Sbptembek 19, 1913] 



SCIENCE 



407 



tions of applied science, is, I am sure, very 

 largely due to the success of Sigma Xi. 



Sigma Xi stands " for intellectual energy 

 rather than sordid ambition," and the volume 

 so ably compiled by Professor Ward richly 

 demonstrates the fact that it " has become a 

 prominent factor in most of our universities." 

 In the words of one of its founders in conse- 

 quence of its influence: 



Men have come to know that knowledge of the 

 present is far more important than tradition — 

 that individual discernment, power of initiative, 

 and honesty, surpass all authority in the equip- 

 ment of a scholar of the new sort. 



Marcus Benjamin 



An Introduction to the Chemistry of Plamt 



Products. By Paul Haas and T. G. Hill. 



Published by Longmans, Green and Co., 



London, New York, Bombay and Calcutta. 



1913. Pp. xii + 401. 



The progress of chemistry, perhaps more 

 than of any other science, may be divided into 

 great epochs, in each of which one branch of 

 the science is found to be far more productive 

 of permanent results than are the other di- 

 visions. 



The centuries-long period of alchemy grad- 

 ually merged into the period when chemical 

 researches were conducted with the view of 

 enlarging the number of compounds which 

 could be utilized in medicine. 



Following the discovery of the nature of 

 combustion, we begin to find the first organized 

 chemical research, devoted in the main to in- 

 organic chemistry, which rewarded us with a 

 gradually increasing number of elements, with 

 the atomic hypothesis, and the gas laws. 



Thus until 1828 nearly all of the chemical 

 investigations were confined to inorganic 

 chemistry, for the compounds of carbon were 

 supposed to be formed only by the action of 

 life. When, however, Wohler made his fa- 

 mous synthesis of urea, a new field was opened 

 and the immense number of organic com- 

 pounds listed in " Beilstein " are in a large 

 measure the result of the studies of the period 

 of organic chemistry. 



For a time organic chemistry overshadowed 



inorganic chemistry until, under the leader- 

 ship of men like Arrhenius, Ostwald, Nemst 

 and Van't Hoff, a new chemistry was created 

 which we know as physical chemistry. And 

 even in our own time we have seen the science 

 of radioactivity follow the discovery of radium 

 by Mme. Curie. 



During all of these advances the chemistry 

 of the life processes has been more or less neg- 

 lected. To be sure, a great many of our uni- 

 versities list courses in " physiological chem- 

 istry," but until very recently these have been 

 devoted almost entirely to the study of nutri- 

 tion and the chemistry of pathology, and even 

 to-day the study of the chemistry of the life 

 processes is only at a beginning. This is per- 

 haps necessary, for it would be a useless task 

 to undertake to determine and measure the 

 life processes without the exact knowledge 

 furnished by the organic and physical chem- 

 ists. 



We are thus, probably, near the beginning 

 of a period of biological chemistry, not only 

 the chemistry of animal life, but the chemis- 

 try of plant processes as well, not only from 

 the standpoint of the physician and utili- 

 tarian, but from the broader standpoint of the 

 study of life itself, its chemical products and 

 the laws by which it is governed. 



We have many admirable text-books deal- 

 ing with physiological chemistry, but text- 

 books which are suitable for a course in plant 

 chemistry are rare. This may perhaps in part 

 explain the absence of such courses from the 

 curricula of our universities. It is, there- 

 fore, a pleasure to find such a book as " An 

 Introduction to the Chemistry of Plant Prod- 

 ucts." 



Modeled somewhat after Iloppe-Seiler's 

 " Handbuch der physiologisch- und patholog- 

 isch-chemischen Analyse," but dealing only 

 with plant products, there is a wealth of in- 

 formation in the 400 pages. Each group of 

 plant constituents is discussed, first under the 

 general group, then under the group subdi- 

 visions, and lastly each compound is given, its 

 structural formula (when known), its proper- 

 ties, its chemical reactions, its niiero-chemical 

 reactions in many cases, the qualitative tests 



