OF NATURE. 241 



pearance of a fine day or two at this late 

 season of the year. Again, very early in the 

 Spring, and sometimes immediately after 

 very cold severe weather, on its growing a 

 little warmer, a few of these birds sud- 

 denly make their appearance, long before 

 the generality of them are seen. These 

 appearances certainly favour the opinion of 

 their passing the Winter in a torpid state, 

 but do not absolutely prove the fact ; for 

 who ever saw them reviving of their own 

 accord from their torpid state, without 

 being first brought to the fire, and as it 

 were, forced into life again; soon after 

 which revivification they constantly die. 



MARKWICK. 



SWALLOWS, CONGREGATING, AND 

 DISAPPEARANCE OF. 



During the severe winds that often pre- 

 vail late in the Spring, it is not easy to say 

 how the hirundines subsist : for they with- 

 draw themselves, and are hardly ever seen, 



VOL. IT. 3, 



