Page:Popular Science Monthly Volume 46.djvu/870

 instruments and practice in manipulation that he is ready at the start to investigate the operation of electrical apparatus." The following titles of experiments will give an idea of the sort of problems proposed: Comparison of magnetization curves of dynamos, characteristics of the Waterhouse dynamo and study of third-brush regulation, calibrating a voltmeter, effects of speed variation with a series dynamo, photometry of the arc light, specific heat of a liquid, influence of temperature upon the color of pigments, spectrophotometry, exploration of the earth's magnetic field. In preparing this volume. Prof. Nichols has had the cooperation of Messrs. George S. Moler, Frederick Bedell, Homer J. Hotchkiss, and Charles P. Matthews.

is a touch of irony in the preface to this volume that is too good to be lost. The author observes, "If science is to be taken seriously, it rather seems desirable that those who study it should have to use their brains as much as in learning Euclid, algebra, or grammar."

Although it is often urged in behalf of scientific study that its disciplinary effect equals that of drill in the classics, the notion is wonderfully prevalent, even in this country, that a knowledge of science may be imbibed in a haphazard fashion without much application.

A little investigation of such a book as this will tend to convince the aspirant for mental exercise that as much of it is involved in becoming precisely acquainted with one flower as in mastering a chapter in Greek.

With the exception of a dissertation on the physiology of nutrition and an introduction explaining simple botanical terms and divisions, the whole volume is devoted to a consideration of three floral types, the Wallflower, the White Lily, and the Spruce Fir. These higher plants are chosen, not only because they are familiar forms, but also since they exemplify the division of labor and give an opportunity to become acquainted with the more specialized organs and their functions. The vegetative and reproductive organization of each, their external characters and internal structure, are minutely described. The phenomena of pollination, fertilization, the chemistry of the nutritive process and protoplasmic movements, are traced out in like fashion and the mysteries of plant life unfolded.

In method, arrangement, and language the book is altogether commendable. It is also well illustrated and contains an index. The addition of a glossary might be suggested, as likely to prove convenient to the young student.

volume is the second of a series, the first of which appeared in 1890. Like its predecessor, it does not include the general course of lectures given at Wood's Hole pertaining to the work pursued, but indicates special lines of inquiry involving unsettled problems.

Necessarily different points of view are developed, and the reader can test whether he believes fully in the cellular theory as expounded in The Nature of Cell Organization or in its inadequacy as presented by Prof. Whitman, who quotes from Huxley's essay of 1853 that the cells are no more producers of vital phenomena than shells on the sea beach, marking only where vital tides have been.

A valuable and interesting paper also is that on physiological morphology, in which the author, Jacques Loeb, maintains that all life phenomena are determined by chemical processes.

On the other hand, in Dynamics in Evolution, we learn that natural selection is a mischievous metaphor; that morphologists and physiologists are on the wrong track and can not settle the greater questions in biology. Surface tension is the important factor in the shaping of the cell, and the changes in amœboid form are understood only by dynamical analysis. No progress can be made in regard to the meaning of life until speculation about germ plasm or a lot of biophores, plastidules, et sic, superintending the business of development is abandoned.

Two popular and attractive essays are