Page:Popular Science Monthly Volume 51.djvu/869

Rh with a distinctive heading. A table of the more important European formations is appended to the volume, but few of the subdivisions having been mentioned in the text. Another appendix contains the system of classification of the animals and plants which has been used in the book. There is a full index, and the mechanical execution of the volume is of a high order.

Prof. Storer's work on the chemistry of agriculture, which first appeared in 1887 and was revised in 1892, has been again revised. It is based on the lectures which the author has delivered at the Bussey Institution, a department of Harvard University, now for twenty-five years. The chemical nature and behavior toward plants of every substance that has been used to any extent as a fertilizer are set forth in these volumes. Other subjects discussed are the relations of water to the soil, the effects of tillage, rotation of crops, the management of hay and grain crops, the production of ensilage, etc. The additions that have been made in this edition, and the fact that it has been entirely reset in larger type, have necessitated printing the work in three volumes instead of two as heretofore.

The second volume of Britton and Brown's Illustrated Flora of the Northern United States, etc., gives the families, genera, and species from Portulaca to the dogwoods and tupelos, seventy-two families, in Choripetalœ; and from the clethras to Buckbean, sixteen families, in Gamopetalœ. We have already indicated, in our notice of the first volume of this work, its general character and scope. We have to refer specially here chiefly to the pains which are taken to make the work as a whole and the particular descriptions plain to the most untechnical reader. Every species is figured as to general habits, leaf, flower, and fruit; English names are given or the botanical names are translated into meaning English for each family, genus, and species; and English measures are used, so that the plain student may conceive at once and as if with his eyes shut the dimension indicated without having to look at a scale or make a mathematical reduction. Complete indexes are provided of English and of Latin names.

Mr. Thayer's essay on the Hebrews in Egypt and their Exodus is an attempt to find if there be not in the Pentateuch a reasonably credible, historic narrative which may be accepted with as much confidence as any other chapter of history so ancient. The argument is, in brief, that, owing to the strong race feeling of the Jews, the genealogies of their families were the most carefully recorded and the most uniformly coherent, consistent, and jealously preserved part of their history; that here we shall find firm ground to stand on, if anywhere; that the annals of the Pharaohs as now accepted by Egyptologists support and confirm these genealogies; and through these is to be traced the real thread of historic truth. While the author does not hold to the usually accepted views concerning the Pentateuch, he has no sympathy with what is called the destructive school of criticism. His argument is, on the contrary, intended to be constructive and preservative.

"A practical treatise for practical men" is what Dr. Louis Bell has aimed to make his recent book on Electric Power Transmission (Johnston Co., $2.50). After some discussion of elementary electrical principles and transmission of power by other than electrical means, he gives a chapter to power transmission by continuous currents, which up to the present time is the commoner mode. He then takes up the coming mode of power transmission, namely, by alternating currents. He points out the properties of alternating circuits that have a direct bearing on power transmission, and discusses monophase, polyphase, and heterophase systems and the forms of apparatus used with each. A