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are two methods of chemical analysis, when the operation is carried to its highest result for the purpose of establishing quantities in chemical composition. The first, and older method, is that by weighing; it involves the use of the balance, and is called the gravimetric method. The second, and newer mode, is by measurement of bulk; instead of the balance, it employs the burette, a graduated glass tube, and it is called the volumetric method. There are certain advantages in the newer process which are becoming more marked as it is more practised and developed. The superiority claimed is greater simplification and quickness of operation, with an equal and sometimes a greater degree of accuracy. Dr. Fleischer's treatise has been translated into English because it is a systematic work upon the subject, accepted as a standard in Germany, and believed to be much better for students than any original contribution to the subject in our own language. The present transitional state of chemical science, in regard to theories and the modes of expression that follow them, is well illustrated by the fact that the author of the book adopts the old notation, while his translator adopts the new. The consequence is, that both methods are given, which is a good feature of the work, and the translator thinks that the putting of the two notations, side by side, will be useful as disclosing the superiority of the newer plan.

precise nature of this author's "philosophic ideas" may be inferred from his highly-satisfactory explanation of Newton's law of gravitation. "Why," he asks, "does matter tend to approach other matter, and why should it approach with constantly accelerating speed?" And his answer is: "This action is the necessary outflow of the deific attributes essential to matter. Its love and intelligence are shown in approximating, so that it can mutually impart and receive more of each other's beautiful and pleasing varieties of motion by sympathetic action." And so on.

the report of additions made to the museum and library in 1876, which were large and valuable, this volume contains reports of explorations in American archaeology, made by Dr. Charles C. Abbott, Prof. N. S. Shaler, Prof. E. B. Andrews, and Lucien Carr, Assistant Curator; also, an elaborate paper, by Ad. F. Bandelier, "On the Art of War and Mode of Warfare of the Ancient Mexicans."

Dr. Abbott's report is specially interesting, as containing an account of his discoveries of rude stone implements in the drift gravels of the Atlantic border in New Jersey. These implements were found at various depths, mingled with the gravels, near Trenton and along the banks of the Delaware. In the opinion of both Dr. Abbott and Prof. Shaler these gravels are of glacial origin, and the implements obtained were wrought by man, who inhabited the region at the close of the ice age, or during interglacial periods, where the climate favored their existence.

This is in striking accord with the previously-expressed views of Prof. Grote, who, in a paper read at the Detroit meeting of the American Association in 1875, and later in an address entitled "Early Man in North America," published in this Journal for March, 1877, takes the ground that man lived here during the glacial period. In this address, alluding to the implements discovered by Dr. Abbott, he says: "To me it seems clear that the men who used these rough tools dwelt on the edge of the glacier, and their implements have become buried in the moraines which were forming at many different points during the ice period."

reputation as an original investigator will secure for this paper careful attention. It was first published in the American Journal of Medical Sciences for April, 1877, being a study of a case of traumatic neuralgia, considered especially in its relations to atmospheric