WILD LIFE OF ORCHARD AND FIELD 



the same bird there a second time and none of 

 these aerial revolutions will occur — its time is too 

 pressing, its homesickness too intense for that; 

 instantly it turns its face towards its owner's 

 dove-cot. 



These facts mean something. They show that 

 two definite intellectual processes serve to decide 

 for the bird the direction he is to take — observation 

 and memory. He gets high enough, and turns 

 about times enough, to catch sight of some famil- 

 iar object, and he makes for it ; arrived there, an- 

 other known feature catches his eye, and thus by 

 ever narrowing stages he is guided home. Few 

 persons have any idea of the distance one can see 

 at great elevations. More than once I have stood 

 on the Rocky Mountains, where, had I been a pig- 

 eon, I could have steered my flight by another moun- 

 tain more than one hundred miles distant. Bal- 

 loonists say that at the height of half a mile the 

 whole course of the Thames or the Seine, from end 

 to end, is spread out as plain as a map beneath 

 their eyes. There is no doubt that a pigeon may 

 rise to where he can recognize, in clear weather, 

 a landscape one hundred and fifty miles away; it 

 has been done repeatedly, though only by the best 

 birds, specially trained for that particular line of 



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