172 NATURAL HISTORY OF SELBORNE. 



Here are in this parish, in the sand-pits and banks of the lakes 

 of Woolmer forest, several colonies of these birds, and yet they 

 are never seen in the village ; nor do they at all frequent the 

 cottages that are scattered about in that wild district. The only 

 instance I ever remember where this species haunts any building 

 is at the town of Bishop's Waltham, in this county, where many 

 sand-martins nestle and breed in the scaffold-holes of the back- 

 wall of William of Wykeham's stables ; but then this wall stands 

 in a very sequestered and retired enclosure, and faces upon a large 

 and beautiful lake. And indeed this species seems so to delight in 

 large waters, that no instance occurs of their abounding but near 

 vast pools or rivers ; and in particular it has been remarked that 

 they swarm in the banks of the Thames in some places below 

 London-bridge. 



It is curious to observe with what different degrees of architec- 

 tonic skill Providence has endowed birds of the same genus, and 

 so nearly correspondent in their general mode of life! for while the 

 swallow and the house-martin discover the greatest address in 

 raising and securely fixing crusts or shells of loam as cunabula for 

 their young, the bank-martin terebrates a round and regular hole 

 in the sand or earth, which is serpentine, horizontal, and about two 

 feet deep. At the inner end of this burrow does this bird deposit, 

 in a good degree of safety, her rude nest, consisting of fine grasses 

 and feathers, usually goose-feathers, very inartifi daily laid together. 



Perseverance will accomplish anything ; though at first one would 

 be disinclined to believe that this weak bird, with her soft and 

 tender bill and claws, should ever be able to bore the stubborn 

 sand-bank without entirely disabling herself ; yet with these feeble 

 instruments have I seen a pair of them make great despatch, and 

 could remark how much they had scooped that day by the fresh 

 sand which ran down the bank, and was of a different colour from 

 that which lay loose and bleached in the sun. . 



In what space of time these little artists are able to mine and 

 finish these cavities I have never been able to discover, for reasons 

 given above ; but it would be a matter worthy of observation, where 

 it falls in the way of any naturalist to make his remarks. This I 

 have often taken notice of, that several holes of different depths are 

 left unfinished at the end of summer. To imagine that these be- 

 ginnings were intentionally made in order to be in the greater 

 forwardness for next spring is allowing perhaps too much foresight 

 and rerum prudentia to a simple bird. May not the cause of these 



