360 



SCIENCE. 



LVol. VII , No. 16? 



compass he has given an exhaustive description of 

 the masses of gray matter and intricate network 

 of white fibres of which the brain consists ; and 

 he has done this from the stand-point of a com- 

 parative anatomist, which greatly enhances the 

 values of his statements. There is such rapid 

 progress being made in the department of nervous 

 diseases, that it is perhaps not surprising that a 

 few of the positions held by the author will need 

 to be modified in the second volume : in fact, he 

 admits this in his preface. But the great mass of 

 the facts stated in the text are fixed and definite, 

 and must be familiar to all future investigators 

 in this field. 



To the general reader the physiological portion 

 of the volume will be much more attractive than 

 its anatomical details. Here, again, Meynert is 

 worthy of attention. It is pretty generally ad- 

 mitted that the method of introspection so long 

 advocated by psychologists is incapable of giving 

 satisfactory results in the investigation of those 

 processes in which mind and matter meet : hence 

 of late years new methods have been sought. 

 One of these is to study the mental processes as 

 they develop in the infant, and to watch the man- 

 ner in which ideas are acquired and voluntary 

 powers become available. This method has been 

 employed by Preyer and Kussmaul in Germany, 

 and by Dr. Mary Putnam Jacobi in this country. 

 Meynert has made use of it to some extent in dis- 

 cussing the manner in which knowledge is ac- 

 quired and stored up, and in which the various 

 memories gained through the senses are associated. 

 For example : if a pin touches the eye of an in- 

 fant, the lid closes. This is a reflex act carried 

 out by a simple mechanism independent of any 

 act of consciousness ; but, coincident with the 

 reflex act, a number of impulses are sent to the 

 brain, along fibres which, on reaching the cortex, 

 give rise to the conscious perception of the ap- 

 pearance of the pin, of the pain of the prick, and 

 of the motion which has been performed. Each 

 of these perceptions occurs in a different part of 

 the brain, since each sensory organ is joined to an 

 area of its own. But the three perceptions occur 

 simultaneously ; and, as all parts of the cortex 

 are joined with one another by fibres passing from 

 one ana to the next, the three perceptions are as- 

 sociated both in percept ion and in memory: hence, 

 when the pin is seen again, the memory of the 

 pain arises, and the memory of the motion which 

 stopped the pais ; and thus the mere sight of the 

 pin leads the child to close the eye. The percep- 

 tion of the reflex motion has given the infant the 

 knowledge of the possession of a muscle capable 

 of movement ; and the motion, having once be- 

 come conscious, can be reproduced voluntarily by 



an effort which excites to action those cells which 

 retain the memory of the motion (pp. 156-161). 



A second method of psychological investigation 

 is that of experimental physiology. This is open 

 to the objection that many acts of animals are 

 misinterpreted by physiologists, who look at many 

 of the acts as manifestations of voluntary mental 

 action instead of being instinctive. The differ- 

 ences of those who advocate or oppose the local- 

 ization of functions as deduced from experiments 

 are to be traced rather to their varying interpreta- 

 tions of the result of the experiments than to 

 those results themselves. Meynert is a believer in 

 the localization of functions, as is every physician 

 who has seen much of brain-diseases, and he 

 presents clearly the arguments in its favor derived 

 from the investigations of Fritsch and Hitzig and 

 Munk. A third means of studying the relations 

 of mmd and matter is the consideration of in- 

 dividuals who present disturbances of mind 

 associated with definite forms of destruction of 

 brain-tissue. Meynert's opportunities for such 

 study are very great, as he has at his disposal the 

 immense number of patients collected in the 

 Vienna hospital. That he has made good use of 

 his material is evident in the sections of this work 

 which treat of the functions and nutrition of the 

 brain. In the next volume this part of the work 

 will be fully expanded. By means of these three 

 methods much that is new and entertaining has 

 been found in the physiology of thought, and 

 much that is important both to the alienist and 

 to the psychologist is brought forward. The 

 book, therefore, appeals to a rather wider circle 

 of readers than its title would indicate. 



Those who have read the original will sympa- 

 thize with the translator in the difficulties of his 

 work. It is a misfortune of the author that he is 

 at points exceedingly abstruse and even obscure ; 

 and this fact, as well as the very technical stjle 

 of the original, has rendered the task undertaken 

 a serious one. It has been done in a painstaking 

 manner, the original being followed as closely as 

 possible, without, at the same time, taking from 

 the English its own construction and idiom. The 

 translation has been made with the consent of the 

 author and by one of his pupils. It is evident 

 that he has labored hard, although in some places 

 the meaning is difficult to grasp. This difficulty 

 is to be traced to the original, as can be deter- 

 mined by a comparison of (he two, and hence 

 must not be laid at the door of the translator. 

 The manner in which the publishers have pre- 

 sented the volumes is to be commended, no ex- 

 pense having been spared in reproducing the 

 many valuable diagrams and illustrations of the 

 original. M. A. S. 



