the liveliest interest. A good sanitary education involves a very considerable understanding of the method of Nature.
We heartily welcome, therefore, the increasing hygienic literature of the age, and are glad to see that the best minds are devoting themselves to it, and giving the public the results in various forms of their serious and careful studies. The little volume now before us is a timely and most valuable contribution to the subject in its practical, every-day aspects for the use of house-holders. First of all, it is a careful and trustworthy book by a thoroughly prepared man, who has had large experience of hygienic subjects as Sanitary Inspector of the New York City Health Department. It has been Dr. Tracy's business to apply sanitary science to the art of living under our present domestic constructions and arrangements. He has had to meet actual difficulties that arise from the influence of bad air, bad sewerage, bad drainage, bad house-construction, bad precautions respecting infectious diseases, bad food, bad water, and bad plumbing. It seemed to him that there was needed a little book simply of facts and results, free from theory, discussion, or speculation, and written in the plainest style, that would serve for every-day guidance in relation to all these sanitary subjects. It is full of brief rules and directions, and useful information regarding sanitary contrivances, how they are to be obtained and what they cost, and from this point of view it may be regarded as a practical summing up of the most urgent requirements, the best facilities, and the clearest directions, that will be of service every day and to everybody. We have read the book with care, and can recommend it, without hesitation or qualification, as one that should be kept for constant reference in every house.
INTERNATIONAL SCIENTIFIC SERIES.
The Concepts and Theories of Modern Physics. Second edition, revised; with an Introductory Essay. By J. B. Stallo. New York: D. Appleton & Co. Pp. 358. Price, $1.75.
The first edition, and a pretty large one, of this profound work was exhausted some time ago, which speaks well for the interest of American readers in the thorough discussion of the fundamental ideas that are at the basis of science and philosophy. The continued demand for the work making necessary a second edition, the author has subjected the text to a close revision, and prefixed to it a masterly introduction of forty-four pages. He here avails himself of the criticisms passed upon the work, both in this country and abroad (where several editions of it have also appeared), to restate the purpose of the volume, which has been a good deal misunderstood, and to reply to such objections as seemed to require attention. The effect of this lucid and brilliant discussion will be to greatly facilitate the general apprehension, and to enhance the interest of the work to those who take it up for the first time.
In our review of Judge Stallo's book upon its first appearance, we pointed out that it is a philosophical study of the relations of metaphysics to physics, designed to show that many of the leading physicists of the age are by no means as far emancipated from old metaphysical influences as it is customary to believe. He attacks some of the fundamental ideas of modern physics as being strictly metaphysical assumptions, and shows historically how they have survived, and performed their old duties in new relations. But the book was construed as an onslaught upon the foundations of modern physics in the interests of a bad metaphysics, and the author was called upon to offer his substitutes for the fundamental doctrines he aimed to sweep away. We quote some passages from the new introduction, which leave no room for further misunderstanding:
