114 



SCIENCE 



[Vol. LVI, No. 1439 



means of silver salts have shown that approxi- 

 mately one third of the solids present unite with 

 the silver salts to form insoluble silver com- 

 pounds. About one half of the total vitamin, as 

 determined by feeding experiments on pigeons, is 

 present in these insoluble silver precipitates and 

 the other half remains in the filtrate. This un- 

 expectedly large unpreeipitable fraction of the 

 vitamin raises the suspicion that the portion ac- 

 companying the silver precipitates may not be in 

 chemical combination but simply held by adsorp- 

 tion. Further studies of the silver precipitates 

 and filtrates are in progress. 



Cow's milJc versus goat's milk as a source 0/ 

 the anti-soorbutic vitamin: C. H. Hunt and A. E. 

 Winter. Four weeks before the experiment start- 

 ed two cows and three goats were placed on the 

 same ration, consisting of equal parts of a grain 

 mixture and alfalfa haj-. Forty-four guinea pigs 

 were divided into eleven lots of four each and 

 were given a weighed daily amount of a basal 

 ration consisting of rolled oats 69 parts, auto- 

 elaved alfalfa flour 25 parts, casein 5 parts and 

 NaCl 1 part. All of the pigs received, with the 

 exception of the control lot, in addition to the 

 basal diet, a measured amount of milk eacli lay; 

 one half of the lots receiving cow's milk ar J the 

 other half goat's milk. The amount of milic fed 

 varied from 10-50 cc in increments of 10 cc. 

 The control lot died of scurvy in 26-30 days. The 

 pigs receiving 10 cc. of cow's milk survived from 

 42-53 days, while the survival period of those re- 

 ceiving 10 cc goat's milk was from 60-103 days. 

 Up to a period of 90 days one death from scurvy 

 occurred among the lot receiving 20 cc. cow 's milk, 

 while no deaths from scurvj' occurred among the 

 pigs receiving 20 cc. goat's milk. There was a 

 decline in weight of both lots receiving 20 cc. 

 milk, but the decline was greater with those re- 

 ceiving cow 's milk than with those receiving goat 's 

 milk. When the amount of milk fed daily was 

 increased to 30 cc. or more no difference was 

 noted between cow 's and goat 's milk as a source 

 of the antiscorbutic vitamin (C). 



Results oitained by feeding breeding gilts a 

 ration low m vitamin : J. S. Hughes and H. B. 

 Winchester. Breeding gilts receiving a feed 

 low in vitamin A and C developed no abnormali- 

 ties during the first ten months. At this time 

 they developed the eye trouble common to rats, 

 rabbits, dogs and other experimental animals, and 

 in addition to this they developed a nervous dis- 

 order manifested by a general incoordination ac- 

 companied by frequent convulsions. Two of the 

 eight did not breed, two died during the latter 



part of the gestation period, two aborted a few 

 days before they died, one farrowed dead pigs 

 and the last one went fourteen days longer than 

 the normal gestation period. Gilts, receiving 5 

 per cent, alfalfa as a source of their vitamin A 

 showed no abnormalities. Five per cent, alfalfa 

 did not furnish sufficient vitamin for normal 

 reproduction, as 28 per cent, of the pigs farrowed 

 by these sows were dead. 



Influence of the vitamin content of a feed on 

 immunity to roup: J. S. Hughes, L. D. Bush- 

 NELL and L. F. Payne. Chickens receiving a feed 

 low in vitamin w-ere much more susceptible to 

 roup than those receiving a similar feed high in 

 vitamins. Four pens, of twelve chickens each, re- 

 ceived feeds varying in their vitamin content. One 

 chicken from the pen receiving a feed high in 

 vitamins, eight from the pen receiving a feed low 

 in the fat-soluble vitamin, seven from the pen 

 receiving a feed low in the water-soluble vitamin 

 and nine from the pen receiving a feed low in 

 both fat and water-soluble vitamin, died with 

 clinical symptoms of roup or a disease similar to 

 roup. AU chickens were exposed to the roup 

 infection by keeping infected chickens in the pens. 



The detection and estimation of inorganic ac- 

 tivators in commercial rennin and pepsin prepara- 

 tions: Harper F. Zollee. An activator-free 

 pepsin or rennin solution coagulates dialyzed milk 

 with great difficulty at the optimum temperature 

 (41° C.) for rennin action. The presence of cal- 

 cium or magnesium ions accelerates the enzyme 

 action and gives the coagulum its normal physical 

 consistency. The differential between the rate of 

 coagulation in dialyzed milk and in undialyzed 

 milk furnishes a factor, which when compared 

 with a similar factor obtained from activator-free 

 enzyme solution under the same set of conditions, 

 furnishes a means of roughly estimating the 

 quantity of activator or accelerator present. 



A laboratory disinfectant solution to displace 

 mercuric chloride: Harper F. Zollee. Sodium 

 hypoehloride solution furnishes a means of pro- 

 viding an efficient, economical and safe sterilizing 

 agent for use in biological laboratories. In the 

 preparation of the solution it is essential to main- 

 tain a sufficiently high hydroxyl ion concentra- 

 tion for maximum stability — about Pjj 10.5. 

 Solution containing about 0.15 per cent, available 

 chlorine (0.32 per cent, sodium hypochlorite) will 

 destroy the most persistent of micro-organisms 

 within ten minutes. 



The decomposition of food by bacillus botu- 

 linus: I. K. Phelps and J. E. Basch. 



The feeding of non-lceto genie odd-carbon fats 



