STUDY X. 373 



along the furface of the azure deep, and the fwan, 

 fleets of which navigate the extenfive lakes of the 

 North. 



There are likewife others which, in order to 

 form a contraft with thofe that I have laft men- 

 tioned, detach themfelves from the ikies and from 

 the waters, by their black, or dufky colours : fuch 

 are, for example, the crow, in our own climates, 

 which is perceptible at fo great a diftance in the 

 Heavens, on the white ground of the clouds ; many 

 fea-fowls of a brown and blackilh colour, as the 

 frigat of the Tropics, which plays through the air, 

 amidft ftorm and tempeft ; the mower, or fea-cut- 

 ter, a water bird, which grazes with his dark-co- 

 loured wings, fhaped like a fcythe, the white fur- 

 face of the foamy billows of the Ocean. 



From thefe examples, therefore, it may be in- 

 ferred, that when an animal is invefted with but 

 one fingle tint, he is intended but for one fitua- 

 tion ; and when he combines in himfelf the con- 

 traft of two oppofite tints, that he lives on two 

 grounds, the colours themfelves of which are de- 

 termined by that of the plumage, or of the hair, of 

 the animal. We muft be upon our guard, at the 

 fame time, againft an unlimited generalization of 

 this Law. We ought to confider it as harmoniz- 



B b 3 ing 



