Page:Popular Science Monthly Volume 50.djvu/579

Rh, coma, wounds, and burns are discussed in detail. Nervous diseases and insanity receive considerable attention. Bathing, massage, the administration of medicine and food, children's diseases, signs of death, and care of the dead bring us to the last four chapters, which treat of pregnancy, childbirth, and gynæcological nursing in general. The work is intended as a text book, for use in a school or hospital, and should be supplemented by clinical study.

In the preparation of his Story of the Earth, Dr. Heilprin has sought to present briefly, forcibly, and in a more popular form than in most books of a similar nature, the general facts of geology. Avoiding the recapitulation of numberless details with which authors are easily tempted to burden a work n this science, and making his account narrative rather than adopting an analytical method, he has endeavored to make the book comprehensive enough to meet the needs of the average student, and enlist the attention of readers who would pass by a difficult technical work and would yet not be satisfied with an ordinary elementary one. He has made it a model of compactness, simplicity, lucidity, and readableness, touching upon all essential points, and dwelling on them long enough to make them understood, yet without tiring the reader. The illustrations are numerous, all photographs from the things themselves, largely American, and represent clearly what it is intended to show. First, the rocks are described as a whole; then "what a mountain teaches" is told; the operative forces in geology are presented—snow and glaciers, underground waters, the forces in the earth's interior, volcanoes and earthquakes, and corals and their island products; three chapters are given to the description of fossils; the physiognomy of the land surface is delineated; and the more useful metals and minerals, building stones, soils and fertilizers, and some of the commoner rock-forming minerals and minerals occurring in rocks are described.

The great interest which Prof. Weismann's theories regarding the problems of heredity have excited has led to the translation of a work by Dr. Oscar Hertwig, The Biological Problem of To day, which was published last year in Germany. The book is practically a criticism of Weismannism, Dr. Weismann being the most prominent upholder of what is called the Præformation theory. The main question at issue is a purely biological and very technical one—namely, the process by which organic development is carried on. The Præformationists believe that the future organism exists in the germ, with its various parts differentiated, but of course so extremely minute as to render any physical appreciation of this fact quite impossible. The upholders of what is called Epigenesis, on the other hand, insist that in the beginning there is no such differentiation, but that the original germinating mass is practically homogeneous, and the subsequent specialization is "impressed" on different portions of similar material. Dr. Hertwig's book consists of a statement of his reasons for believing in epigenesis. Most of them are based on data gained during investigations of cell structure and growth, and by means of experiments on the lower forms of organized matter. Dr. Hertwig's name is associated with many of the most important advances in our knowledge of cells and embryology, and his views on the question in dispute are of the utmost value. In his introduction the translator has given a brief general statement of the early stages in the development of the vertebrate, which is intended as a help for readers not familiar with the subject of embryology.

We have just received a third edition of Dr. Brinton's Myths of the New World. The first edition, which appeared so long ago as 1868, has been somewhat superseded by later publications, and, while many of the recent contributions to the subject are not considered by Dr. Brinton to be as satisfactory as the work of the earlier writers, many of the opinions put forward in the original work as theories have now been accepted by most students of mythology, and require a restatement in more emphatic form. In its original edition the work was intended more for the thoughtful general