SOME AERONAUTK AL EXPEKIMENTS. 141 



of Teiincssei', un exjx'rieiiccd iioioiKiuticul iiivestij^ator in the ciiiploy 

 of Mr. Chanutc bv whom hiw servk-es were kindly h^incd, and l>y Dr. 

 G. A. Spratt, of Peinisylvania, a young nian who has math' ,sonie val- 

 ual)l(^ investigations of tlie properties of variously curved surfaces 

 and the trav(d of the center of pressure thereon. Early in August 

 Mr. Chanute came down from Chicago to witness our experiments 

 and spent a week in canlp with us. These gentlemen, witli my ))r<)ther 

 and myself, formed our cam})ing party, but in addition we liad in 

 many of our ex])eriments the valuable assistance of ^Jr. A\ '. ,) . Tate 

 and Ml-. Dan. Tate, of Kittyhawk. 



The machine was completed and tried for the first time on the 2Tth 

 of 'luly, in a wind blowing al)out 13 miles an hour. The operator 

 having taken a ])o.sition where the center of pressure was supposed to 

 be, an attempt at gliding was made, l)ut the machine turned downward 

 and landed after going onl}' a few 3'ards. This indicated that the 

 center of gravity was too far in fi'ont of the center of pressure. In 

 the second attempt the operator took a position several inches fartiier 

 back, but the result was nmch the same. lie ke|)t moving farther and 

 farther back wdth each trial, till tinally he occu})ied a position nearly a 

 foot l>ack of that at whicli we had expected to find the center of pressure. 

 The machine then sailed off and made an undulating flight of a little more 

 than 800 feet. To the onlookers this flight seemed very successful, ))ut 

 to the ()})erator it was known that the full power of the rudder had been 

 re([uired to keep the macliine from either running into the groimd or 

 I'ising so high as to lose all headway. In the IDOO machine one-fourth 

 as nmch rudder action had been sufficient to give nmch ])etter control. 

 It was apparent that something Avas radically wrong, though we Avere 

 for some time unable to locate the trouble. In one glide the machine 

 rose higher and higher till it lost all headway. This was the position 

 from which Lilienthal had always found difficulty to extricate himself, 

 as his machine then, in spite of his greatest exertions, manifested a 

 tendency to dive downward almost vertically and strike* the ground 

 head on with frightful velocity. In this case a warning cr}' from the 

 ground caused the operator to turn the rudder to its full extent and 

 also to move his l)ody slightly forward. The machine then settled 

 slowly to the ground, maiTitaining its horizontal position almost per- 

 fectly, and landed without any injury at all. This was very encourag- 

 ing, as it showed that one of the very greatest dangers in machines 

 with horizontal tails had })een overcome by the use of a front rudder. 

 Several glides later the same experience was repeated Avitli the same 

 result. In the latter case the machine had o\on commenced to move 

 backward, but was nevertheless brought safely to the ground in a 

 horizontal position. On the whole, this da^^'s experiments were 

 encouraging, for while the action of the rudder did not seem at all like 

 that of our 1900' machine, yet we had escaped without difficulty from 

 positions which had proved very dangerous to preceding experiment- 



