WINDOW SWALLOW. 



551 



pear, 1 have no hesitation in pronouncing it to be altogether fabu- 

 lous. Swallows, I admit, may be frequently seen both drinking 

 and washing- on the wing-, and also collecting mud from cart-ruts 

 and other places ; but never carrying water in their bills, or on 

 their feathers, neither of which are they capable of performing ; for 

 they want the necessary muscles to carry water in their mouths as we 

 can do, and whatever water might adhere to their feathers, would be 

 instantly shaken off in flying, let the dust, which requires sprinkling, 

 be as near as it might, for, according to my observation, it runs off 

 from them as it does from the feathers of ducks and other water fowl. 

 Besides their not being able to find materials sufficiently moist, is a 

 supposition altogether gratuitous and improbable, with respect to a bird 

 of such powerful wing, whose flight is so excursive, and usually in the 

 vicinity of water. 



That some liquid is requisite, however, to make their mortar more 

 adhesive, will be evident to any person who will take the trouble of 

 picking up a little mud from the same place where the swallows collect 

 it, and trying to make it adhere to a wall as they do in their nests. I 

 have more than once tried such an experiment without success, and 

 have thence been led to conclude that the swallows employ some sali- 

 vary fluid besides the water which may be in the mud. That this is 

 the fact, and not a fancy, may be easily proved, as it is, in numerous 

 instances ; and it is not adverting to this, that the building of nests 

 has been so ill understood by naturalists, and so many fanciful accounts 

 of the matter have been promulgated. I have further ascertained, by 

 examining nests during the process of building, that the portion of 

 clay just added, is considerably more moist than that of the ruts from 

 which it has been taken, a stronger proof that the bird moistens it 

 with saliva, than is afforded by merely finding larger salivary glands, 

 which is proved by dissection to be the case. 1 



Pennant says he has seen them build in cliffs overhanging the sea. 

 I am acquainted with one locality where they build in a similar man- 

 ner, at the beautifully romantic dell of Hawford, near Catrine, in 

 Ayrshire, where the river Ayr winds among wooded rocks, from one 

 to three hundred feet above its channel. There the nests are few in 

 number, and not crowded together, but scattered singly among the 

 cliffs. In this country, at least, the species is only subgregarious, par- 

 ties of some three, four, or half a dozen, selecting the same window or 

 several windows on the same frontage. The greatest number I ever 



Architecture of Birds. Chap, on Mason Birds, p. 101. 



