18 NATURAL HISTORY 



But as that short warm period was suc- 

 ceeded as well as preceded by harsh severe 

 weather, with frequent frosts and ice, and 

 cutting winds, the insects withdrew, the 

 tortoise retired again into the ground, and 

 the swallows were seen no more until the 

 tenth of April, when, the rigour of the 

 Spring abating, a softer season began to 

 prevail. 



Again; it appears by my journals for 

 many years past, that house-martins retire, 

 to a bird, about the beginning of October ; 

 so that a person not very observant of such 

 matters would conclude that they had 

 taken their last farewell : but then it may 

 be seen in my diaries also that consider- 

 able flocks have discovered themselves 

 again in the first week of November, and 

 often on the fourth day of that month only 

 for one day ; and that not as if they were in 

 actual migration, but playing about at their 

 leisure and feeding calmly, as if no enter- 

 prize of moment at all agitated their spirits. 

 And this was the case in the beginning of 

 this very month ; for, on the fourth of No- 



