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274 revising the determinations of the atomic weights of all the elements. He does not claim that any of the results he has reached are final, but admits that each one of them is liable to repeated corrections. The real value of the work, he believes, lies in another direction; the data have been brought together and reduced to a common standard, and the probable error has been determined for each series of figures. Thus the ground is cleared, in a measure, for future experimenters.

are glad to see such a book by such an author from such a place. A lady engaged in teaching practical chemistry in an institute of technology, and applying her science to the art of improving domestic life, affords an example of the fitness of things which is seen much too rarely. To the eye of a stupid public opinion, cooking and cleaning are very vulgar things—the operations of menials and scullions. But to the eye of science they are most interesting processes, tasking thought to master them, giving pleasure in understanding them, and valuable benefit in applying them. To the eye of ignorance, however cultivated, there is nothing about cooking and cleaning that is worthy of respect, and they are therefore left to the incompetent, who give us bad work; but, if they were better understood, practice would be improved, and we should have more wholesome cookery and more perfect cleanliness.

Mrs. Richards's neat little brochure is a contribution to domestic education which, though too slight, will be well appreciated. It is not an attempt to compress a great deal of information in a small compass, but to make the subject clear as far as it is treated. Her "Chemistry of Cooking" is at the same time a course of brief lessons in chemistry; that is, enough of the science is thoroughly explained to make its applications intelligible. We cordially commend it as an excellent beginning in a direction that must in future be more carefully and thoroughly pursued.

work of the year covered by this report consisted chiefly of the arrangement for the museum of the crystalline rocks gathered during the previous seasons in the northern part of the State, including the cupriferous series; determinations in paleontology; examinations of building-stones; the study of the hydrology and water powers; field work in the southwestern part of the State; and the examination of the "Lake region" of the center, with reference to hydrology and the distribution of forest trees.

authors have taken advantage of the revelations which the recent International Electrical Exposition at Paris afforded of the extent to which electrical force has been developed as a working power, and the variety of purposes to which it has been practically applied, to prepare this elegant work, showing what has been done in that direction, when, and how. The large mass of material which they had to dispose of has been divided among six books, in the first of which is reviewed the history of artificial illumination, and the different phases through which it has passed from the dimly tempered darkness of the ancients, with their rude oil-lamps, through the stages of tallow, sperm, and stearine candles, and the improved lamps of modern days, to the beginnings of the electric light. The second book treats of voltaic or arc lights, the manner in which the arc is produced, the fabrication of the carbons, and the mechanism of the regulating apparatus, and furnishes descriptions of the different lights of this class. The third book is devoted to incandescent lamps, and includes descriptions of the Edison, Swann, Lane Fox, and Maxim lamps. In the fourth book the different kinds of apparatus for generating the electric current, and in the fifth book the several systems for securing its distribution and division, are described;