MIGEATIOK. 135 



ttese thirty years past, in that part of the world. A mean 

 quantity in that connty for one year is twenty inches and a 

 half. 



LETTEE XLII. 



TO THE SAME. 



Fyfield, near Andover, Feb. 12, 1771. 

 Deab Sib, — Ton are, I know, no great friend to migra- 

 tion ; and the weU-attested accounts from various parts of 

 the kingdom, seem to justify you in your suspicions, that at 

 least many of the swallow kiad do not leave us in the 

 winter,* but lay themselves up like insects and bats, in a 

 torpid state, and slumber away the more uncomfortable 

 months, till the return of the sun and fine weather awakens 

 them. 



But then we must not, I think, deny migration in general; 

 because migration certainly does subsist in some places, as 

 my brother in Andalusia has fuUy informed me. Of the 

 motions of these birds he has ocular demonstration, for many 

 weeks together, both spring and fall ; during which periods, 

 myriads of the swallow kind traverse the Straits from north 

 to south, and from south to north, according to the season. 

 And these vast migrations consist not only of hirundines, 

 but of bee-birds, hoopoes, oro pendolos, or golden thrushes, 

 &c., &c., and also of many of our soft-bUled summer birds of 

 passage ; and moreover, of birds which never leave ne, such 

 as aU the various sorts of hawks and kites. Old Belon, 

 two hundred years ago, gives a curious account of the incre- 

 dible armies of hawks and kites which he saw in the spring 

 time traversing the Thracian Bosphorus, from Asia to 

 Europe. Besides the above mentioned, he remarks that 

 the procession is swelled by whole troops of eagles and 

 vultures. 



* See preceding note on this subject, page 39 of this edition. — Ed. 



