THE CLIFF-SWALLOW. 39 



dilection for the abodes of man, by building against' 

 the walls of houses, immediately under the eaves of 

 the roof, though they have not in the least changed 

 their style of architecture. A nest from the latter 

 situation is now before me : it is hemispherical, five 

 inches wide at its truncated place of attachment to 

 the wall, from which it projects six inches, and con- 

 sists exclusively of a mixture of sand and clay, lined 

 on the inside with straw and dried grass, negligently 

 disposed for the reception of the eggs. The whole 

 external surface is roughened by the projection of 

 the various little pellets of earth which compose the 

 substance. The entrance is near the top, rounded, 

 projecting, and turning downward, so that the nest 

 may be compared to a chymist's retort, flattened on 

 the side applied to the wall, and with the principal 

 part of the neck broken off. So great is the indus- 

 try of these interesting little architects, that this 

 massive and commodious structure is sometimes 

 completed in the course of three days."* 



White of Selborne thus describes the building 

 process of the window-swallow, or martin (Hirundo 

 urlica). "About the middle of May," he says, "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 with little 

 bits of broken straws to render it tough and tena- 

 cious. As this bird often builds against a perpen- 

 dicular wall without any projecting ledge under, it 

 requires its utmost eiforts to get the first foundation 

 firmly fixed, so that it may safely carry the super- 

 structure. 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 

 * Bonaparte, Amer. Ornith., i., 67. 



