The preparation of his _Elementary Text-Book of Botany_[I] was undertaken by Mr. _Vines_ to meet a demand which appeared to exist for a less bulky and expensive volume than his Students' Text-Book. A more important feature than the diminution of the bulk is claimed in the simplification which the contents have undergone from the omission of certain difficult and still debatable topics. The usual divisions into morphology, anatomy, physiology, and systematic botany are followed; but the caution is appended that it must not be forgotten that these are all parts of one subject, different methods of studying one object--the plant. Hence they must be pursued together. "For instance, the morphology of the leaf can not be profitably studied without a knowledge of its structure and functions; and it is also important to know what is the systematic position of each of the various plants whose leaves afford the material for study. In a word, the student should not attempt to read the book straight through from the beginning as if it were a novel. On the contrary, he may begin with any one of the four parts as his main subject; but that part must be studied in close relation with the other three parts"; and this method of proceeding is facilitated by the insertion of a large number of cross-references in the text. A satisfactory account is given by _C. Francis Jenkins_ in _Animated Pictures_[J] of the development and present state of chronophotography, or the art of "conveying by persistence of vision a counterfeit impression of objects in motion through the display in rapid succession of a series of related pictures." The story shows very clearly that this, like most other inventions of consequence, is no sudden discovery, but is the culmination of a very long series of experiments. The principle of it is embodied in the toy, the zoetrope, the origin of which is not known, though a citation from Lucretius indicates that something of the kind existed in his time. With the discovery of instantaneous photography, a new application of the principle of the zoetrope was found. Muybridge and Marey were pioneers in this development with their photographs of the motions of animals valuable in sciences. Since their work was begun the photographic processes and apparatus have been greatly improved. Mr. Jenkins forecasts a brilliant and useful future for the art, which he hopes will be prosecuted along the line of other than its present most popular uses. The book is practical as well as historical and prophetic, and contains an account of Mr. Jenkins's phantoscope as the first successful "moving picture projecting apparatus," for which he received the Elliott Cresson medal from the Franklin Institute.