NATURAL HISTORY OF SELBORNE 131 



After so much labor 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 

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

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

 engender, 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 fai/cia, 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 business of a second brood ; while the 

 first flight, shaken off and rejected by their nurses, congregate 

 in great flocks, and are the birds that are seen clustering and 

 hovering on sunny mornings and evenings round towers and 



