162 THE NATURAL HISTORY 



LETTER XXII 



TO THE HONOURABLE DAINES HARRINGTON 



Selborne, Sept. 13, 1774. 



DEAR SIR, 



BY means of a straight cottage-chimney I had an 

 opportunity this summer of remarking, at my leisure, 

 how swallows ascend and descend through the shaft ; 

 but my pleasure, in contemplating the address with 

 which this feat was performed to a considerable depth in 

 the chimney, was somewhat interrupted by apprehensions 

 lest my eyes might undergo the same fate with those 

 ofTob'it. 1 



Perhaps it may be some amusement to you to hear at 

 what times the different species of hirundines arrived this 

 spring in three very distant counties of this kingdom. 

 With us the swallow was seen first on April the 4th, the 

 swift on April the 24th, the bank-martin on April the I2th, 

 and the house-martin not till April the 3Oth. At South 

 Zele, Devonshire, swallows did not arrive till April the 

 25th; swifts, in plenty, on May the ist ; and house- 

 martins not till the middle of May. At Blackburn, in 

 Lancashire, swifts were seen April the 28th, swallows 

 April the 29th, house-martins May the ist. Do these 

 different dates, in such distant districts prove anything for 

 or against migration ? 



A farmer, near Weyhill, fallows his land with two teams 

 of asses ; one of which works till noon, and the other in 

 the afternoon. When these animals have done their work, 

 they are penned, all night, like sheep, on the fallow. In 

 the winter they are confined and foddered in a yard, and 

 make plenty of dung. 



Linnaeus says that hawks " paciscuntur inducias cum 

 avibus, quamdiu cuculus cuculat" : but it appears to me that, 

 during that period, many little birds are taken and destroyed 



1 Tobit ii. 10. 



