*SCIENTIFIC LITERATURE.*

the reproduction of foliage for groups. The appendix contains addresses of reliable firms from whom tools and materials used in taxidermy may be purchased.

The preparation of this book on *The Storage Battery* was suggested to Mr. Treadwell^{[1]} by his finding a lack in working on these machines of any compact data concerning their construction, and the paucity of reliable discharge curves; and he concluded that a book containing such data and curves, with rules for the handling and maintenance of cells, would be valuable to all interested in storage batteries as well as to the student and manufacturer. Among the points specially mentioned by the author are the lists of American and foreign patents given as footnotes for the various types, not complete but noticing the principal patents for each cell; the chapter on the chemistry of secondary batteries, which gives the latest and most generally accepted theory concerning the chemical reactions taking place in an accumulator, and which has been approved by Dr. Sewal Matheson; and, in the appendix, tables of data comprising figures of all the batteries, methods for the measurement of the E. M. F. and internal resistance of a storage battery; and data from which the theoretical and practical capacity of an accumulator may be determined.

The Natural Advanced Geography^{[2]} is a successful application of modern methods to the teaching of this science, and presents it with the interest undiminished which really appertains to it. While in the elementary book of this, the "natural" series, the pupil starts from his own home and is introduced to the study of man in relation to his environment, in the present work the fact is developed that environment itself is the chief factor in the various activities and economies of man. One of the salient features of the presentation of the subject, marked throughout the work, and one that commands high praise, is the arrangement of the facts into such order that their correlation may be perceived and the unity of Nature recognized. The isolated, barren, curt, unrelated statements that made the study of many of the old geographies hard and tedious are conspicuously absent, and the subject, studied in orderly sequence, "unfolds itself naturally and logically, each lesson preparing the way for those which follow." The first part of the work is devoted to a study of the world as a whole. The second part, comprising about three fourths of the volume, is an application of these laws to the various countries of the globe, beginning with the United States. In the United States, for instance, a general description of the whole is given, which presents a real, comprehensive mental picture of the country; and the process is repeated, in measure according to the conditions, for the several States, so that the pupil is taught what are the factors that give the characteristics and local features to each. A like method is pursued, on a more general scale, with other countries. The colored maps are drawn on a system of uniform scales, with reliefs plainly shown according to the accepted conventions; graphic charts or sketch maps showing the distribution of products and resources are employed; and pedagogical exercises and aids are afforded abundantly.

A text-book on the *Differential and Integral Calculus*^{[3]} for students who have a working knowledge of elementary geometry, algebra, trigonometry, and analytical geometry, by Prof. *P. A. Lambert,* has the threefold object of inspiring confidence, by a logical presentation of principles, in the methods of infinitesimal analysis; of aiding, through numerous problems, in acquiring facility in the use of these methods; and, by applications to problems in physics, engineering, and other branches of mathematics, to show the practical value of the calculus. By a division of the matter according to classes of functions, it is made possible to introduce these applications from the start, and thereby to arouse the interest of the student. By simultaneous treatment of differentiation and integration and the use of trigonometric

- ↑ The Storage Battery. A Practical Treatise on the Construction, Theory, and Use of Secondary Batteries. By Augustus Treadwell. New York: The Macmillan Company. Pp. 257. Price, $1.75.
- ↑ Natural Advanced Geography. By Jacques W. Redway and Russell Hinman. American Book Company. Pp. 100.
- ↑ Differential and Integral Calculus. For Technical Schools and Colleges. By R. A. Lambert. New York: The Macmillan Company. Pp. 245. Price, $1.50.