888 EXPERIMENT STATION RECORD. 



egg albumen digested with pepsin and panereatin in which the effect of a number 

 of preservatives was studied, including salicylic, benzoic, and boric acids and 

 salts; sulphurous acid; saccharin; sugar; vinegar; ethyl and methyl alcohol; 

 salt ; formaldehyde ; smoke ; condensed smoke ; creosote ; and phosphoric, hydro- 

 chloric, and nitric acids, the following conclusions were drawn : 



" In an acid medium, the only preservatives or condiments used in these tests 

 which retarded peptic or pancreatic digestion, when in proportion of 1 :400 or 

 less, were salicylic acid, formaldehyde, smoke, condensed smoke, and creosote. 

 Of these, salicylic acid does not retard the digestion when present in proportion 

 of 1 :1000. 



"(a) In a neutral medium acid, preservatives and acid condiments increase 

 the factor of digestibility, due to a change of the neutral medium to an acid one, 

 and digestion proceeds normally as in the acid medium; (b) alkaline preserva- 

 tives change the character of the medium and the results are abnormal, the 

 action of the ferment being retarded. 



" In an alkaline medium, preservatives and condiments react abnormally, 

 depending on the degree of alkalinity, the action of the ferments being retarded." 



Similar tests were made with a number of mineral, animal, vegetable, and 

 synthetic colors. According to the results reported of the colors used " only 

 ultramarine, burnt sienna, chrome yellow and ponceau 2R. affect artificial 

 digestion with pepsin when used in quantities of 1 part of the color or less to 

 400 parts of the food. The results also indicate that the synthetic colors are 

 less active than animal and mineral colors and not more active than vegetable 

 colors. Vegetable and synthetic colors are directly digested by pepsin and by 

 panereatin, and when the amount of color exceeds 1 part to 200 a correction is 

 necessary, increasing the factor of digestibility 10 to 40 points. 



On Folin's theory of proteid metabolism, D. N. Paton (Jour. Physiol., 

 33 (1905) , No. 1, pp. 1-11, fif/s. 3) . — From experimental and other data presented, 

 the author concludes that the theory of proteid cleavage advanced by Folin 

 (E. S. R., 17, p. 167) regarding protein metabolism should not be based too 

 exclusively on the distribution of nitrogen in the urine of the subjects examined, 

 but that the possibility of urea being an end product of both exogenous and 

 endogenous metabolism should be considered. 



Strength, and diet. A practical treatise with special regard to the life 

 of nations, R. Russell (New York and Bombay: Longmans, Green d- Co., 1905, 

 pp. 6Jf9). — A vegetarian treatise. 



Cooking by cold: Some studies, E. Cutter (I)ietet. and Hyy. Gaz., 22 (1906), 

 No. 2, p. 79). — Tests are reported from which the author concludes that freezing 

 potatoes, onions, cranberries, and squashes changed some starch into dextrose. 



The effects of high external temperatures on the body temperature, respira- 

 tion, and circulation in man, A. E. P>oycott and J. S. IIaldane (Jour. Physiol., 

 33 (1905), No. 1, Proc. Physiol. Soc, 1905, p. XII).— In experiments with man 

 the body temperature in still air was found to rise above normal when the wet- 

 bulb thermometer rose above 31° C, while it remained normal whatever the 

 external temperature might be, provided the wet-bulb thermometer did not 

 rise above 31°. 



" The more the wet-bulb thermometer rose above 31° the more rapidly did 

 the body temperature rise. In moving air the wet bulb thermometer could be 

 allowed to rise to about 35° or a little higher without the body temperature 

 rising above normal. With rise of body temperature a marked fall in the 

 alveolar C0 2 pressure was observed. With rise of body temperature there was 

 a very marked increase in the pulse rate, along with a slight or tolerably marked 

 rise in the blood pressure." 



