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OF THE 



MIGRATION 



O F 



BRITISH BIRDS. 



Quam multae glomerantur aves ! ubi frigidus annus 

 Trans pontum fugat, et terris immittit apricis. Virgil, 



^TpHE migration of birds, is a fubjec"t of fo curious 

 ■*> a nature, that every one who attempts to write 

 the natural hiftory of animals, ought to look upon it 

 as an eiTential part of his inquiries, and at the fame 

 time mould endeavour to aflign the caufe why fome 

 birds prefercertain places for their fummer, others, 

 for their winter refidence. 



To be qualified for this tafk, it is necelTary thac 

 the inquirer mould confine himfelf to one certain 

 traft the whole year ; he mould be diligent in ob- 

 ferving the arrival, and the difappearance of birds ; 

 he mould commit every obfervation to paper, and 

 compare them with the remarks of correfpondentsi 

 on the fame fubject, that lye on every fide of him. 

 He mould attend likewife to the weather •, and to the 

 2 plenty 



