TORPIDITY. 65 



body defended from the increasing cold and the action of 

 the air, will probably never be determined by satisfactory 

 experiments. Partial torpor has often been experienced in 

 the hands and feet, which is easily removed by a gradual 

 increase of temperature. We may add, that, in the case of 

 persons exposed to great cold in elevated situations on 

 mountains or in balloons, there are other causes in operation 

 which may have a tendency to produce sleep. The previ- 

 ous exertions have reduced the body to a very exhausted 

 state the pressure of the atmosphere is greatly diminished, 

 and the air inhaled by the lungs is rarified. 



When the animals now under consideration are regu- 

 larly supplied with food, and kept in a uniform tempera- 

 ture, it has been observed that they do not fall into their 

 wonted lethargy, but continue lively and active during the 

 winter season. This experiment has often been repeated 

 with the marmot and other animals. But when in this state 

 they are peculiarly sensible to cold. Dr REEVES, in some 

 experiments which he performed, says, " When I was in 

 Switzerland, I procured two young marmots in September 

 1805, and kept them with the view of determining the 

 question, whether their torpidity could be prevented by an 

 abundant supply of food and moderate heat. I carried 

 them with me to Vienna, and kept them the whole of the 

 winter 1805-6. The months of October and November 

 were very mild. My marmots ate every day turnips, cab- 

 bages, and brown bread, and were very active and lively : 

 they were kept in a box filled with hay in a cellar, and 

 afterwards in a room without a fire, and did not shew any 

 symptoms of growing torpid. December the 18th, the 

 weather was cold, and the wind very sharp ; FAHRENHEIT'S 

 thermometer stood at 18 and 20. Two hedgehogs died, 

 which were kept in the same room with the marmots ; and 

 a hamster died also in a room where a fire was constantly 

 VOL. ir. E 



