House- 



U* . . A few house-martins begin to appear about the 



About the middle of May, if the weather be fine, 

 the martin begins to think in earnest of providing a. mansion for its 

 family. 



The crust or shell of this nest seems to be formed of such dirt or 

 loam as comes most readily to hand, and is tempered and wrought 

 together by little bits of broken straws, to render it tough and 

 tenacious. As this bird often builds against a perpendicular wall, 

 without any projecting ledge under it, it requires its utmost efforts 

 to get the first foundation firmly fixed, so that it may safely carry 

 the superstructure. On this occasion the bird not only clings with 

 its claws, but partly supports itself by strongly inclining its tail 

 against the wall, making that a fulcrum ; and, thus steadied, it 

 works and plasters the materials into the face of the brick or stone. 

 But then, that this work may not, while it is soft and green, pull 

 itself down by its own weight, the provident architect has prudence 

 and forbearance enough not to advance her work too fast ; but, by 

 building only in the morning, and by dedicating the rest of the day 

 to food and amusement, gives it sufficient time to dry and harden. 



In about ten or twelve days is formed an hemispheric nest, with a 

 small aperture towards the top strong, compact, and warm, and 

 perfectly fitted for all the purposes for which it was intended. 



But, then, nothing is more common than for the house-sparrow, 

 as soon as the shell is finished, to seize on it as its own, to eject the 

 owner, and to line it after its own manner. 



After so much labour is bestowed in erecting a mansion, as nature 

 seldom works in vain, martins will breed on, for several years 

 together, in the same nest, where it happens to be well sheltered, 

 and secure from the injuries of weather. 



The shell, or crust, of the nest is a sort of rustic-work, full of 



knobs and protuberances on the outside ; nor is the inside of those 



that I have examined smoothed with any exactness at all ; but 



is rendered soft and warm, and fit for incubation, by a lining of 



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