FOODS HUMAN NUTRITION. 565 



Da tit are given regarding the effects of the exeriiou on men of different ages 

 and itrevions training, from whieh the anthor concludes that even very severe 

 and unusual body exertion combined with great demands on the heat regulating 

 machinery of the body does not as a rule produce any deleterious results. On 

 the contraiy. it induces good sleep and a feeling of refreshment even in persons 

 little used to walking. The men in good training and general condition un- 

 doubtedly had the advantage during the ascent, but the final results were favor- 

 able also for those to whom the ascent was difficult or even painful. 



The study seems to prove that to include considerable muscular exertion in 

 a winter vacation trip raises the general tone of the body by strengthening the 

 heart and improving the vasomotor activity. 



A method for the study of the periods of rest and activity of laboratory ani- 

 mals, J. S. SzYMANSKi {P/lii(J(-r\s Arch. Plii/siol., J58 U'JJJ,), No. 6-8, pp. SJ,S- 

 38^, figs. 35). — A detailed description is given of a delicate modification of the 

 kymograph which the author employed in the study of a number of small labo- 

 ratory animals (such as goldfish, canary birds, etc.) during day and night. A 

 diagrammatic explanation of the modification is given. 



On the respiratory exchang-e in fresh water fish. — I, On brown trout, J. A. 

 Gardner and Constance Leetham (Biochcm. Jdur., 8 {1914). Xo. 4, pp. 374- 

 390, figs. 2). — Detailed descriptions are given of apparatus and experimental 

 technique. The data reported may be summarized as follows: 



Oxygen absorption was approximately proportional to the body weight at a 

 given temi)erature and yielded a respiratory quotient of about 0.8. The con- 

 siderablj' lower respiratory quotient noted at low temperatures is explained 

 by the authors on the theory that at low temperatures the animals are in a 

 state of hibernation or starvation and live on their fat, partially converting it 

 into glycogen and sugar. 



Laboratory experiments with, air, F. S. I^ee (Jour. Amcr. Med. Assoc, 63 

 (1914), ^0. 19, pp. 1625-1628). — In this summary of the contributions of his 

 laboratory to the knowledge of air in relation to ventilation problems the 

 experiments being carried out by the New York State Commission on Ventila- 

 tion are very briefly described. 



In these experiments one group of laboratory animals (cats) was kept 

 for a i>eriod of 6 hours at a temperature of 21° C. (70° F.) and in an atmos- 

 phere of 54 i)er cent humidit.v. Another group of animals was kept under con- 

 ditions of humidity as high as 89 i>er cent at temiwratures as high as 33°. 

 Under these conditions, which were comparable with those of a hot and humid 

 summer day. the body temperature rose on an average of 0.5° during the 6-hour 

 period. At the end of this time stimulation of certain muscles of the animals 

 showed that they were able to perform only an amount of work which was 14, 

 18, and 20 per cent less than was the case with animals of the first group which 

 had been kept under more favorable atmospheric conditions. A diminution of 

 13 iier cent in the blood sugar was also noted. Further experiments are being 

 carried on along this line. 



[Report of the work of the] nutrition laboratory, F. G. Benedict (Carnegie 

 Inst. Washington Year Book, 12 (1913), pp. 241-254). — Notes of changes and 

 improvements of equipment, brief general descriptions of the various metabolism 

 experiments in progress, and brief reviews of the publications issued during 

 the year 1913 are given. 



International catalogue of scientific literature. Q — Physiology. QR — 

 Serum physiology (Inteniat. Cat. Sci. Lit, 10 (1914), pp. yiII+1155, V+182 + 

 S6).— This volume, like the preceding ones (E. S. R., 20, p. 1168), contains 

 references to scientific articles on subjects regarding general physiology, includ- 

 ing among other subjects those of respiration, heat production, digestion, 

 absorption, and metabolism. 



