[J. F. I.
simplicity of the application is discussed. Among these are some taken from the classic treatise of Laplace with which they are in substantial agreement. The title, which is a bit misleading, is doubtless adapted from that of a chapter in Laplace, " O n the Probability of Causes and Future Events Inferred from Observed Events." The work is a revised reprint of a report in Comptes Re~wlus sponsored by the well-known author of the now widely used Monograms or " Parallel Co6rdinates," M. Maurice d'Ocagne. The method which the author has employed is ingenious, direct, and appealing to the practical user, and is suggestive of further application in clarifying other difficulties in the field of probability. LUCIEN E. PICOLET. PHYSIOLOGICAL AND CLINICAL CHEMISTRY. By William A. Pearson, M.D., Ph.D., Department of Chemistry, Hahnemann Medical College of Philadelphia, and Joseph S. Hepburn, A.M., Ph.D., Associate Professor of Chemistry in Hahnemann Medical College of Philadelphia. 306 pages, ilhistrated, interleaved, small 8vo. Lea and Febiger, Philadelphia and New York, I925. Price, $4. This book, like others that cover the same field, makes a striking contrast to the chemistries offered to medical students in the middle of the last century. American medical colleges then exacted no preliminary educational requirements. The professor of chemistry was obliged to start with the simplest data and build up slowly until he could reach in the closing days of the course a few demonstrations on clinical subjects, almost entirely limited to the tests for urine. It is ungracious to sneer at the sins of commission and omission of our forebears, for they built as wisely as they knew and labored with far more limited means than are now available. Yet one cannot but feel the force of Wurtz's criticism of the old method of teaching organic chemistry, when, as he says, the course began with the sugars and starches, substances about which the 'structural formulas were unknown, proceeded to the study of a group called the vegetable acids, because they have the common property of turning blue litmus red, and later the group called alkaloids because they have the property of turning the red litmus back to blue. The book in hand is a comprehensive and clear summary of the more important tests and procedures as required at the present time in the application of chemistry to clinical problems. The authors have had large experience both in carrying out such work and in teaching the methods to students, and they set forth the results of such work in compact text. The preface informs us that the book covers a course, to which students are admitted after considerable preliminary instruction in chemistry, which is the standard now of all reputable medical schools in this country. In consequence of this preliminary training, chapters on qualitative and quantitative analysis are merely brief summaries of the topics. The interleaving allows of note-taking by the student and also of any corrections or of changes in detail of methods as are constantly appearing in periodical literature. The reviewer is compelled to express disapproval of the long list of titles attached to each author's name. Both the authors are quite well known as excellent chemists; their "degrees and the fact that they are occupying responsible positions in a first-class medical school will be sufficient recommendation
if any is needed. Membership, for instance, in the American Chemical Society is proper, but as a matter of fact it is no professional recommendation for the door to it is wide open. The student in physiologic and clinical chemistry will find in this book all the important information on the subject. On one point the reviewer questions the appropriateness of the test chosen, namely, in the detection of methanol. The old copper spiral method is given. The test by oxidation with permanganate, with the modification suggested by La\Vall, now official in U.S.P.X, should have been described. HENRY LEFFMANN. A TEXTBOOK OF GLASS TECHNOLOGY. By E. W. Hodkin, B.S., A.I.C., and A. Cousen, M.S., A.R.C.S., A.I.C. W i t h a foreword by Professor Turner, of the Department of Glass Technology, University of Sheffield. xxiii-55I pages, 25I illustrations, 8vo. New york, D. Van Nostrand Company, 1925. Price, $I2 net. It cannot be said of this book that the industry to which it is devoted is seen " through a glass darkly," for it is a most explicit and comprehensive presentation of the whole field of glass manufacture, theory as well as practice being discussed. One gets from it an impressive idea of the importance of glass in human affairs. In the foreword by Professor Turner, it is stated that works in English on the subject are few. Books on stained glass and manuals for collectors are not lacking. Such books, indeed, timJ large sale; publishers are not afraid to make great outlay in the printing of them, for those who buy are accustomed to paying high prices for what they wish, but a work on the technology of glass appeals to an entirely different public. Much credit is due the publisher for the excellent manner in which the book has been got up, many of the photogravures being most commendable in clearness and brilliancy. Especially commendable is the plate facing page 5, showing several fine pieces of clear glassware made in England in the first half of the eighteenth century. The authors give as an introduction a highly interesting account of the development of glass-making from the earliest known state to the present. The story told in classical history of the accidental discovery of the method of making glass is not now looked upon with favor. The earliest definite manufacture is assigned to Egypt. According to Petrie, this manufacture in Egypt, as distinct from the glazing of pottery, dates about 35oo years ago. The glass factories of Alexandria became famous. Phenician traders probably carried the products to many parts of the Mediterranean borderlands. Rome received much glass from Alexandria, but about the beginning of the present era, Egyptian glass,workers found their way to the Eternal City and in the first quarter of the third century of the era, Alexander Severus found the industry so well developed that he levied a special tax on it. The separation which then existed between the scientists and philosophers, on the one hand, and artisans and tradesmen on the other, prevented the co6peration of theory and practice that is so characteristic of the present age. American readers and students will be interested in the note of the development of the glass industry in the Western Hemisphere. This, it appears, was a :factory for the manufacture of window glass, established in I79O, by Robert Hewes in New Ham, pshire. It was not successful and the industry languished