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Rh of Clark University, has endeavored to present the mathematics of the subject in a form more assimilable by the student than has been available heretofore (Macmillan, $3.50). Since graduates of American colleges are, as a rule, insufficiently prepared for taking up mathematical physics, the author has prefixed a mathematical introduction and a treatment of the Newtonian potential function to this work. For a similar reason he has included a treatment of the fundamental principles of mechanics. These matters occupy nearly half of the volume. Little or no reference has been made to experimental methods in electricity, these being left to other works. The general purpose of the treatise is to present the results of the electrical theory as it stands to-day, after the labors of Faraday, Maxwell, Helmholtz, Hertz, and Heaviside.

The Bulletin of the Department of Labor for May, 1897 (No. 10), contains a statistical report of one hundred and twelve pages on the Condition of the Negro in Various Cities. The investigation which furnished the data for this report was originally undertaken to ascertain the causes of the excessive mortality of negroes in Chattanooga, Savannah, and Boston. Afterward it was extended to seventeen Southern cities and the city of Cambridge, Mass., and besides statistics of sickness and mortality it has been made to embrace facts concerning sizes of families, number of rooms occupied, rents paid, sanitary condition of houses, occupations, earnings, and the number of defective, maimed, and deformed persons. The statistics do not cover the whole of the cities in which the investigation was made. A representative group of houses was taken in each, as the persons who gave their time to the work could not do more. This bulletin contains also a comparison of figures as to the work of men, women, and children for periods ten years apart, and miscellaneous minor articles.

Volume XXVIII, Part I, of the Harvard Observatory Annals is a catalogue of Spectra of Bright Stars discussed by Antonia C. Maury. The spectra of six hundred and eighty-one of the brightest stars north of declination -30°, of which about forty eight hundred photographs were obtained, are comprised in this catalogue. As the investigations were made several years ago, they could not take account of the recent discoveries respecting the spectrum of helium, but a discussion of the relation of the spectra of stars of the Orion type to that of helium is contained in supplementary notes. Volume XXXVI of the Annals completes the series of five volumes devoted to Observations of Stars by Prof. William A. Rogers. A list of errata for the whole series of volumes is included.

In the Fifteenth Annual Report of the Bureau of Ethnology the director, after describing the work of the year, proceeds to outline conclusions that have been reached by the bureau in regard to regimentation, the satisfaction of justice, and related matters in savage society. The chief of the accompanying papers is by William H. Holmes, on Stone Implements of the Potomac-Chesapeake Tidewater. Extensive deposits of rudely flaked stones are found in and about the city of Washington, and careful study of them has shown that they are on the sites of workshops connected with extensive quarries. From examinations of large quantities of rejectage it has been determined that the product of the flaking operations was a leaf-shaped blade. It was further ascertained that such leaf-shaped blades are to be found on Indian village sites in all parts of the surrounding country. Studies of quarries of other materials in the neighboring high land gave similar results, and in order to round out the subject all known classes of implements have been studied. These studies have not revealed the slightest evidence as to the occupancy of the region by any earlier people than the known Indian tribes. Jesse Walter Fewkes contributes a memoir on The Group of Tusayan Ceremonials called Katcinas, which is copiously illustrated with cuts and colored plates showing the masks and other paraphernalia used in these rites. There is a special report on The Repair of Casa Grande Ruin, by Cosmos Mindeleff, and other papers are The Siouan Indians, by W J McGee, and Siouan Sociology, by James O. Dorsey.

The work on Stones for Building and Decoration, by George P. Merrill, originally published in 1891, now appears in a revised and enlarged edition. Reading matter and