FOODS — HUMAN NUTRITION". 369 



of polished rice, casein in varying amounts, millv fat, and a salt mixture was 

 supplemented by the following hoated preparations from milk : Milk from 

 which the casein had been removed (whey), heated in the autoclave; milk from 

 which the casein and albumin had been removed, boiled six hours ; and lactose 

 (heated in the autoclave). 



The following summary of conclusions it given : 



" Skim milk powder which has been wet and long he«ted in a double boiler 

 or heated for a period of one hour in an autoclave at 15 lbs. pressure, no 

 longer supports growth as does the unheated product. When heated, milk 

 powder also loses its property of supplementing certain rations made up of 

 polished rice, plus salts and milk fat : i. e., rations which require both protein 

 and water-soluble accessory to make them support growth. 



" Wheat embryo, which is as efQcient as milk powder in supplementing 

 such rice rations, can be heated for one hour in an autoclave at 15 lbs. pressure 

 without manifesting any deterioration in this respect as does milk. 



" Skim milk from which the casein has been removed (whey) can be heated 

 in an autoclave at 15 lbs. pressure for one hour without noticeable loss of its 

 nutritive properties. It still supplies the water-soluble accessary in active 

 form. 



" Whey from which the albumin has been removed by coagulation can be 

 kept at the boiling temperature for six hours without any appreciable loss 

 in its activity as far as the water-soluble accessory Is concerned. Also lactose 

 which has been heated in an autoclave for one hour at 15 lbs. pressure still 

 behaves as does the unheated product in supplying to rations the water-soluble 

 accessory. 



" Heating casein in a moist condition for one hour in an autoclave at 15 lbs, 

 pressure destroys its biological value as a complete protein. Heated casein or 

 heated milk powder are shown to have little, if any, toxicity. The deteriora- 

 tion is due to a loss of value of the protein fraction of the ration through 

 changes wrought in the casein." 



The estimation of carbon dioxid tension in alveolar air, P. Roth (Jour. 

 Atner. Med. Assoc, 65 {1915), No. 5, 413-418, figs. 5). — A method is described 

 for obtaining samples of alveolar air. In the author's opinion, the carbon 

 dioxid tension in alveolar air is a most valuable index of the intensity of 

 acidosis in the body. 



A text-book of military hyg'iene and sanitation, F. R. Keefer {Phila- 

 delphia and London: W. B. Saunders Co., 1914, PP- 305+8, figs. 47). — Though 

 designed particularly for the u.se of those interested in problems of military 

 hygiene, this book has much of interest to the student of home economics 

 problems, as is shown by such chapter headings, as physical training, prevent- 

 able diseases, clothing, water supply, foods and their preparation, and the dis- 

 posal of wastes. The volume is based in considerable measure upon actual 

 experience gained through a long period in promoting the physical condition, 

 health, and fitness of soldiers, and deals primarily with measures which insure 

 these resiUts. 



An improved respiration calorimeter for use in experiments with man, 

 C. F. Langworthy and R. D. Milner {U. S. Dept. Agr., Jour. Agr. Research, 

 5 {1915), No. 8, pp. 299-348, pis. 7). — This paper describes the respiration 

 calorimeter used for experiments with man in the Office of Home Economics, 

 U. S. Department of Agriculture. Detailed descriptions are given of the con- 

 struction of the respiration chamber, the methods and apparatus employed in 

 the determination of the respiratory exchange, and the measurement of latent 

 and sensible heat. An apparatus for measuring muscular work performed by 



