Adams, of Johns Hopkins University (N. Murray, 25 cents), gives an account of the German practice, which is spreading among American universities, of making special collections of books for the use of students in special branches of study. It contains also a short paper advocating the extension of the system to public reference libraries, in connection with courses of lectures, and another describing the similar practice arising in England under the name of university extension.
Mr. Edward Potts's monograph on FreshWater Sponges (Philadelphia: Academy of Natural Sciences) has been prepared for the purpose of describing genera and species, mostly North American, that have been discovered since the publication of Mr. Coates's "Description and Classification" (London) in 1881; to give the results of the examination of the character and variations of already known North American species, and for use as a book of reference on all "good" species. The author further hopes to revive, among lovers of Nature, the appreciation of the existence of sponges in our fresh waters; and to show how to find, collect, classify, and preserve them.
Skeleton Notes upon Inorganic Chemistry, by P. de P. Ricketts and S. H. Russell (John Wiley & Sons, New York), is a book of blanks for preserving notes of lectures, experiments, or studies. The present volume is labeled Part I, and is devoted to the non-metallic elements. A definite number of pages is allotted to each element, the section being preceded by a table giving the ascertained constants and properties of the element, its applications, and its principal binary compounds.
Of the Course of Lectures on Electricity by George Forbes (Longmans, Green & Co., London and New York, $1.60), five were delivered in 1886 before the London Society of Arts, and the sixth—which shows the applications of the general principles to one department of practical engineering—was delivered at the Electrical Exhibition in Philadelphia in 1884. The lectures were intended to meet the desires of an intelligent audience, ignorant of electrical science, but anxious to obtain sufficient knowledge to enable them to follow the progress now being made in it; and the attempt is made to present in clear language the fundamental facts governing electrical phenomena in such a manner as will leave the reader nothing to unlearn.
In Loomis's Contributions to Meteorology Reviewed (K. Kittredge, Ann Arbor, Mich., 50 cents), H. Helm Clayton has compiled a summary of the series of papers which Prof. Loomis has published in the "American Journal of Science and Arts," and which are collectively pronounced "one of the best pieces of work in inductive meteorology of the present age." This summary, covering the chief results of the discussions, is intended for those persons who have not access to the papers in their complete form.
The Conferencias Filosóficas, or Philosophical Lectures; second series, Psychology, of Enrique José Varona (Havana), comprises a series of thirty lectures which were given in the Academy of Medical, Physical, and Natural Sciences of Havana in 1880 and 1881, and have been already printed in various numbers of the "Revista de Cuba." The opening lectures explain the general principles and foundations of the science, and the importance of the phenomena of movement to its study. They are followed by discussions of the various corporal senses in their order, and then by their relations and qualities of sensation and perception, memory, representation, association, imagination, the emotions and sentiments, the processes of determining and acting, suggestions respecting classification, and a bibliography.
Prof. Balfour Stewart and W. W. H. Gee have undertaken a series of small books on Practical Physics, of which vol. I. Electricity and Magnetism (Macmillan, 60 cents), has already been issued. This volume is based on the one devoted to the same subject in the "Elementary Lessons in Practical Physics" by the same authors. It is a laboratory manual, consisting largely of simple experiments and measurements in electrostatics, magnetism, and current electricity, the principles of which are at the same time explained to the student. In order to make the book complete in itself, a chapter is inserted describing the use of scales, calipers, wire gauges, the balance, etc. In the appendix will be found plans of certain school laboratories, a list of apparatus, tools, and materials, and other information that should be
