THE SPARROW KIND. 281 



loud singular noise, like the whirr of a spinning- 

 wheel. To this also belongs the House Swallow, 

 which is too well known to need a description : 

 the Martin, inferior in size to the former, and the 

 tail much less forked ; it differs also in its nest, 

 which is covered at top, while that of the house 

 swallow is open : and the Swift, rather larger than 

 the house swallow, with all the toes standing for- 

 ward, in which it differs from the rest of its kind. 

 All these resemble each other so strongly, that it 

 is not without difficulty the smaller kinds are 

 known asunder. 



These are all known by their very large mouths, 

 which when they fly are always kept open ; they 

 are not less remarkable for their short slender 

 feet, which scarce are able to support the weight 

 of their bodies ; their wings are of immoderate 

 extent for their bulk ; their plumage is glossed 

 with a rich purple ; and their note is a slight 

 twittering, which they seldom exert but upon the 

 wing. 



This peculiar conformation seems attended 

 with a similar peculiarity of manners. Their 

 food is insects, which they always pursue flying. 

 For this reason, during fine weather, when the 

 insects are most likely to be abroad, the swallows 

 are for ever upon the wing, and seem pursuing 

 their prey with amazing swiftness and agility. 

 All smaller animals, in some measure, find safety 

 by winding and turning, when they endeavour to 

 avoid the greater ; the lark thus evades the pur- 

 suit of the hawk, and man the crocodile. In 

 this manner, insects upon the wing endeavour to 



