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Rh exhibit, as a whole, by various American writers; many accounts of American education by foreign visitors; notes on the exhibits of separate States and foreign countries; and a series of papers prepared for the World's Library Congress, which together constitute a treatise on library economy. Among the subjects presented in other parts of the report are American Educational History; the Report of the Committee of Ten on Secondary School Studies, with papers relating thereto; Pecuniary Aid for Students; the Education of the Negro; and Medical Education. The usual statistics are presented. Those of the common schools show an increase of 1·2 per cent in enrollment and 3·45 per cent in average attendance over the preceding year.

Number 1 of Volume III of The Transit, a magazine published by the Engineering Society of the State University of Iowa, is entirely taken up by a monograph on Portland Cement, from the pen of Charles D. Jameson, Professor of Engineering at the university. A general consideration of the properties of lime and cement is followed by some historical data regarding the early use of cement both here and abroad, a general review of the methods of manufacture and testing, and the chemical processes concerned in the hardening of hydraulic cements. A number of good pictures show the various pieces of apparatus employed in its manufacture, and several structures in which the so-called monolithic, or artificial stone construction, has been used.

The last publication in the New Brunswick school series to reach us is a little Teachers' Manual of Nature Lessons, by John Brittain. It aims only, the author says, to be a useful index to some of the elementary chapters of the book of Nature, and to indicate briefly the means by which children may be led to read them with pleasure and profit. The text consists of suggestions for talks and simple experiments illustrating some of the more elementary facts of geology, chemistry, physics, and natural history. (J. & A. McMillan, St. John, N. B.)

A historical and descriptive sketch of The Yellowstone National Park, by H. M. Chittendon, has recently come to hand. It deals first and principally with the history of the upper Yellowstone, from the days of the early explorers to the present time. The descriptive portion of the work contains a fairly comprehensive treatment of the natural features of the park. Some good maps and a number of well-chosen pictures, the latter of which are somewhat marred by poor paper and printing, add value to the book. A few illustrated biographical sketches of the early explorers and a bibliography of the literature pertaining to the region are appended.

Much of the time expended in computations is wasted through the use of an excessive number of places of figures, and through failure to employ logarithm tables. The use of logarithms for work of four or more places, not only effects an important saving of time over direct multiplication or division, but also conduces to greater accuracy. Computation Rules and Logarithms, by S. W. Holman, consists of a number of simple rules indicating the number of places to be used in a given computation; "an explanation of the use of the notation by powers of ten; certain instructions, more or less novel in form, as to the use of the logarithm and other tables; and a collection of useful tables." The book is well bound and printed. (Macmillan, $1.)

The Molecular Theory of Matter, which has seldom been given more space outside of Germany than a chapter or two in a general work on physics, now has a volume, by A. D. Risteen, devoted to it (Ginn, $2). After giving some general considerations, the author divides his subject into the kinetic theory of gases, of liquids, and of solids, molecular magnitudes, and the constitution of molecules. He aims only to present the accepted views on these topics in a form that can be readily grasped by students, and where competent physicists disagree he lets the fact be known. There are frequent references to original sources, and some fifty diagrams and other figures are used.

The Eclectic School Readings is a series of books to supplement the usual school reading books. Two have come to us, Stories of Great Americans for Little Americans, designed for the usual second-reader grade, and Stories of American Life and Adventure, for the third-reader grade (American