October 30, 1914] 



SCIENCE 



641 



suspected as little a relationship between the 

 two acids. It required years of labor to bring 

 the two independent lines of inquiry to a 

 common ground and to a mutual understand- 

 ing. 



The inquiry into the chemical structure of 

 uric acid led up to the classical work of 

 Fischer on the " purin " derivatives. This 

 work established the relationship of uric acid 

 to xanthin, hypoxantliin, guanin and adenin — 

 basic substances discovered in the extracts of 

 animal tissues. It then became evident that 

 the uric acid of the urine is a product of ani- 

 mal combustion of purin bases. 



On the other hand, the inquiry into the 

 structure of nucleic acids led up to the knowl- 

 edge that these acids contain in their mol- 

 ecule purin bases. Thus, by some display of 

 imagination, the origin of the purin bases of 

 tissue extracts could be explained by a rupture 

 of the complex structure of the nucleic acid 

 molecule. The genesis and the fate of uric 

 acid became obvious. This triumph of knowl- 

 edge is unquestionably important for its own 

 sake. However, in this place it may be of 

 service as an illustration of the scope of 

 biological chemistry as compared with that of 

 the structural organic chemistry. 



The discovery of the arrangement of atoms 

 in a given molecule is the aim of the struc- 

 tural chemist. The physical and chemical 

 properties of a molecule are determined by 

 the arrangement of the component atoms. 

 The work of the chemist is completed when he 

 is successful in arranging hypothetically all 

 the atoms of the molecule in such a manner 

 that the conduct of the molecule appears a 

 natural sequence of this arrangement. 



Not so simple is the task of a biological 

 chemist. A tissue component is not only a 

 chemical, but also a biological unit. It is not 

 only a reacting body but also a structural ele- 

 ment of cells and tissues. Furthermore, it 

 reacts not only in its state of integrity, but 

 also in its state of dissociation. The dissocia- 

 tion is most generally a complex process, and 

 is controlled by well regulated mechanisms. 

 In a word, the scope of biological chemistry is 

 not only the chemical structure of substance, 



but the life cycle of the structure, and the 

 relation of this cycle to that of the other tissue 

 elements. 



Hence, the biochemical problems are very 

 complex, and for the present it is difficult to 

 point out any tissue component regarding 

 which our knowledge is complete. 



The subject of nucleic acid is one of the 

 most successful chapters in the history of 

 biochemical inquiry. Not that information 

 is complete either in regard to the structure or 

 in regard to the conduct of this group of 

 substances. But the information that is lack- 

 ing is small as compared with that already ac- 

 quired. And the information acquired con- 

 cerns equally the biologist, the chemist and 

 the physician. 



To sum up all the recent progress in this 

 field of research is a very difficult undertaking. 

 Professor W. Jones in his monograph on 

 " Nucleic Acids " has acquitted himself of the 

 task in a most masterly manner. The work 

 contains a very systematic and keen analysis 

 of all the numerous publications in this field 

 of biochemical research. And yet, the book 

 reflects the personality of the author and his 

 interests as an investigator. Dr. Jones has 

 contributed considerably to the knowledge of 

 the chemical structure of nucleic acids, but 

 his most important contributions relate to 

 the process of their disintegration in the 

 organism. Naturally the chapters on the 

 " conduct " of the nucleic acids carry most 

 inspiration. Hence, the biologist, the physi- 

 cian, and the physiologist will read the book 

 with special interest. However, also the chem- 

 ist will find a complete and very comprehen- 

 sive review of all the work dealing with the 

 chemical structure of nucleic acids. 



The first part of the monograph deals with 

 nucleins, nucleoproteins, and with " nucleic 

 acids " in general. The second chapter of this 

 part gives a good account of the chemistry of 

 nucleic acids of animal origin, and the con- 

 cluding chapter reviews the results of the re- 

 cent work on the nucleic acids of plant origin. 



The second part gives a critical resume of 

 the very extensive literature dealing with the 

 questions of biological formation of nucleic 



