Page:Popular Science Monthly Volume 43.djvu/143

Rh output of coal in 1891 reached the enormous total of one hundred and eighty-five millions of tons—giving employment to about six hundred thousand persons. The book contains some excellent illustrations, and will be read with interest by those who desire to study the social and labor questions. (London: Whittaker & Ck). New York agents, Macmillan & Co. 1892.)

Few persons outside those connected with engineering business are aware of the importance of the pattern-maker. In a volume of 180 pages A Foreman Pattern-maker has embodied the most useful hints to apprentices and students in technical schools under the title The Principles of Pattern-making. The book is fully illustrated with one hundred and one engravings, and includes a useful glossary of the common terms employed both in pattern-making and molding. Considering the size of the volume it is really surprising to find such a fund of useful information upon the fundamental principles of pattern-making condensed into so small a space. The illustrations were nearly all made by the author himself, and are almost self-explanatory. It is published by Whittaker & Co., London. (Xew York agents, Macmillan & Co. Price, 90 cents.)

The Microscopical Examination of Potable Water is a little volume of 160 pages which contains a good deal of useful information concerning the best methods and apparatus necessary for the microscopical and bacteriological examination of water. The author, George W. Rafter, devotes considerable space to an explanation of the advantages of filtration by sand over the Parkins cloth method, and gives minute details of several examinations and analyses of the various public water supplies of the country, basing the arguments which follow upon the results of an examination of the Boston Sudbury River Water Supply. The remarks upon the effect of light upon the formation of starch in the algæ are interesting, and he claims that in certain lights the starch remains protoplasmic, and that a low temperature and darkness are unfavorable to the growth of algæ in the water supplies. The book is No. 103 of the Van Nostrand Science Series.

In a volume of 322 pages entitled Figure Skating, Simple and Combined, Messrs. Montagu S. Monier-Williams, Winter R. Pidgeon, and Arthur Dryden, the most eminent of British figure skaters, have given an elaborate treatise upon the development of figure skating in England. It is profusely illustrated with cuts and diagrams, and is published by Macmillan & Co., New York ($2.26).

Leonard Dobbin, Ph. D., and James Walker, Ph. D., D. Sc, have issued a useful handbook of 240 pages entitled Chemical Theory for Beginners. It is written with the object of assisting beginners in obtaining an elementary knowledge of the principles upon which modern chemistry is based. The chapters on Elements and Compounds, Chemical Action, Vapor Density, and The Kinetic Molecular Theory are interesting from a standpoint far advanced from the beginner. The use of symbols has been disregarded in this work, so that a very young student in chemistry will have no difficulty in understanding the most intricate examples of chemical compounds, etc., which are given. The kinetic theory of gases, as discovered by Clerk Maxwell and Clausius, is very simply demonstrated. The book is published by Macmillan & Co., of London and New York (70 cents).

In a volume of 978 pages the Interstate Commerce Commission has issued its Third Annual Report on the Statistics of Railways in the United States. It is a comprehensive tabulation of the classification, mileage, earnings, expenditures, and capital of the various railway systems of the country. In the reading matter which prefaces the voluminous and interesting statistics there is a complaint that the statistical data procurable from the monthly reports of the different railway corporations is of little value to publicists and economists; and it is claimed that the present system of bookkeeping in vogue among the accountants of the different roads "leads inevitably to an erroneous balance-sheet." The remarks upon and the statistics of the enormous increase of mileage will be read with interest by economists, and the fact that this increase is proportionately far greater in the Southern States will be a surprise to those who have not carefully observed the industrial progress of that section of the country.

D. C. Heath & Co., Boston, have issued a new publication entitled The Complete