502 



NATURE 



[July 17, 19 13 



features of the book is the series of diagrams, 

 which are well drawn, and often a whole page is 

 devoted to a single figure, with the result that a 

 very clear representation is secured. 



(3) One is inclined to think that too much is 

 being done nowadays in the matter of adapting 

 branches of study to the special needs of various 

 classes of students. Text-books of physics, and 

 presumably of other subjects also, are written 

 from the point of view of subsequent work, and 

 the result is often detrimental to the students 

 themselves. It is scarcely possible to avoid a 

 certain looseness of language and an inexactness 

 of expression when the subject is submitted to the 

 special mode of treatment in question. The pre- 

 sent book is quite a good one in many ways, and J 

 no doubt contains a great deal of useful informa- 

 tion with regard to heat and heat engines. It is 

 good to find the subject introduced from the point 

 of view of energy, although the discussion of the 

 meaning of energy is evidently handicapped by 

 the knowledge on the part of the author of the 

 very limited training in mechanics possessed by 

 the students for whom the book is written. To 

 each chapter the author appends a summary in 

 heavy type of the important conclusions therein, 

 together with a number of problems based on the 

 work. Apart from the limitations imposed by the 

 mode of treatment referred to, this book is a 

 straightforward and lucid presentation of the 

 subject. 



(4) This pamphlet is frankly published for 

 "cramming" purposes. It is intended as a 

 synopsis for students reading for the Mechanical 

 Sciences Tripos, and especially for the "A" paper 

 in Heat. In order to make this perfectly plain 

 the author leads off with some forty lines of 

 doggerel, which, if committed to memory, 

 apparently ensures success in the examination. 

 To those students who regard their study of 

 physics from this point of view, the book will 

 prove useful in proportion to what they remember 

 of its contents ; to the serious student it can 

 scarcely be recommended. For so small a volume 

 the table ot "errata" is too long; indeed, it 

 rather looks as though this handbook has been 

 hurriedly prepared. 



(5) There is room for doubt as to whether 

 it is desirable in a book on electricity and 

 magnetism to avoid almost entirely references to 

 the physical, as distinct from the mathematical, 

 side of the subject. This is the only fault we have 

 to find with this treatise, which is otherwise quite 

 excellent. And even this objection disappears if 

 it can be guaranteed that the book will be read 

 concurrently with attendance at experimental lec- 

 tures and laboratory work. Most teachers find 



NO. 228l, VOI . Ql] 



that students of physics experience much more 

 difficulty with the mathematics it involves than 

 with the experimental principles upon which it is 

 based. To those students this book should prove 

 a boon. Here they will find presented in logical 

 order and in a simple manner an extensive series 

 of deductions from, and applications of, the funda- 

 mental laws of electrostatics, magnetism, and 

 electromagnetics. Numerous numerical examples 

 are appended to the various chapters, and at the 

 end of the book the more important formula; de- 

 veloped in ft are compiled in a list. The use of 

 this list, of course, involves the adoption of a par- 

 ticular notation in the memory of the student, and 

 this, perhaps, is a little inexpedient at a time like 

 the present, when notation varies so much ; but it 

 is not easy to see how to overcome the difficulty. 



(6) To those interested, both theoretically and 

 practically, in the transmission of electrical power 

 this volume should prove of great interest and 

 use. The author has carried out a large number 

 of calculations of the various electrical data re- 

 quired in this connection, with numerical examples. 

 Graphical methods are frequently resorted to, and 

 the treatment of the whole subject appears to be 

 very complete. 



(7) The chief objection to this type of book is 

 that it is very liable to become very dirty in 

 the hands of a slovenly boy, and very unsightly, 

 owing to numerous corrections, when written up 

 by a boy who, though clean, is not brilliant. The 

 instructions for the experiments are given clearly 

 and neatly, and it seems rather a pity to spoil 

 their appearance. The course comprises three 

 parts, arranged more or less in order of difficulty, 

 and a considerable number of simple experiments 

 in mechanics, heat, and the physical and chemical 

 properties of water and air are dealt with. At 

 the end of each lesson a number of questions, 

 intended for homework, are set. Presumably the 

 answers to these are to be recorded in a separate 

 notebook. Why not the experimental results 

 also? 



OUR BOOKSHELF. 

 Vegetation of the Peak District. By Dr. C. E. 

 Moss. Pp. x + 235 + plates. (Cambridge Uni- 

 versity Press, 1913.) Price 125. net. 

 Quickly following on Elgee's " Eastern Moor- 

 lands of Yorkshire," we have Moss's book on the 

 vegetation of the Peak district, especially in its 

 relations to geology and the chemical nature of 

 the soil. Faunistic relations, so ably discussed by 

 Elgee, are not considered by Moss. As the author 

 remarks, the Peak district has no definite geo- 

 graphical boundaries, but his maps of the plant 

 formations include th»' area lying between Mossley 

 and Penistone to the north, and, approximately. 



