438 BELL 



sand hills. On a day when there was little or no wind, they observed 

 a buzzard tobogganning down the atmosphere parallel to the sloping 

 sand and very near to it. Where the slope was steep enough the bird 

 could glide indefinitely without wing-beat, but where the incline was 

 too gentle, say seven degrees or less, the buzzard had to flap a little to 

 maintain its flight. Having carefully noted a considerable stretch of 

 sand where the bird could barely sail without flapping, they mounted 

 their glider and skimmed over the same slope without motive power. 

 From such experiments they concluded that they could glide fully as 

 well as the buzzard, and possibly a trifle better. In other words, if 

 they were placed on a perch with the bird in competition, in a large 

 closed room, they would probably win the prize for long distance 

 gliding. 



In one other feat, also, they imitated the vulture. They hovered 

 motionless above a sand slope for 59 seconds, neither rising nor fall- 

 ing, nor advancing nor receding. In this case, of course, the wind 

 had a slightly upward trend, say of seven or more degrees, just as 

 must be the case when any bird floats fixed and motionless in the air. 



I put this question to them recently : " After beating the buzzard in 

 the art of gliding, did you try to beat him in the art of soaring up to 

 the clouds? " They replied that nothing would have given them more 

 pleasure ; but their power machine, on which they had worked so 

 arduously, and so long, was ready for its first test, and Christmas was 

 just at hand. So they went out in a bitter gale, launched their motor 

 flying machine in the teeth of a tumultuous thirty-mile wind, and flew 

 half a mile through the air, or three hundred and some feet over the 

 ground. Thus ended their gliding and thus began their dynamic flight. 



But they still envy that feathered professor of the atmosphere, and 

 still have confidence that they may, to some extent, acquire his fasci- 

 nating art. If they could dispose of their present power machine, 

 doubtless they would return again to the sand-hills and plunge pell- 

 mell into the soaring business. 



As to the fourth type, or the motor flying-machine, I need add little 

 to the excellent summary given by Dr. Bell. Without radical improve- 

 ment, such machines may be driven through the air with the speed of 

 the eagle, and made to carry several hundred pounds burden. The 

 Wright brothers, in their recent communication to the Aero Club of 

 America, conclude with these words : " It is evident that the limits 

 of speed have not as yet been closely approached in the flyers already 

 built, and that in the matter of distance the possibilities are even more 

 encouraging. Even in the existing state of the art, it is easv to design 



