ORGASM AND IRRITABILITY 223 



torpid works this result by weakening their orgasm and hence by 

 slackening their vital movements. If this reduction of temperature 

 goes too far, I have already observed that it extinguishes the orgasm 

 and causes the death of the animal ; but I may remark on this subject, 

 with regard to the effects of cooling, not carried far enough to kill 

 the individual, that there is a certain peculiarity in the case of warm- 

 blooded animals and perhaps of all animals that have nerves : it is 

 as follows. 



It is known that no very great fall of temperature is required to bring 

 about the torpid state of apparent sleep in certain mammals, such as 

 marmots, bats, etc. If the heat returns, it penetrates, revives, awakes, 

 and restores them to their usual activity ; but if on the contrary 

 the cold increases still further after these animals have become torpid, 

 they do not pass imperceptibly from their condition of apparent 

 sleep into death. If the increase of cold is considerable, it causes an 

 irritation in their nerves which awakes and agitates them, and revives 

 their organic movements and hence their internal heat. If the increase 

 of cold then continues, it soon throws them into a state of disease, 

 ending in death unless heat is quickly restored to them. 



Hence it follows that, for warm-blooded animals and perhaps for 

 all animals with nerves, a mere weakening of their orgasm may reduce 

 them to a torpid state. In this case the orgasm is not totally destroyed, 

 since if the cold were great enough for that purpose, it would begin 

 by irritating them, giving them pain and end by killing them. 



In the case of animals without nerves, it seems that a reduction of 

 temperature sufficient to weaken their orgasm and make them torpid, 

 may if it increases result in their passing through their stage of lethargic 

 sleep to that of death, without any temporary return of activity. 



Those who imagine that the first result of a moderate degree of cold 

 is to slacken the respiration, have mistaken the effect for the cause. 

 Thus the torpid state, into which various animals fall when the tempera- 

 ture is lowered, has been attributed to a direct slackening of the 

 respiration of these animals ; whereas in point of fact the slackening 

 of respiration is itself due to another effect of the cold, namely, the 

 enfeeblement of their orgasm. 



As regards animals which breathe with lungs, those that fall into a 

 torpid state in certain degrees of cold doubtless undergo a considerable 

 slackening of respiration ; but here it is clearly only the result of a 

 great enfeeblement in their orgasm. Now this enfeeblement slackens 

 all the organic movements and all the functions. It diminishes also the 

 production of internal caloric and the losses which these animals are 

 subject to, during their customary activity. Their need for restoration 

 during their lethargy is thus very slight or next to nothing. 



