THE METHOD OF HOMING PIGEONS. 



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dog. One of these, the devious path of a bright six-year-old Irish 

 girl, is reproduced in Fig. 12. Lubbock's ants might be pardoned 

 for smiling should they chance to see this tracing. 



The search line of an intelligent dog is given in Fig. 11. His 

 eyes were covered, but he evidently had a strong impression that 

 the ball had been thrown in the direction I happened to be fac- 

 ing. Resemblance between this and tracings of a number of the 

 pigeons is quite evident. 



The bearing of the above upon the problem of search as ex- 

 hibited by the homing pigeon requires no detailed statement. In 

 a word, the pigeon uses a logic of search which is common to ani- 

 mals generally, and there is no evidence that he employs any- 

 thing else. His power of rapid and prolonged flight makes it pos- 

 sible for him to spin his search lines over vast areas and so carry 

 them beyond our vision and lift them into the realm of mystery. 



In such cases the time consumed furnishes an important check. 

 Of a large number of birds sent away by rail for longer flights, 

 not one made the return trip in less time than would have en- 

 abled him to fly on the involute of a circle from the place of 

 liberation. This refers to "first flights." The best time made 

 was twenty-six miles in five hours and nine minutes. Three other 



birds liberated at the ^ _^ 



same time failed to 

 return. Letting the 

 distance to which a 

 prominent landmark 

 is visible be three 

 miles, a fair estimate 

 for pigeons with some 

 training and over 

 broken country, the 

 least length of an in- 

 volute of a circle 

 which would bring a 

 bird from a distance 

 of twenty-six miles 

 to within sight of the 

 loft is two hundred 

 and nineteen miles. 

 In five hours it is 

 not likely that the pigeon flew less than two hundred and fifty 

 miles. 



One thing which causes the search lines of the pigeons to 

 swerve from the ideal curve of search upon a uniform field is 

 that the field in their case is never uniform. A house of any 

 kind, especially a red building, or, upon the lake, nearness to land. 



,-\/ 





Fig. 10. 



Three search lines, circular and rectangular types. 

 + Starting point. The ball is shoivn at different 

 points on , the kO step circle. Fence. 



