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276 of one species to another that is better endowed with means of defense, or with some other desirable possession. Mr. Beddard frequently cautions investigators against proceeding as if the sight or taste of animals were the same as that of man, for in the questions here discussed the point of view is important. The volume closes with an account of the chief differences in coloration between the sexes of animals, and a statement of the leading theories proposed to explain them. The text is illustrated with four colored plates and thirty-six woodcuts.

is rapidly acquiring the means for teaching its great pedagogical lesson that most knowledge may be obtained better from the study of things than from the study of books. This little manual is such a means. The first part of it is adapted to children of the usual primary-school age, and the second part to those in grammar-school grades. Its method requires constant practice in observation and investigation upon the objects and processes studied or upon pictures of them, thus giving the child at the outset of his education a thorough grounding in the natural way of acquiring knowledge. Prang's Lithographs of the Trades and Mr. Calkins's Manual accompanying them are expected to be used where the actual operations can not be witnessed.

The presidential addresses delivered before the Philosophical Society in 1888, 1889, and 1890, together with thirteen papers on special scientific topics, form the body of this volume. With these are printed the minutes of the society and of the Mathematical Section for 1888 to 1891, the rules and lists of officers and members of the society. Among the papers is one on The Observation of Sudden Phenomena, by Prof. S. P. Langley, in which is described a mechanism for lessening the error in observation represented by the "personal equation." Prof. F. W. Clarke has a paper on The Relative Abundance of the Chemical Elements; another is by Everett Hayden on Hurricanes in the Bay of North America; and John R. Eastman has a record of The Progress of Meteoric Astronomy in America, containing important catalogues of meteorites and meteoric showers. As the subject of his presidential address in 1891, Major Clarence E. Dutton took the practical matter of Money Fallacies. The Evolution of Serials published by Scientific Societies is traced by W J McGee. The other papers deal with various technical matters.

practical and commercial side of phosphate mining occupies almost the whole of this volume, although it is supplemented by some notes on the geology of phosphate deposits and numerous tables of chemical analyses. The raising of phosphates from the beds of streams, the mining of pebble-deposits and of rock phosphates are described briefly, and copious information is given in regard to transportation, freights, prices, cost of production, companies engaged in the business, and similar matters connected with the industry. About half the volume is devoted to the Florida operations, South Carolina and Canada dividing the other half between them. An appendix contains analyses of a variety of foreign phosphates.

Under the title Cardiac Outlines a manual for physicians has been prepared by William Ewart, M. D. (Putnams). It is devoted to the physical examination of the heart and the recording of the results of such examination. The mode of recording the observations advised is by means of diagrams, in various parts of which are arrows to be crossed out if the sounds for which they stand are absent. There are fifty-two figures, and several leaves bearing the diagram referred to are bound into the volume.

A handsome manual of directions for Leather Work has been prepared by Charles G. Leland, whose manuals on several other minor arts are well known (Macmillan & Co. $1.50). It is eminently practical, beginning with a description of tools and materials and