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Rh, and to left-handed exceptions, the writing of ancient documents, and the positions of the figures in drawings, bear in the same direction. Consideration of these evidences precludes the idea of the origin of right-handedness lying in any ancient custom, or of its development and enforcement by education into a nearly universal habit. The conclusion is therefore inevitably forced on the inquirer that the bias in which this law originates must be traceable to some specialty of organic structure. This argument becomes stronger when we reflect that right or left handedness is not limited to the hand, but partially affects the lower limbs, as may be seen in foot-ball, skating, the training of opera-dancers, etc., so that eminent anatomists and physiologists have affirmed the existence of a greater development throughout the whole right side of the body. Theories have been proposed assuming stronger circulation, visceral predominance, or more vigorous muscular growth on the right side, but they do not seem to go to the root of the matter; while the theory of cerebral localizations on which many other human faculties have been found to depend seems more ample. It is understood that each hemisphere of the brain affects the opposite side of the body. In the majority of cases where the hemispheres have been weighed separately, the left hemisphere has been found heaviest. This would give predominance to the right Bide In the case of a single left-handed patient, Dr. Wilson and an associated physician found the right hemisphere to weigh the most. "No comprehensive indications can be based on a single case, but its confirmatory value is unmistakable at this stage of the inquiry; and thus far it sustains the conditions previously arrived at."

who are striving against many obstacles to teach science according to its own proper method will be glad of the help which the senior Professor of Chemistry in Harvard College offers them through this volume. It is a manual of directions for experiments in which especial care is taken that what the experiments teach shall not be lost sight of. "The student should be given to understand clearly," says Prof. Cooke in his introduction, "that experiments performed mechanically, without intelligence, or carelessly recorded, are worth absolutely nothing, and should be so estimated in any system of school or college credits." This book is designed as a companion to The New Chemistry, by the same author, which contains no experiments for the student, as the present volume contains no extended statement of chemical principles. The principle that each experiment illustrates, however, is indicated by a heading, and in many cases the conclusions that the teacher should enforce are explicitly stated. Notes, questions, and problems are also inserted after each experiment or group of experiments, in order to direct the student's attention upon the essential features of the investigation in hand. Ample cautions accompany all experiments that would be dangerous if carelessly performed. The present issue of this manual has the value of a revised edition, for the book is an enlargement of a list of experiments printed in pamphlet form that has been used for several years in Harvard College and in a number of fitting schools. In order to make the expense less of an obstacle to the performance of these experiments by school classes, the author has sought to adapt to the purposes of instruction common household utensils, such as may be made by a tinsmith or found at any house-furnishing store. Two figures of a kerosene stove applied to laboratory purposes are given, and many other definite suggestions in regard to apparatus are furnished.

By the publication of Part IV, Dr. Michael Foster, F. R. S., has completed the fifth edition of his Text-book of Physiology (Macmillan, $1.90). This part comprises the conclusion of Book in, on the Central Nervous System and its Instruments, and Book IV, on the Tissues and Mechanisms of Reproduction. There is also an Appendix on The Chemical Basis of the Animal Body. In the portion of Book III here presented the special senses and the voice are briefly treated, and the account of reproduction is also brief. A little more than two hundred pages are given to the topics here enumerated, bringing the whole