Page:Popular Science Monthly Volume 46.djvu/434

420 and Relations of Physical and Psychical Phenomena. In the first of these he shows how each property of matter could be regarded as a manifestation of energy; in the second he points out the bearing of certain principles of physics upon the probability of various claims of the spiritists and theosophists, while in the third he argues that whatever wonderful things really take place at séances are done in conformity with the laws of matter, not in opposition to them.

In the mathematical series for graded schools, by John H. Walsh, Part II, or Intermediate Arithmetic, comprises Chapters VI to X. The subjects taken up are fractions, decimals, denominate numbers, bills, measurements, and, in the last chapter, algebraic equations. Part III, or Higher Arithmetic, completing the series, comprises Chapters XI to XVI, dealing with the various subjects involving percentage computations, with proportion, square root, mensuration, and the metric system. There is also a chapter on algebraic equations and one on elementary constructive geometry. As special features of the series, the author calls attention to its division into half-yearly chapters, instead of by topics, the small number of rules and definitions, the great number and variety of examples, and the use of the equation. (Heath, Part II, 40 cents; Part III, 75 cents.)

The Complete Graded Arithmetic, prepared by George E. Atwood, begins with a Part I, in which the usual elementary work with integers and the manipulation of fractions are taught. It provides work for two years of three terms each. The author has aimed to incorporate enough review work in each lesson so that the teacher shall not need to do any planning of reviews. The rules and definitions are put at the end of the book and referred to by number. Part II provides exercises for three years, passing from elementary decimals through denominate numbers, the various commercial calculations involving percentage, and ending with mensuration. The making of bills, receipts, notes, drafts, etc., is a feature of the examples. (Heath, Part I, 45 cents; Part II, 85 cents.)

Any one who wishes to know what Modern Theosophy is will find an attempt to tell him in a book with the above title, by Claude Falls Wright (New England Theosophical Corporation, 24 Mount Vernon Street, Boston, $1). To the strict adherent of modern scientific thought the book will be meaningless, for it is full of assertions unsupported by anything that he is accustomed to regard as evidence—conflicting, in fact, with many things that are so supported. Perhaps not entirely meaningless, for it may serve as an instructive example of the vagaries that the human mind is capable of when not forced to occupy itself with something useful or reasonable.

An Introduction to the Mathematical Theory of the Stress and Strain of Elastic Solids has been prepared by Benjamin Williamson, a Fellow of Trinity College, Dublin (Longmans, $1.50). The book is small, but its author hopes that "it is sufficient to enable the student to understand the mathematical theory of the internal strains and stresses that arise whenever external forces are applied to solid bodies." The rapid increase in the size of the structures that modern engineers are undertaking makes a thorough understanding of the distribution of stress extremely important.

In The Science of Vital Force, by W. R. Dunham, M. D. (Damrell), the idea that the author talks about and around seems to be that medicine has no active property, but that disease is cured by vital activity.

Captain Willard Glazier has published another book in support of his claim to have discovered the real source of the Mississippi River (Rand, McNally & Co.). It is entitled Headwaters of the Mississippi, and describes the adventures of explorers of that river from De Vaca, in 1528, down to the present time. Captain Glazier's expedition which resulted in his discovery of Lake Glazier was made in 1881, and, as the importance of this lake became a matter of controversy, he made a second expedition in 1891, to obtain more convincing proof of his assertions. The story of his second expedition forms the latter part of this volume, and is followed by an appendix of letters and other documents in support of Captain Glazier's position. The volume contains a great deal of descriptive matter concerning persons and places in Minnesota, and is fully illustrated.

The little book on Gas-lighting and Gas-fitting, by William Paul Gerhard (Van Nostrand, 50 cents), contains specifications and