Page:Popular Science Monthly Volume 44.djvu/871

Rh and preserved five hundred species of plants, and laid the foundation for a thorough acquaintance with botany. He was next placed with a country surgeon, and here undertook by himself the study of comparative anatomy, dissecting animals and birds, and executing drawings of marvelous exactness and beauty. It may well be credited that at fifty years of age he had produced more original work than any other English anatomist. His zest for knowledge and keen enjoyment of Nature never waned. At sixty-five he writes: "The sight of the wild flowers, the settling of a speckled, metallic feathered starling close to me, and the song of the lark made weariness a trifle; . . . the joy of research has been the wine of my life." A characteristic portrait is the frontispiece to the memoir, and a list of published works is given at the close, these being mainly upon the foraminif era, the vertebrate skeleton, and skull.

volume constitutes the third edition, enlarged and revised, of a former work, the Principles of Hygiene, by the same author.

The subject is treated in four main divisions—health of the man, health of the house, health of the city, and health of the people. In addition to these there are chapters on demography, meteorology, and sanitary law.

Much space is given to the section on dietetics, where somewhat of the changes involved in nutrition are explained according to the experiments of Pettenkofer and Voigt. The prevalent error is noted of confounding oxidation with metabolic processes in the body. The value of a food depends upon the ease with which it digests, splits up, and combines in the organism, not upon the constituents per se.

Common snares are also pointed out in the food that does not nourish, the filter that is worse than useless, the barometer which measures nothing, the disinfection that does not disinfect, and the statistics that prove a trap for the unwary. But the effort of the book is mostly constructive, and there is much in it that is valuable for the student of statistics and the householder. The unfortunate schoolgirl may, if it falls into her hands, drop it with righteous scorn. The chapter on school hygiene is disfigured by a thrust at feminine ability and the threadbare plea that woman's health suffers in the educative process. The author, illogical enough, gives the best possible reply to this in his dissertation on exercise, where he informs us that most of the ailments of women would be prevented if girls strengthened their muscles as their brothers do!

The Child, Physically and Mentally, is considered by Bertha Meyer in a small pamphlet translated from the German by Friederike Salomon and published by the M. L. Holbrook Co. A similar work was written by the author thirteen years ago, and this is intended as a supplement, embodying the more recent teaching of hygienic science. It is curious to note that it contains only two pages of suggestion for the mother who desires to rear her child in the natural way. This is certainly not all that should be said on the subject in a country where infant mortality is exceptionally high. An appendix is needed to justify the aim and title of the brochure.

The Arithmetic of Magnetism and Electricity, by John T. Morrow and Thorhurn Reid, a little handbook of 145 pages, consists of the statement and explanation of those facts and laws of electricity and magnetism which are especially connected with their practical and commercial aspects. It contains among other matters chapters on General Laws of Electric Circuits; Batteries, Primary and Secondary; Direct-current Dynamos and Motors; Alternating current Dynamos, Motors, and Transformers; Lighting and Power, and The Application of Electrical Laws to Electrical Railways; with some useful tables. (It is published by the Bubier Publishing Company, of Lynn., Mass., at $1.)

A System of Analysis of Milk and MUk Products, containing results of the latest researches, is given us by Leffmann and Beam. Most of the earlier processes have been superseded or at least greatly modified in the past few years by the large amount of original work done, more especially under the supervision of the Society of Public Analysts. The book is intended not only for professional chemists, but also for practical dairymen, and to such it ought to prove