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Rh which, under the ordinary plan of awaiting a complete survey of the region, would be delayed for years. Following this report are papers on The Dinosaurs of North America, by O. C. Marsh; Glacier Bay and its Glaciers, by H. F. Reid; Some Analogies in the Lower Cretaceous of Eu-rope and America, by L. F. Ward; Structural Details in the Green Mountain Region and in Eastern New York, by T. N. Dale; and one of three hundred pages on Principles of Pre-Cambrian North American Geology, by C. R. Van Hise. All of these are adequately illustrated, that of Prof. Marsh having eighty-five plates. The second volume is devoted to papers of an economic character, an account of the Geology and Mining Industries of the Cripple Creek District, Colorado, having first place. The general geology of the district is set forth by Whitman Cross in considerable detail. The plan followed involves giving the character of the various rock formations, the evidences of action by the ancient Cripple Creek volcano, and descriptions of the rocks forming each of the hills in the camp and vicinity. R. A. F. Penrose, Jr., describes the mining geology of the district, telling what ores are met with, how they occur, and the way in which they were deposited. He also gives detailed descriptions of the ore deposits of the various hills and gulches, and frequently describes the veins followed by individual mines. Prof. N. S. Shaler contributes a paper on the Geology of the Road-building Stones of Massachusetts, giving the results of tests made on a considerable variety of stones, with some discussion of the value of the different kinds under various practical conditions. The Economic Geology of the Mercur Mining District, Utah, is treated by J. E. Spurr. There are two monographs bearing on irrigation: The Public Lands and their Water Supply, by Frederick H. Newell, and Water Resources of a Portion of the Great Plains, by Robert Hay. The former of these papers tells the character of the remaining public lands and in what States they are located, and gives the available sources of water in each State. The latter gives the results of an investigation on a strip of country lying along the eastern boundary of Colorado, this district being chosen as typical of the Great Plains region. The volume is adequately illustrated with maps, diagrams, photographic views, etc. The report on the Mineral Resources of the United States, with which the name of David T. Day has been for many years identified, appears for 1894 in a new form. It constitutes the third and fourth of the royal octavo volumes of the general Report of the Survey. Mr. Day has utilized the greatly increased space allowed him by producing a much more valuable work in his field than ever before. Iron is the first of the minerals to be considered, and in addition to the statistics for the United States there is an account of the production of iron ores in various parts of the world, by John Birkinbine, and a statement of the operations of the iron and steel industries in all countries, by James M. Swank. Other metals are treated by various specialists or by the editor. The second of Mr. Day's volumes is devoted to non-metallic products. Here the account of coal production, by Edward P. Parker, has first place. The manufacture of coke and the production of petroleum and natural gas are presented by Joseph D. Weeks. William C. Day tells of the year's operations in the stone industry, Heinrich Ries contributes an account of the technology of the clay industry, while minor products are treated by various hands. The first appearance of monazite in these reports is made the occasion for a historical and chemical account of the substance by H. B. C. Nitze. This is the mineral used in making incandescent mantles for gas-burners.

The idea that it is well to become acquainted with the beings that they are to do their professional work upon has now taken firm hold upon the teachers of this country. They are absorbing the many books on the psychology of children that are offered to them and demanding other treatises on special topics not yet fully or clearly dealt with. A volume that undertakes the inconspicuous but fundamental task of supplying facts from which the characteristics of children may be learned is the collection of Child Observations made by students of the State Normal School at Worcester, Mass., and edited by Miss Ellen M. Haskell (Heath, $1.50). The twelve hundred examples of children's doings here presented are purposely confined