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Rh abundantly proving his position, and shows very clearly that, so far from the workingman profiting by protection, he is injured at every turn. It is much to be hoped that the essential contention of the book can be properly brought before the farmers and artisans of the country while attention is so keenly alive to the importance of tariff questions. Tariff reformers will find ready to their hand in its pages just the kind of material needed to illustrate and enforce their positions, and should make good use of it in the opportunities afforded by present political discussions.

original volume under this title issued some twenty years ago has gradually grown in size by the addition of new papers until it finally became so unwieldy as to necessitate dividing it into two volumes. Besides the matter in the previous edition there are some fifteen new papers, mostly relating to researches in molecular physics. The present volume and the volume recently issued under the title of New Fragments contain, the publishers state in an introductory note, all of the occasional papers which Prof. Tyndall cares to preserve in a permanent form. The first of the present volumes contains the papers that relate to the laws and phenomena of matter solely; while the second, with the exception of the address upon the electric light, deals with questions which traverse the domain of mind as well as of matter. This volume contains the celebrated Belfast address delivered before the British Association at its Belfast meeting in 1874, as well as Prof. Tyndall's reply to various critics which he issued under the title of An Apology. The volume contains also the well-known address upon the Scientific Use of the Imagination, and that upon Matter and Force, as well as his excursion into fields considered by theologians especially their own, in which he discusses miracles and prayer in relation to natural laws.

It is not necessary at this late day to say anything in commendation of Prof. Tyndall's exposition of science. He is read wherever the English language is spoken, and comes perhaps in closer intellectual and emotional contact with his readers than any other scientific man of our time. This is due in large measure to that transparent intellectual honesty which makes him scorn to be self-deceived or to take any lower aim than the pursuit of truth, lead whither it will. There is, moreover, an elevation of moral tone pervading all his speculations concerning that unknown world into which we vainly peer, which brings him into sympathetic contact with all earnest seekers after truth, no matter how widely they differ in their conclusions. Of the literary merit of the discourses of Prof. Tyndall it is also needless to speak. The purity and vigor of his diction have always charmed his readers as much as his lucidity of thought, and he has long been recognized as one of the masters of style. Those who prize his writings will be glad to have them in this last form, which in all probability will prove to be a final one.

This little book consists of a course of six lectures delivered before a juvenile audience at the Royal Institution, and is an excellent example of what a popular exposition of a scientific subject should be. Though addressed to juveniles, the lectures can be read with interest and profit by older folk who are not specially informed on physiological subjects and the methods and apparatus used by experimenters in studying the problems to which they address themselves.

The title Prof. McKendrick has given to his course is not a very happy one, as it does not indicate with any clearness the subject-matter of the lectures, which deal with muscular movement. He uses in his demonstrations the muscle of the frog which correponds with that of the calf of the leg in man. This he excites by means of an electric current, and performs a number of the striking and beautiful experiments devised by physiological experimenters for the study of the behavior of living matter. He illustrates by experiment the lifting power of a muscle when contracting; the nature of the movement that occurs when a muscle is contracting; shows graphically by means of curves on smoked glass the times of contract-