NO. 3 APPENDIX 293 



F. A. Lucas, Mr. N. R, Wood, and Mr. R. I,. Reed. Mr. Bolmes superintended 

 the experiments in connection with No. a (finding flic bird's center of gravity), 

 and by his suggestions ami criticisms helped me in many other particulars. The 

 photographs and enlargements were made by Mr. T. W. Smillie. 



Respectfully submitted, 



RoLLA P. CUBBIE, 



Aid, Division of Insects, acting in the Division of Birds. 



October 16, 1900. 



The feats of airmanship performed by the " John Crow " seemed to greatly 

 impress Mr. Langley and shortly after this trip he wrote the following letter to 

 the writer: 



Smithsonian Institution- 

 Washington, D. C, April 10, 1900. 

 Dear Mr. Manly : 



I am reminded of the consequence that I have, in connection with Mr. 

 Chanute and perhaps Mr. Huffaker, attached in the past to the possibilitj of 

 directing the bird, and consequently the flying machine, by the mere inflection of 

 the wing, that is, by changing its angle; and yen recall to me that Mr. Huffaker 

 at one time proposed to arrange a wing, with some provision of a spring, which 

 should enable it to change its angle automatically 



I have been noting this ability to guide by the slight inflection of the wing, 

 in my studies of the Jamaica buzzard, and am ready to say that I think, while 

 the quarter-sized working model of the great aerodrome is building, it will be 

 worth while to make some arrangement of the frame or wing-holder which will 

 make it possible to test this idea. I will endeavor to work out something of the 

 kind more in detail myself, but whatever it is, it will apparently involve the 

 ability of the wing to rotate about a line passing nearly through it lengthwise, 

 and an allowance for this; if not in the wing itself, then in the wing-holder; 

 will need to be made while the present model is under construction. 



I will request you to especially look out for this, as far as you can on these 

 indications. 



Very respectfully yours, 



S. P. Langley, 

 Secretary. 



The instructions and suggestions contained in this letter and in many con- 

 ferences on the subject were never carried out by the writer, on account of the 

 extreme pressure of the work already on him which had for its object, not the 

 production of a flying machine which would embody all of the control which we 

 wished it to have, but which would be burdened only with such devices and 

 arrangements as would enable it to transport a human being, and thus demon- 

 strate the practicability of human flight. 



