624 



NA TURE 



[October 27, 1904 



The isolation and determination of the probable con- 

 stitution of tryptophane by Hopkins and Cole, and that 

 of oxyphenylaethylamine by Langstein and Emerson, 

 may also be mentioned as some of the most important 

 additions to our knowledge of the products of the 

 hydrolysis of the proteids by the action of trypsin. Dr. 

 Cohnheim appears to have omitted to mention the dis- 

 covery of the latter substance. 



Our knowledge of the chemistry of the diamino- 

 acids and other basic products of hydrolysis has not 

 been so markedly increased. The constitution of 

 histidin has not yet been determined, although the 

 evidence so far obtained points to it being a pyrimidine 

 derivative. The discovery by Herzog that it gives the 

 biuret reaction is of much importance in view of the 

 fact that this test has been used to distinguish between 

 the more complex products of proteolysis which still 

 retain proteid characters and the simpler chemical 

 bodies resulting from more complete decomposition. 



The tables compiled by Dr. Cohnheim which give 

 the nature and quantity of the products of hydrolysis 

 of various proteids and albuminoids form a very useful 

 addition to the book. 



The third chapter of the general part of the work 

 gives an interesting account of the chief views held 

 with regard to the constitution of the proteids. The 

 most interesting advance in this field is due to 

 E. Fischer, who has shown that the amino-acids 

 possess in a marked degree the power of reacting with 

 one another to form more complex bodies. The proto- 

 type of these substances — glycylglycin — results from 

 the union of two molecules of glycin with the elimin- 

 ation of the elements of water, the amine group of 

 the one molecule reacting with the carboxylic group 

 of the other to form an amide. By extending this 

 synthesis Fischer has succeeded in preparing com- 

 pounds of three or more molecules of various amino- 

 acids to form compounds which he terms polypeptides. 

 Some of the more complex polypeptides resemble pep- 

 tones in many of their chemical properties. 



In the special part of the work the section on the 

 proteids of plants has been much extended. The 

 section on nucleoproteids gives a good account of 

 recent work elucidating the constitution of the pyr- 

 imidine derivatives, uracil, thymin, and cytosin. Con- 

 siderable additions, embodying the work of Nencki and 

 Zaleski, and of Kiister on the decomposition of 

 haematin, have also been made to the chapter on the 

 blood pigments. 



The second edition of the work well maintains the 

 high standard for completeness and accuracy secured 

 by the first one. 



OVR BOOK SHELF. 



Sleinents of General Radio-Therapy for Practitioner!:. 



By Dr. Leopold Freund, Vienna. Translated by 



Dr. G. H. Lancashire. Pp. xix + 538; illustrated. 



(New York and London : Rebninn, Ltd., 1904.) 



Price 21s. net. 

 Dr. Freund is so well known to English workers in 

 electrotherapeutics that any work written by him will 

 be welcome. To his earliest writings the profession 

 is largely indebted for the first experimental work in 



NO. 1826, VOL. 70] 



radio-therapy, and the results were sufficient to indicate 

 the possibilities of X-rays in therapeutic work as well 

 as in diagnosis. The work before us shows that Dr. 

 Freund has based his experimental research upon a 

 thoroughly scientific knowledge of what has been done 

 by others as well as by himself, and consequently all 

 workers with X-rays will feel indebted to him for his 

 book and gratefully acknowledge this. 



In his preface Dr. Freund states that he has 

 attempted to bring the essential features of a recent 

 form of treatment before the notice of a larger circle 

 of medical men, that he has tried in a comprehensive 

 way to explain the technique, the indications for treat- 

 ment and the results to be expected, while at the same 

 time tabulating and arranging the fundamental 

 physical laws so as to explain the physiological effects. 

 That he has succeeded no one will doubt who reads the 

 work, and that the views of others have not been for- 

 gotten is made evident by the fact that he quotes more 

 than eight hundred writers upon the subject. The 

 author admits that this branch of science can hardly 

 be said to be more than in its infancy, that there are 

 gaps in our knowledge to be filled in and errors to be 

 corrected ; but notwithstanding the doubt expressed in 

 some quarters we have already achieved brilliant 

 theoretical and practical results which lead him to hope 

 that radio-therapy will obtain an acknowledged place 

 among our methods of treatment. In support of this 

 view he says one need only refer to the undeniable and 

 astonishing results already achieved in skin disease. 



.^fter a short but expressive introduction referring 

 to the phvsical aspect of the question, Dr. Freund 

 divides the work into five sections. The first deals with 

 the elements of electricity, and this section should be 

 useful to medical practitioners who are desirous of 

 obtaining the acquaintance with physics necessary to 

 understand this special branch of surgery. The second 

 part treats fully of high-frequency currents, the third 

 section is devoted to X-rays, the fourth to Becquerel 

 rays, and the fifth to treatment with heat and light 

 rays. 



A careful perusal of the different chapters will con- 

 vince anyone that Dr. Freund has fullv succeeded in 

 his aims; and that the text-book under notice will 

 become a popular one is certain. That it will be re- 

 garded as one of the standard works on the subject no 

 one can doubt. 



English workers are largely indebted to Dr. 

 Lancashire for his excellent translation of the work, 

 and to Mr. Clarence A. Wright for his notes on 

 instrumentation published in connection with the 

 English edition, which are introduced at the end of 

 the book. 



The whole is clearly and scientificallv written. 

 There are one hundred and seven illustrations taken 

 from the original text, and the author, translator, and 

 publisher are to be congratulated upon the success of 

 their efforts. 



Physiography. An hitrociiiction to the Study of 

 Nature. By T. H. Huxley. Revised and partly re- 

 written by Prof. R. A. Gregory. Pp. xi + 423; with 

 301 illustrations. (London : Macmillan and Co., 

 Ltd., 1904.) Price 4.S. 6d. 

 The task of revising and bringing up to date Huxley's 

 inspiring text-book of physiography was one not to be 

 lightly undertaken, but it could not well have been 

 placed in better hands than those of Prof. Gregory. 

 In spite of the many fine qualities of the original 

 volume, and of the author's belief that its methods 

 could be adapted with little difficulty to any locality 

 by an intelligent teacher, it can scarcely be questioned 

 that the usefulness of the book was somewhat restricted 

 by its special reference to the Thames and its basin. 



