, by means of which any pupil might gain an elementary knowledge of the science; or that in the hands of a competent teacher (or, indeed, of an intelligent student without a teacher) within the tract described the work would be more serviceable than any manual or text-book of geology ever written. The publication of these atlas-folios representing particular tracts in all parts of the country is bound to revolutionize geologic teaching quickly, completely, and permanently. WJM. AT the annual meeting of the Royal Geographical Society, held recently in London, the Founders' Medal of the Society was conferred on Dr Sven Hedin for his explorations in Central Asia, and the Patrons' Medal on Lieut. Robert E. Peary, U. S. N., for his work in Greenland.