432 Miss J. White. The Ferments and [Mar. 3, 



Low Temperatures. — The exposure of the grains to low temperatures, both 

 in the dry and moist conditions, had different effects from their exposure to 

 high temperatures. The mode of carrying out these investigations was as 

 follows : Seeds of fresh wheat, barley, oats, rye, and maize were dried in the 

 same manner as when testing for the effects produced by abnormally high 

 temperatures, and placed in perfectly dry glass tubes, which were carefully 

 sealed off, but which previously to sealing had been weighted with shot. 



Samples of the same kinds of seeds were put together with shot into 

 loosely woven muslin bags, and the tubes and bags were lowered into a flask 

 of liquid air. The weighting of the tubes and bags was necessary owing to 

 the specific gravity of the liquid air being about equal to that of water. 



The liquid air remained in the flask for about three days and all the seeds 

 were completely immersed in it for fully two days. 



The seeds were removed from the liquid air and some of each kind were 

 set for germination, while corresponding seeds from the same packets which 

 had not been subjected to the temperature of the liquid air were also set to 

 serve as controls. Also some of the seeds from the tubes and muslin bags 

 were ground up and their ferments precipitated as before. Neither the 

 germinating power nor the enzyme reactions appeared to be appreciably 

 affected in the case of any of the cereals by the exposure to the extreme 

 cold of the liquid air, the temperature of which is approximately — 200° C. 

 No constant difference was noticeable between the effects of exposure in 

 sealed tubes and of exposure in muslin bags where the seeds were in direct 

 contact with the liquid air. 



The slight drop in the percentage germination after exposure to liquid air 

 in sealed tubes in the case of barley and rye, and in the case of wheat, oats, 

 and rye where the seeds were in direct contact with the liquid air, is 

 probably the result of these samples containing a few seeds whose power of 

 germination was at a low ebb. In any case the differences are very small, 

 and would be almost within the limit of error, were they not all on the same 

 side. 



As no means were available of obtaining lower temperatures, it was 

 impossible to arrive at the satisfaction of destroying the ferments by 

 abnormally low temperatures, if this be possible. Somewhat similar sets of 

 experiments were performed by Brown and Escombe * who kept various 

 kinds of seeds exposed to liquid air enclosed in vacuum- jacketed tubes for 

 110 hours, and then slowly thawed them. They proceeded to test the 

 germinating power of these seeds together with control specimens, but did 

 not discover any appreciable difference between that of the seeds which had 

 * 'Science,' N. Ser., vol. 8, 1898, p. 215. 



