REVIEWS. 393 



Introduction to General Chemistry. By Gustavus Detlef 

 Heinrichs, M.D,, LL.D., etc. 8vo, pp. 400. (St. Louis, Mo., U.S.A. : C. 

 G. Heinrichs. London : H. Grevel and Co. 1897.) 



The author tells us that a radical change in the methods of teaching 

 Chemistry is greatly needed, and in the volume before us he attempts the refor- 

 mation. He presents the entire science in a strictly graded course ; the princi- 

 pal points being determined in the order of their historic growth. The 

 discovery of oxygen is not presented until its necessity can be understood ; the 

 atomic theory comes last. There are a number of plates, showing Crystals, 

 Diagrams, Apparatus, etc., besides many illustrations iu the text. 



A New English Dictionary on Historical Principles. Edited 

 by Dr. James A. H. Murray. (Oxford : The Clarendon Press. London : 

 Henry Frowde.) Price 5/- 



This part contains the words from Doom to Dziggetai, and completes the 

 third volume. The entire portion of the Dictionary occupied by the letter D 

 contains a total of 19,051 words, made up of 13,478 main words; 2,099 sub- 

 ordinate ; 1,480 special combinations ; and 1,944 obvious combinations. 



The three volumes now completed of this exhaustive work — (A — E)— con- 

 tain no fewer than 97,608 words ; that is to say, nearly 100,000 words, simple 

 and compound, have thus far been dealt with. Of these, more than 72 per cent, 

 are current and native or fully naturalised, whilst 24 per cent, are obsolete. 



Of the volume just completed, 740 pages are occupied by the letter D and 

 488 by E. 



Euclid : Books I.— IV. By Rupert Deakin, M.A. Cr. 8vo, 

 pp. viii. — 309. (London : W. B. Clive. ) Price 2/6. 



This is one of the '* University Tutorial Series," in which the aim of the 

 author, who has had more than 20 years' experience in teaching EucHd to large 

 and small classes — has been to make the intelligent study of Euclid as easy as 

 possible. 



The Tutorial Trigonometry. By William Briggs, M.A., 

 F.C.S., F.R.A.S., and G. H. Bryan, Sc.D., F.R.S. Cr. 8vo, pp. viii.— 326. 

 (London: W. B. Clive.) Price 3/6. 



The subject-matter of this book is treated under the different headings. 

 The first ten chapters deal mainly with what has been designated at Cambridge 

 " Trigonometry of One Angle" ; the next four chapters treat of Trigonometry 

 of two or more angles ; and the remainder of the book is devoted to Logarithms 

 and Trigonometry of Triangles. Answers to Examples are given at the end of 

 the book. 



European Butterflies and Moths. By W. F. Kirby, 

 F.L.S., F.E.S., etc. (London : Cassell and Co.) 



Since our last notice, we have received Nos. 36 to 45 of this important 

 work. Each part contains a beautifully coloured plate, showing larvie, pupae, 

 and perfect insects with their food-plants. These parts are published at 6d. each. 



Roentgen Rays and Phenomena of the Anode and Cathode : 

 Principles, Applications, and Theories. By Edward P. Thompson, M.E., E.E., 

 etc. Concluding chapter by Prof. W. A. Anthony. Roy. 8vo, pp. xviii.— 190. 

 (New York : D. van Nostraud Co. London : E. and F. N. Spon. 1896.) 



This book is divided into sixteen chapters, each paragraph being numbered, 

 and the table of contents gives the subject of each paragraph. The book 

 involves the disclosure of the facts and principles relating to the phenomena 

 occurring between and around charged electrodes, separated by different gaseous 

 media at various pressures. The specific aim is the treatment of the radiant 



