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Rh different depths; the value of different methods of manuring and applying fertilizers; and the comparative merits of different systems of culture. In connection with this work chemical analyses were made; experiments were carried on in self-and cross-fertilization; investigations were made in regard to the best treatment of certain insect enemies and plant-diseases; the climatic conditions were carefully noted; and the work begun in practical forest-tree culture was extended. The results of the investigations are intelligently and intelligibly described. We regard the document as a good specimen of what such a report should be.

arrangement of this book is somewhat different from that commonly adopted by teachers of organic chemistry. The lowest two members of the paraffin series are first considered, then, in order, their halogen, oxygen, sulphur, and nitrogen derivatives, and after these any peculiarities of higher paraffins and of their derivatives. Fifty pages are devoted to compounds which are at the same time alcohols and acids or aldehydes, etc. Next some account is given of the series of hydrocarbons homologous with the paraffins, and of their derivatives. The benzene series follows, and the various modifications and combinations of the ring molecule are described. Only the more important compounds in each group, and the more important reactions, receive attention. General directions are given for eighty-two experiments, a fair proportion of which the author advises each student to perform; for details in regard to analysis, etc., larger works are to be consulted. The author has taken pains to make the student see for himself the reasons for adopting the prevalent views in regard to the structure of the compounds of carbon, and has aimed to give a general view of the whole field, leaving minute descriptions to the chemical dictionaries. The book is a welcome addition to the unsatisfactory list of text-books in organic chemistry.

republication is made in answer to requests by geologists and others for the reports, which have been several years out of print, or very rare. "Of the value of the scientific discoveries, the generalizations, and the descriptions of the geological formations contained in these reports," says the editor, "there can be no better evidence than the frequency with which they are referred to and quoted by all who are engaged in exploring the geology of the Virginias, and the aid they have given to the development of the industrial resources of these States, which they foreshadowed, and in fact often clearly pointed out, at a time when the geology of the State was unexplored." The reports are arranged substantially in the order in which they were made, with the preliminary correspondence and the arguments addressed to the Legislature for the continuance of the appropriations, so that they have an historical as well as scientific value. The author himself desired to condense and codify the reports, and present them with his special map and sections, as a single whole, but time and opportunity never came for doing so. Thus, the editor's work has been simply to revise the reproduction of the original reports and maps. But a number of papers additional to the reports, relating to the geology of the Virginias, have 'been embodied in the volume.

this manual is laid out a short course of laboratory work, beginning with general chemistry, and including something of both qualitative and quantitative analysis. The book has been made especially for college students who have not studied chemistry, and have time only to gain some familiarity with chemical operations, without devoting much attention to chemical philosophy. The author has avoided the use of complicated or expensive apparatus, and has aimed to give clear and full explanatory details of