464 



SCIENCE. 



[N. S. Vol. XXII. No. 563. 



and of the influence that the distribution 

 of rainfall and temperature in various 

 parts of the country has on the character 

 of the crop. 



Then the cross-breeder 's work begins : ac- 

 climatization alone is hardly likely to yield 

 the ideal plant, but by it are found plants 

 possessing the features, one here and one 

 there, that are desiderated; and starting 

 with this ground material the hybridizer 

 can eventually turn out an individual pos- 

 sessing to a large measure all the qualities 

 that are sought for. 



There is little hope that science can do 

 anything wholly new for agriculture; ac- 

 climatization, breeding and selection have 

 been the mainstay of farming progress 

 since the beginning of time, just as the 

 action of the nitrifying bacteria and of 

 nitrogen fixation by the leguminous plants 

 was instinctively apprehended by the ear- 

 liest farmers of whom we have any record. 



But with increasing knowledge comes 

 more power, and particularly the possibility 

 of accelerating the rate of progress; agri- 

 cultural improvements in the past have 

 resulted from the gradual and unorganized 

 accretions of the observation and experi- 

 ence of many men, often of many genera- 

 tions, now that we are provided by science 

 with guiding hypotheses and by the organ- 

 ization of experiment with the means of 

 replacing casual opinions by exact knowl- 

 edge. Even the properties of the soil and 

 the character of our farm crops and ani- 

 mals — stubborn facts as they are and deeply 

 grounded in the nature of thingsi — ought 

 to become increasingly plastic in our hands. 



A. D. Hall. 



SCIENTIFIC BOOKS. 



Physiological Economy in Nutrition. By 



EussELL H. Chittenden, Ph.D., LL.D., 



Sc.D. New York, F. A. Stokes Co. 1904. 



This notable volume, the production of 



Professor Chittenden and his coworkers, of 



whom Professor Lafayette B. Mendel is the 



most prominent, finally dispels the tradition 

 that a continued liberal allowance of proteid 

 in a normal diet is a prerequisite for the 

 maintenance of bodily vigor. 



Professor Chittenden had suffered from per- 

 sistent rheumatism of the knee joint and de- 

 termined on a course of dieting which should 

 largely reduce the proteid and calorific in- 

 take. The rheumatism disappeared and minor 

 troubles such as ' sick-headaches ' and bilious 

 attacks no longer recurred periodically as 

 before. 



There was a greater appreciation of such food 

 as was eaten: a keener appetite, and more acute 

 taste seemed to be developed and a more thor- 

 ough liking for simple foods. 



During the first eight months of the dieting 

 there was a loss of body weight equal to eight 

 kilograms. Thereafter for nine months the 

 body weight remained stationary. 



Two months of the time were spent at an 

 inland fishing resort, and during a part of this 

 time a guide was dispensed with and the boat 

 rowed by the writer frequently six to ten miles 

 in a forenoon, sometimes against head winds 

 (without breakfast) and with much greater free- 

 dom from fatigue and muscular soreness than in 

 previous years on a fuller dietary. 



During this latter period of nine months the 

 nitrogen of the urine was determined daily. 

 The average was 5.69 grams. During the last 

 two months this was reduced to 5.40 grams. 

 Experiments showed that about one gram of 

 nitrogen was eliminated in the fseces, and that 

 nitrogen equilibrium could be maintained with 

 dietaries of low calorific value (1,613 and 

 1,549 calories) containing 6.40 and 5.86 grams 

 of nitrogen. These figures correspond to diets 

 containing 40 and 36.6 grams of proteid in- 

 stead of 118 grams commended by Voit and 

 honored by habit and tradition. The foods 

 with the strongest fiavors are meats. 



Professor Chittenden believes that the large 

 quantity of proteid in the ordinary diet is due 

 to self-indulgence. He protests against such 

 indulgence and believes that a futile strain 

 is thereby placed upon the liver, kidneys and 

 other organs concerned in the transformation 

 and elimination of the end products of proteid 

 metabolism. 



