The Natural History of Se I borne 223 



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 

 small straws, grasses, and feathers, and sometimes by a bed of 

 moss interwoven with wool. In this nest they tread, or en- 

 gender, frequently during the time of building; and the hen 

 lays from three to five white eggs. 



At first, when the young are hatched, and are in a naked 

 and helpless condition, the parent birds, with tender assiduity, 

 carry out what comes away from their young. Was it not for 

 this affectionate cleanliness the nestlings would soon be burnt 

 up, and destroyed in so deep and hollow a nest, by their own 

 caustic excrement. In the quadruped creation the same neat 

 precaution is made use of; particularly among dogs and cats, 

 where the dams lick away what proceeds from their young. 

 But in birds there seems to be a particular provision, that the 

 dung of nestlings is enveloped in a tough kind of jelly, and 

 therefore is the easier conveyed off without soiling or daubing. 

 Yet, as nature is cleanly in all her ways, the young perform 

 this office for themselves in a little time by thrusting their tails 

 out at the aperture of their nest. As the young of small birds 

 presently arrive at their ^Ai/a'a, or full growth, they soon become 

 impatient of confinement, and sit all day with their heads out 

 at the orifice, where the dams, by clinging to the nest, supply 

 them with food from morning to night. For a time the young 

 are fed on the wing by their parents ; but the feat is done by 

 so quick and almost imperceptible a flight that a person must 

 have attended very exactly to their motions before he would be 

 able to perceive it. As soon as the young are able to shift for 

 themselves, the dams immediately turn their thoughts to the 



with an obviously insolent air of self-assertion. They seemed to say, 

 "Who's afraid of you? We mean to go on building in spite of you." In 

 the e"nd, however, we tired them out, and the house-martins returned to 

 undisturbed possession. ED. 



