54 



NA TURE 



[November 20, 1902 



which is beyond their comprehension. Undoubtedly, 

 for a thorough training in electrical engineering the prac- 

 tical and theoretical sides of the subject must receive 

 equal attention, but not all students can attend institu- 

 tions where this is to be obtained. Many have of neces- 

 sity to be satisfied with some sort of compromise, and 

 one welcomes a book which is sound in its treatment and 

 is admirably calculated to give such students the know- 

 ledge and information they most require. 



Selection of some sort, when dealing with so large a 

 subject, is of course necessary ; the author has, we think, 

 made a wise choice in the branches with which he deals 

 and in the manner in which he treats them. These 

 include, in addition to the general principles underlying 

 the subject, batteries, accumulators, measuring instru- 

 ments and supply meters, arc and incandescent lamps, 

 and the continuous-current dynamo and motor. Par- 

 ticular apparatus is only described when it illustrates 

 the general principles. Perhaps in a few instances there 

 is a little too much detail, as, for example, in the 

 description of the recording mechanisms used in meters. 

 We would gladly see some of this matter omitted, and 

 such branches as telegraphy, telephony and electro- 

 chemistry treated on broad lines instead. Mr. Sewell 

 has the power of clear exposition, and has succeeded 

 well in avoiding too mathematical treatment ; the illus- 

 trations and diagrams are excellent. M. S. 



The Force of Mind : or, the Mental Factor in Medicine. 

 By A. T. Schofield, M.D., M.R.C.S., &c. Pp. xiv + 

 309. (London : J. and A. Churchill, 1902.) Price 5^. 

 net. 

 In t this book, which is written for medical practitioners, 

 Dr. Schofield appeals for a fuller recognition of the 

 influence of the " mind " in causing and in curing disease 

 of the body, and urges medical men to work for the 

 reclamation of those waste and unmapped regions in 

 which the religious fanatic and the quack doctor have 

 hitherto been allowed to reign, occasionally producing, 

 among much that is harmful, remarkable cures. He 

 would have the subject taught and studied in the 

 hospitals and great medical schools as a part of the 

 regular curriculum of every medical student. There 

 can be no doubt that the reforms advocated are much 

 needed and that Dr. Schofield performs a useful service 

 in thus pointing out the weak and neglected side of 

 modern medicine. The author supports his contentions 

 with many quotations from high authorities, both ancient 

 and modern, and by the citation of numerous cases, and 

 gives from his own experience many practical hints that 

 should be valuable to practitioners. From the point of 

 view of the psychologist, the book is vitiated throughout 

 by the insistence upon the part supposed to be played by 

 "the unconscious mind." This seems to be a figment 

 similar in function to von Hartmann's "unconscious,'' 

 i.e. it is a hypothetical agent to the activity of which is 

 assigned all that is obscure and difficult of explanation in 

 the workings of the nervous system. It is a radically 

 vicious hypothesis because it is one that tends to baffle 

 rather than to quicken the impulse to research. We are 

 told that the phrase is not used merely to cover the more 

 complex workings of the nervous system that are not 

 accompanied by consciousness, and no reasons are 

 assigned for rejecting this, which may now be called the 

 generally accepted and intelligible view of the matter. 

 The author seeks to support his position by quoting Dr. 

 Bastian's plea, " Let us make mind include all un- 

 conscious nerve actions," and in so doing reveals the 

 dire confusion of his own thoughts on this subject. He 

 good-naturedly pokes fun at those who objectify 

 "Nature" as a healing agent and then commits the 

 same error, replacing "Nature" by the vis medicatrix 

 naturae, which he identifies with the unconscious mind, 

 and thus commits himself to the somewhat absurd dogma 



NO. 1725, VOL. 67] 



that such remedial processes as compensatory hyper- 

 trophy of the heart and phagocytosis are manifestations 

 of the power of" the unconscious mind." Unless it can be 

 shown, as at present it cannot be, that nervous activities 

 and conscious processes together are inadequate to the 

 explanation of all the facts of our mental life, the assump- 

 tion of a third mysterious agent, call it " the unconscious 

 mind " or "subconsciousness" or what you will, is much 

 to be deprecated. W. McD. 



Introductory Chemistry for Intermediate Schools. By 

 Lionel M. Jones, B.Sc, A.R.C.Sc.(Lond.) Pp. vii + 

 195. (London : Macmillan and Co., Ltd.) Price 2^. 

 The standard of this book is suitable for the junior 

 classes of intermediate and secondary schools in which 

 chemistry is used as a form subject, and the matter in it 

 covers almost the same ground as that in the chemical 

 part of Perkin and Lean's " Introduction to Chemistry 

 and Physics." The treatment is rather different, as the 

 historical side is not mentioned. The students are ex- 

 pected to have been taken through some course in 

 physics or experimental science before they begin this 

 course. It is important that they should have done so, 

 as they are supposed to understand the balance, to weigh 

 to milligrammes and to know the meaning of many 

 physical terms. 



The book opens with chapters on the description of 

 bodies. Much attention should be given to this, as in a 

 recent examination, when a fragment of Iceland spar 

 was given for description, only a very small percentage 

 of candidates recognised that definite shape was charac- 

 teristic of the substance. Then follow chapters on simple 

 operations, solution, evaporation, distillation. Afterwards 

 come chapters on rusting, combustion, oxygen, hydrogen, 

 chalk, coal and coal-gas, salt and salt-gas, and finally on 

 acids and bases. 



Some of the methods appear to us to be too elaborate 

 for young children. There is, for instance, the compli- 

 cated aspirator, which experience has taught the present 

 writer is hardly ever clearly grasped. The correction 

 for pressure is always a difficult point. Again, the 

 students should never be allowed to make statements 

 such as " 1 litre of hydrogen weighs o"09 gm." or "den- 

 sity of chalk-gas 000198 gm. per c.c." without stating 

 definitely the temperature and pressure at which the 

 weight or density has been ascertained. 



We should have liked to have seen more attention 

 given to the indestructibility and conservation of matter. 

 This principle of chemistry cannot be grasped too early. 

 Many of the elementary experiments are conducted with 

 its tacit assumption, and we think it should be pointed 

 out to the student. S. S. 



Next to the Ground; Chronicles of a Country Side. By 

 Martha McCullock Williams. Pp. xii 4- 386. (London : 

 Heinemann, 1902.) 

 In this dainty little volume, the author affords English 

 readers a most interesting series of glimpses of the 

 charms and passing events of everyday country life in the 

 United States, after the fashion which so many writers 

 have made familiar in England. A close observer of 

 nature, and evidently imbued with the spirit that every- 

 thing has an interest of its own, if looked at in the 

 proper light, the author has hit upon a congenial subject, 

 and treated it in a manner which affords an excellent 

 example of the best style of "nature-teaching." The 

 scene is laid in a southern county lying to the westward 

 of the Alleghanies and eastward of the Mississippi, 

 nearly midway between the mountains and the river ; and 

 whether describing ploughing with mules or oxen, dis- 

 coursing of the quail, the partridge or the opossum, 

 discussing shooting and fox-hunting or writing on horses, 

 cows and pigs, the author is equally at home and 

 equally interesting. Some of the information given, such 



