S6^ EXPEEIMENT STATION RECORD. 



sive diet of carbohydrates without protein did not lead to a gain in weight but 

 rather to a loss. 



Absorption and fate of tin in the body, W. Salant, J. B. Rieger, and E. L. 

 P. Treuthardt {Jour. Biol. Chem., 11 (WU), No. 2, pp. 265-273).— Soluble tin 

 salts subcutaneously injected were found in the contents of the gastro-intestinal 

 canal and in smaller quantities in the urine in tests with laboratory animals. 

 The skin contained from 20 to 25 per cent, and the liver on an average about 5 

 per cent of the total amount injected. 



"After feeding soluble salts of tin to rabbits for from 3 to 4 days, and to dogs 

 for from 2 to 4 weeljs, only traces could be detected in the urine. After feeding 

 soluble tin salts to rats for 4 months appreciable quantities were found in the 

 body. Soluble tin salts given intravenously disappeared from the circulation 

 within 2 to 3 hours. 



" The above data justify the conclusions that the gastro-intestinal tract is the 

 chief organ for the elimination of tin ; that the liidney plays a subordinate 

 though an important role. Elimination of the metal is very slow ; appreciable 

 quantities are eliminated during the first and second days. 



"Absorption of tin from the gastro-intestinal tract may take place under cer- 

 tain conditions." 



Do foodstuffs contain substances at present unknow^n ■which are impor- 

 tant for the maintenance of life? E. Abderhalden and A. E. Lampe (Ztschr. 

 Oesam. Expt. Med., 1 (1913), pp. 296-35J,; abs. in Chem. ZcnthL, 1913, II, No. 6, 

 pp. 522, 523; Jour. Chem. Soc. [London], IO4 {1913), No. 6U, I, p. U09).—A 

 critical study in which the authors contend that the existence of vitamins and 

 similar substances has not been definitely established. 



On the influence of atmospheric pressure, temperature, and humidity on 

 animal metabolism, W. Thomson {Mem. and Proc. Manchester Lit. and Phil. 

 Soc., 57 (1912-13), pt. 3, No. 13, pp. 8, pis. 2).— From the observation that the 

 percentages of carbon dioxid in the air exhaled from the lungs of a number 

 of people were on certain days nearly all low while on other days they were 

 nearly all relatively high, the author was led to conduct a series of experiments 

 in which the carbon dioxid in the air exhaled from the lungs was determined 

 and at the "same time observations made of the barometer, hygrometer, and 

 thermometer. 



It was shown by experiments that the percentage of carbon dioxid in the 

 exhaled air was greater when the inhaled air had been previously dried with 

 strong sulphuric acid, from which the author assumed that metabolism would 

 be greater when breathing dry air than when breathing damp air. It was 

 observed that the percentage of carbon dioxid in the exhaled air was greater 

 at high elevations than in valleys and also greater in valleys than in a deep 

 coal mine, from which the assumption is made that a low barometric pressure 

 would produce increased metabolism, while high barometric pressure would 

 result in decreased metabolism. 



Greater metabolism, as indicated by production of carbon dioxid, was ob- 

 served when the body was surrounded by cold air than when it was surrounded 

 by warm or hot air, but if the body remained in cold air and warm or hot air 

 was breathed metabolism was greatly increased. It was also noticed that the 

 breathing of pure dry oxygen produced no greater metabolism than that of 

 ordinary dry air. It was found that the metabolism was greatly increased 

 for some time after violent exercise had been taken. 



The data of these experiments with human beings and similar ones with 

 laboratory animals are presented in tabular form, from which it appears " that, 

 on all occasions where the barometer, hygrometer, or thermometer alters appre- 

 ciably, there is a corresponding change in the percentage of carbon dioxid in 



