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1790 MIGRATION OF BIRDS 219 



deny myself the honest satisfaction of offering you my 

 thanks : and I hope you will excuse the liberty that I have 

 taken. I have kept a poor imperfect journal above 50 years ; 

 but it has been chiefly confined to the leafing and growth 

 of trees ; and was undertaken by the advice of my most 

 estimable friend the late D**. Hales. By that I find that 

 Linnseus's disciples, and their followers, are mistaken in 

 their supposed rule of Nature, that all plants must follow in 

 order. For you see by the Indications of Spring in the last 

 Vol. of the Phil. Trans, which very imperfect as it is, the 

 R. S. did me the honour to print, there are reverses of many 

 days. 



Sir, I was much pleased with your Poetry in the Summer 

 Evening walk. — I hope you will excuse my asking you some 

 questions for my information. The copulation of Frogs as 

 you describe, is the manner of Toads with us: and I never 

 saw Frogs so engaged. 



By your account of the Swallows on the 29th of Sep., 

 1768, I presume that you believe in their migrating: and 

 there are very strong reasons to believe so of some other 

 Birds. Many Woodcocks are found by the Light-houses in 

 Norfolke in the Autumn, that are kilFd by flying against 

 the Lights: and the Earl of Orford informed me that the 

 Landgrave of Hesse sent him a ring taken from the leg of 

 an Heron with Ld. 0. name upon it. This is certain proof 

 of the Heron's going from England : and myself have seen 

 (coming from Holland) a Wagtail (Motacilla alba) flying 

 about the Ship, seemingly at ease, when out of sight of 

 Land. These, without Admiral Wager's, Adanson's and 

 Smith's, (the earliest account that I recollect in print) are 

 sufficient for migration: and the proofs for torpidity are 

 also undoubted. So we may conclude they are both true. 

 But the annual increase in the Swallow tribe, which are lost 

 in Winter, affords unaccountable difficulties to be cleared. 

 I have had 4 pair attending my house as many years as 



