320 HOMES WITHOUT HANDS. 



the advantage they were enjoying. The space above the board, 

 and within the arched handle of the basket, was only inferior to 

 the basket itself as a situation for a nest, and there, accordingly, 

 they proceeded to place it. It was formed of clay, in the usual 

 manner, and here, immediately above their neighbours, they suc- 

 cessfully hatched their young. . . . The laying hold of a novel, 

 but obvious convenience, to secure an important object, is not 

 the least of the operations of the reasoning powers." 



The writer of this notice is quite correct in attributing the 

 performances of these birds to reason, and not to instinct. 

 Instinct would have taught them to make their nests under 

 ordinary conditions, and to raise their clay-built houses against 

 a wall But the mental process which led them to accommodate 

 themselves to such a change of circumstances as the substitution 

 of a basket for a wall does, undoubtedly, belong to the province 

 of reason, rather than of instinct. 



To examine minutely the economy of a Martin's nest is a 

 pleasant task enough, but has its drawbacks, which are veiy 

 numerous, and may be summed up in one word — vermin. 



All birds are liable to the attacks of parasitic insects, but the 

 Martins contrive to harbour such quantities of them that the 

 spectator cannot but wonder how they contrive to live through 

 the constant attacks. The nest itseK swarms with them, and 

 so numerous are their hosts that I have found an isolated lump 

 of clay filled with these repulsive insects, though at the distance 

 of eighteen inches from the nest. They are not visible at first, 

 and but for their cast skins would probably attract no notice. But 

 when one of these innocent-looking pieces of mud is removed, and 

 put under a glass in which a few drops of spirits of turpentine 

 have been placed, the vermin come trooping out of every crevice, 

 many in numbers, large in dimensions, and obese in outline. 



In one lump of clay about as large as a walnut, I have seen 

 so many parasites that they seemed capable of devouring all the 

 little birds ; and when it is remembered that every portion of the 

 nest is equally tenanted, how the inmates can survive for a 

 single night is indeed matter of surprise. Their size is absolutely 

 portentous ; for when compared with the birds on which they 

 feed, they are as large as full-grown frogs compared with men. 

 I mention this circumstance in order that my readers may be 

 chary of bringing a Martin's nest into a room, for to introduce 



