248 THE ZOOLOGIST. 



them — a head wind retards, a tail wind accelerates, beam winds 

 carry the machines out of their courses. These results agree in 

 every way with all the observations I have made on wild birds, 

 and are quite in keeping with all known natural laws. On the 

 other hand, they are in violent opposition to the popular " Head 

 Wind " theory of modern ornithologists, with its weird by-pro- 

 ducts of " feather-ruffling," and so forth : and I hold that this 

 latter theory was erroneous in the first place, and has never 

 during its existence received any support from checked and 

 tested observations. 



Perhaps I might offer the following as a help to those who 

 do not care to treat the problem theoretically. One day I saw, 

 during a " balloon race," two balloons at an altitude of 2000 ft., 

 travelling tandem, about half a mile apart. There was a good 

 wind, and the vessels were drifting across the surface of the 

 earth at about 60 miles per hour. The aeronauts, of course, 

 were unconscious of this wind ; the balloons, with their ropes 

 and hanging flags, were as rigid as though carved from metal ; 

 and there was the usual strange experience of standing in a 

 strong wind and seeing the yellow mist of the falling ballast in a 

 perfectly vertical column. The air around and between these 

 two balloons was certainly as calm as that of a vault. Now, let 

 us try and imagine a strong pigeon being released from the 

 second balloon, and flying in a straight line to the first, with a 

 velocity of 60 miles an hour. In 30 seconds it would have 

 covered the journey ; but, at the same time, the two balloons, 

 and the medium supporting them, would have travelled over 

 half a mile of the earth's surface. The speed of the bird, to the 

 terrestrial observer, would be therefore one mile in 30 seconds, 

 or 120 miles per hour. If we now imagine the bird returning to 

 the second balloon, it would complete its half mile of vigorous 

 flight and still remain precisely over the same spot on the earth. 

 According to the "head wind" ornithologists, it ought to be 

 moving at an enhanced speed across the earth under these 

 circumstances. Let us hope the theory has a champion ready 

 to come forward with calculation or observation explaining just 

 how it is achieved. 



