CHAPTER VI. 



OUR FEATHERED ENGINEERS. 



IT is a well-known and profoundly interesting fact 

 that many of the crafts practised by civilised men, 

 as well as by savages, have been anticipated by 

 animals much lower in the scale of organisation. 

 We have many clever engineers and architects 

 among insects, and even among fishes. Ants, the 

 trap-door spider, the caddis, and the stickleback 

 are amongst the most familiar examples ; but in 

 the present chapter we propose to confine our 

 attention exclusively to the engineering capa- 

 bilities of birds. Every one is familiar with the 

 nests of birds. Even the most casual observer 

 cannot have failed to notice the big nests of the 

 Rooks high up in the lofty elms, the homes of the 

 House Sparrows on buildings and in trees, or the 

 curious cradle of the Martin attached to the walls 

 of houses under the eaves. All nests, however, 

 are by no means made on the same plan ; the 

 various raw materials are worked up in many 

 different ways. For convenience of treatment we. 

 will divide the various examples of bird archi- 



