The Philosophy of Birds' Nests. 419 



southern forest-clad country, and strikingly corroborate the 

 view derived from philology, that Greece was colonised from 

 north-western India. But to erect columns and span them 

 with huge blocks of stone or marble is not an act of reason, 

 but one of pure unreasoning imitation. The arch is the only 

 true and reasonable mode of covering over wide spaces with 

 stone, and, therefore, Grecian architecture, however exquisitely 

 beautiful, is false in principle, and is by no means a good 

 example of the application of reason to the art of building. 

 And what do most of us do at the present day but imitate the 

 buildings of those that have gone before us ? We have not 

 even been able to discover or develope any definite mode of 

 building best suited for us. We have no characteristic national 

 style, and to that extent are even below the birds, who have 

 each their characteristic form of nest, exactly adapted to their 

 wants and habits. 



That excessive uniformity in the architecture of each species 

 of bird which has been supposed to prove a nest-building 

 instinct we may, therefore, fairly impute to the uniformity of 

 the conditions under which each species lives. Their range is 

 often very limited, and they very seldom permanently change 

 their country so as to be placed in new conditions. When, 

 however, new conditions do occur, they take advantage of them 

 just as freely and wisely as man could do. The chimney and 

 house- swallows are a standing proof of a change of habit since 

 chimneys and houses were built, and in America this change 

 has taken place within about three hundred years. Thread and 

 worsted are now used in many nests instead of wool and horse- 

 hair, and the jackdaw shows an affection for the church steeple 

 which can hardly be explained by instinct. The Baltimore 

 oriole uses all sorts of pieces of string, skeins of "silk, or the 

 gardener's bass, to weave into its fine pensile nest, instead of 

 the single hairs and vegetable fibres it has painfully to seek in 

 wilder regions, and Wilson believes that it improves in nest- 

 building by practice — the older birds making the best nests. 

 The purple martin of America takes possession of empty gourds 

 or small boxes stuck up for its reception in almost every village 

 and farm in America, and several of the American wrens will 

 also build in cigar boxes, with a small hole cut in them, if 

 placed in a suitable situation. The orchard oriole of the 

 United States offers us an excellent example of a bird which 

 modifies his nest according to circumstances. When it is 

 built among firm and stiff branches it is very shallow, but 

 when, as is often the case, it is suspended from the slender 

 twigs of the weeping willow, it is made much deeper, so that 

 when swayed about violently by the wind, the young may not 

 tumble out. It has been observed also that the nests built in 



