certain the position of the sun in the Galactic Cluster, this volume of the "Annals" fills a place which no other work yet published can make any pretense to. Whether we consider the perfection of the instrument employed, the plan of observation pursued, the accuracy and care with which the observations were made, the large number of stars observed, the completeness of the records, or the exhaustive comparisons that have been made of the observations with those of other astronomers, we are equally satisfied that, so far as the photometric observation of all stars visible to the naked eye in northern latitudes is concerned, the work of Professor Pickering and his able assistants leaves nothing to be desired.
The Chemistry of Cookery. By W. Mattieu Williams. New York: D. Appleton & Co. Pp. 328. Price, $1.50.
Since the publication of Johnston's "Chemistry of Common Life," thirty years ago, no book so important has appeared in this line of inquiry as the volume before us. Johnston's work was of broader scope, and, in fact, contributed little to the science of the culinary preparation of foods, to which Williams's work is devoted. Much has been done in this direction in the last generation, and a work was needed embodying the most important practical results. This Professor Williams has now given us in a very satisfactory form. Of the extent and importance of the information conveyed in his pages nothing need be said to the readers of "The Popular Science Monthly," in which the successive articles have appeared; but, now that they are collected together and offered as a treatise on the science of cookery, it is proper to state that the work has been ably done, and is entitled to rank as a standard upon its subject. Mr. Williams has given us "the present state of knowledge" on the chemical changes to which alimentary substances are subjected by customary kitchen operations. His facts and his chemistry are to be relied upon, and his conclusions are generally made with judgment, but some of his speculations may be extreme, and will be received with caution. His work has been criticised as if he had made too much of the test-tube and analytical operations, and built unwarrantably upon their results. There are, of course, many things about organic substances and their subtile changes which chemistry can not explain, and it certainly can not give us a complete science of foods. But the author of the present work is quite aware of this, and we do not think he has unduly strained the resources of his science in his efforts to elucidate the subject. His book will prove invaluable to read, for practical instruction, for reference in using common cook-books, and as a text-book for classes wishing to study the science of cooking in a careful and thorough manner.
A Text-Book of Hygiene. By George H. Rohé, M. D., Professor of Hygiene, College of Physicians and Surgeons, Baltimore. Baltimore: Thomas & Evans. Pp. 324.
Every important division of the subject receives some attention in this treatise. It is intended to present the essential facts upon which the art of preventive medicine is based, in such manner as to form a guide for the American student, practitioner, and sanitary officer. Beginning with general considerations in regard to air, water, food, and soil, the author goes on to the special hygiene of dwellings, hospitals, and schools, and takes up also industrial, military, marine, and prison hygiene. Several chapters are devoted to personal hygiene. Histories of the epidemic diseases are given, and the subjects of disinfectants, quarantine, and vital statistics are also included. A list of special works is given with each chapter. The author makes little claim to originality; the qualities which he has especially sought are comprehensiveness and reliability.
The Microtomist's Vade-Mecum. By Arthur Bolles Lee. Philadelphia: P. Blakiston, Son & Co. Pp. 424. Price, $3.
This work—"a hand-book of the methods of microscopic anatomy"—has been prepared chiefly with the design of furnishing a complete but concise account of all the methods of preparation that have been recommended as useful for the purposes of microscopic anatomy. In order to make it also a suitable guide for beginners, a general introduction has been added, and introductory paragraphs have been prefixed, when needful, to the different chapters,
