AND ANIMAL LIFE. 171 



CLXXXVIII. As the nature and influence of 

 those changes which predispose to or precede tor- 

 pidity were found to be the application of cold 

 and the diminution of temperature, the nature and 

 influence of those changes which predispose to, or 

 precede the return to active life, will consequently 

 be found to consist in the application of warmth 

 and the increase of temperature. 



CLXXXIX. It is not improbable that the 

 system thus emaciated by the evolution of unes- 

 sential matters from the lungs, may become more 

 susceptible to external agents, or uneasy sensa- 

 tions may be excited, the tendency of which is 

 to accelerate the respiration by the slight de- 

 grees of muscular exercise occasioned. But not 

 wishing to indulge in hypotheses, I shall leave 

 the consideration of this point to others. 



CXC. In the months of March and April, 

 the greater number of hibernating animals revive ; 

 and it is at this season of the year that vegetation 

 shows symptoms of returning vigour, from the mil- 

 der state of the atmosphere and the influence of the 

 solar rays. It is imagined by some, that the barns, 

 caves, and holes in the ground, to which these 

 animals have retired, prevent them from feeling 

 the beneficial agency of spring. Dr FLEMING 

 says, (( It cannot be owing to any considerable 

 change of temperature ; for their situation pre- 

 vents them from experiencing such vicissitudes."* 



* Vol. II. p, 69. 



