156 THE POPULAR SCIENCE MONTHLY 



a window or heating device, but the door into the laboratory was open a 

 part of every day. While the closet was dark the animal slept; when 

 lighted, it was active for several hours a day, but always went to sleep 

 when the early shadows began to fill the room. On the back of the cage 

 there was a small door which was fastened by a pivot and opened by 

 lifting one corner. It was not long until the little creature learned to 

 open the door and forage for himself. His curiosity was insatiable and 

 he climbed all over every part of the laboratory and carried back to his 

 cage everything he could find in the way of food, as well as a quantity 

 of rags kept for cleaning laboratory apparatus, but which he used to 

 make a nest for himself. 



His quarters were, of course, warmer than those of his brothers out 

 of doors and I at first thought that he would not hibernate, but the 

 heat was allowed to go down over Saturday and Sunday and in De- 

 cember when the temperature fell below zero outside, the room tem- 

 perature reached freezing point or lower. The first time this happened, 

 I missed the customary recklessness of my little pet on Monday and at 

 first thought that he had escaped or was dead. But a closer examina- 

 tion showed that he was asleep inside the mass of cotton, rags and 

 paper that composed his nest and with a heap of half-eaten kernels of 

 corn by his nose. His body felt cold, and lay inert in my hand when I 

 unwrapped him and I put him back again after covering him up as he 

 was before, but did not fasten the door he had learned to open. The 

 next morning I gave him no attention and it is difficult to say which 

 was discomfited the most, myself or the class, when he scuttled across 

 the laboratory floor and under a table where four girls were working, 

 paused to sniff at some seeds that had been dropped by a class in botany 

 and then darted to a well-known place of concealment behind a large 

 stationary cupboard. 



He did not take another prolonged sleep until I left for the Christ- 

 mas holidays. During vacation the fire was again allowed to go down 

 until there was just sufficient to keep steam pipes from freezing, and 

 I was not surprised to find him dormant at my return. This time I de- 

 termined to allow him to continue his winter's rest, so I kept the only 

 door of the closet shut and the temperature remained fairly constant 

 at a few degrees above freezing, perhaps falling to freezing point on 

 Saturday and Sunday, for the walls separating the closet from the ad- 

 joining rooms were thin and the temperature within them changed 

 slowly. Under these conditions, the sleep was prolonged somewhat more 

 than a month and its termination coincided with a period of warmer 

 weather. However, that did not end the hibernation of the animal, for 

 several times afterward he slumbered soundly for a few days at a time. 

 Each time he awoke he ate heartily and was quite active. When asleep 

 it was possible to awaken him by taking him up into the hands and 

 stroking him or handling him roughly. 



