Prof. _Silas W. Holman_ attempts the presentation, in _Matter, Energy, Force, and Work_,[AD] of some of the fundamental ideas and definitions of physics in a plain and logical manner. His purpose is not to set forth the experimental side of the subject or to describe phenomena or laws. He rather assumes a slight knowledge of these, and proceeds to develop the concept and definitions. The author regards a clearer thinking on these subjects as of special importance to engineers and members of the other technical professions, because correct views upon them have become essential in those professions through the progress of the applications of science to the industrial arts. These applications are likewise of considerable interest to the untechnical members of the community. Professor Holman has composed his book with the principle of presenting the subject of physics in logical sequence, and has divided it into two parts, the first of which contains the matter immediately proper to the subject, with discussions of substance or matter, motion; energy and its forms; force; kinetic energy, force-measurements, work, potential energy, and matter again, as distinguished from substance. The second part comprises summaries of the chief theories of the nature of matter, force, and energy, including the kinetic theory of gases, Le Sage's theory of gravitation, the vortex-atom theory, and a discussion of the nature of energy and matter, with observations on chemical energy and the ether. [Footnote AD: Matter, Energy, Force, and Work. A Plain Presentation of Fundamental Physical Concepts, and of the Vortex-Atom and other Theories. By Silas W. Holman. New York: The Macmillan Company. Pp. 257. Price, $2.50.] The _Short Course in Music_, prepared for use in schools where a complete course is not thought necessary, by _F. H. Ripley_ and _Thomas Tappen_, is embraced in two books, of which we notice the second (American Book Company). Familiar songs are made the basis of instruction, some of those which appear as melodies in Book One being repeated here in full score. All other material has been prepared especially for this book. The music and directions are adapted equally for unchanged and changed voices. Voice training and the elements of phrasing and expression are furnished in a group of _solfeggios_ at the close of the book. Theory is given in condensed form, but one that, it is claimed, embraces all the essential elements of vocal music.