Page:Popular Science Monthly Volume 36.djvu/431

Rh, appear in another number of this volume. Regarding "The Nature of Knee-jerk," W. P. Lombard maintains that the reflex theory readily explains the intimate dependence of the phenomenon upon the spinal cord, and that the time argument against it is inconclusive, owing to our meager knowledge of reflex times in general, while the peripheral theory is untenable. The third number of this volume is devoted to a paper on "The Relation between the Structure, Function, Distribution, and Origin of the Cranial Nerves; together with a Theory of the Origin of the Nervous System of Vertebrata," by W. H. Gaskell. It is accompanied by five plates. W. D. Halliburton contributes the results of chemical analysis of a number of specimens of cerebro-spinal fluid, and, together with W. M. Friend, the results of an examination of the stromata of the red corpuscles. A second paper on "The Electrical Organ of the Skate," by J. B. Sanderson and Francis Gotch, contains observations as to the nature of the normal reflex process by which the electric organ is discharged, and the measurement of the electromotive force of the response of the organ to a single excitation. J. N. Langley reports further investigations upon the salivary glands in two papers, one dealing with "The Physiology of the Salivary Secretion," the other with "The Histology of the Mucous Salivary Glands, and the Behavior of their Mucous Constituents." L. C. Woolbridge, in a brief paper entitled "The Coagulation Question," argues against certain views of Dr. Halliburton. W. H. White contributes "Further Observations on the Histology and Function of the Mammalian Sympathetic Ganglia," a previous paper having been published in No. 2, Vol. VIII of the "Journal." An extended paper on "The Innervation of the Renal Blood-Vessels," by J. Rose Bradford, deals with the courses of the vaso-constrictor and vaso-dilator fibers, with the phenomena following excitation of the splanchnic nerve and of the peripheral end of the divided vagus, also with the reflex phenomena of the renal vessels. T. W. Shore and H. L. Jones publish a description of "The Structure of the Vertebrate Liver," approaching their subject from the side of comparative anatomy. G. N. Stewart presents a detailed account of a research on "The Stimulation Effects in a Polarized Nerve during and after the Flow of the Polarizing Current." C. S. Sherrington and C. A. Ballance, in a paper on "Formation of Scar-Tissue," give the record of their investigation as to whether the colorless corpuscles of the blood are the source of the new tissue which the inflammatory process produces.

the whole field of sanitary science is brought within a moderate compass in this book. Water, removal of refuse, ventilation, warming, lighting, climate, building-sites, food, exercise, and clothing, all receive due attention from the hygienic side. A chapter on the prevention of communicable diseases has been included, also one on vital statistics. The book is intended for both the physician and the layman. Its language is simple enough, so that no technical knowledge is needed to understand it, though there are some tests and calculations included which the average layman will not make use of for himself. Numerous examples and illustrations are introduced in order to assist the physician in his public health work. The author deems the chapter on the removal of refuse rather long in proportion to the book, but gives as his reason for going so much into detail that apparently trivial defects in house-drainage, which are liable to be overlooked without thorough knowledge, are often the cause of the most severe outbreaks of disease. The volume is lettered on the back, "Practical Hygiene, Parkes," but the intending buyer should not confuse the book with the "Manual of Practical Hygiene" by the late E. A. Parkes.

story of America is told by Mr. Eggleston in this book in a simple and vivid style. The requirements that he has had in view while preparing it are that an elementary book must, for those whose school-life will be short, give the leading facts of the whole field to be studied, and must not force upon those who are to follow it with an advanced work matters which will have to be restudied