426 BELL 



kite variety can be made ; and to the assembling of the ma- 

 terials for its manufacture. 



I have had to improve and simplify the method of making 

 the winged-cells themselves. Through the agency of Mr. 

 Hector P. McNeil, Superintendent of the Volta Laboratory, 

 Washington, D. C, who is now taking up the manufacture of 

 tetrahedral cells as a new business, I am now able to obtain 

 cells constructed largely by machinery, and with stamped-metal 

 corners to hold the rods together. The process of tying the 

 cells and parts of cells together had proved to be very labori- 

 ous and expensive ; and the process was not suited to unskilled 

 persons. By the new process most of the work is done by ma- 

 chinery, and no skill is required to connect the cells together. 



I have also had to go into the question of motor construction, 

 a subject with which I am not familiar ; and while waiting for 

 the completion of the material required for the aerodrome I have 

 been carrying on experiments to test the relative efficiency of 

 various forms of aerial propellers. I have also been occupied 

 with the details of construction of a supporting float adapted for 

 propulsion over the water as a motor boat, and also adapted to 

 form the body of the flying-machine when in the air. 



Of course it would be premature for me to enter into any 

 description of experiments that are still in progress, or to submit 

 plans for an aerodrome which are still under discussion. I shall 

 therefore simply say in conclusion that I have recently been 

 making experiments in propelling, by means of aerial propellers, 

 a life-raft supported, catamaran fashion, on two metallic cyl- 

 inders. The whole arrangement, with a marine motor on board, 

 is exceedingly heavy, weighing over 2,500 pounds; and it is 

 sunk so low that the water level rises at least to the middle of 

 the supporting cylinders, so that the raft is not at all adapted for 

 propulsion, and cannot attain great speed. The great and 

 unnecessary weight of this machine has led to an interesting 

 and perhaps important discovery that might have escaped atten- 

 tion had the apparatus been lighter and better adapted for pro- 

 pulsion. 



Under the action of her aerial propellers, this clumsy raft is 

 unable to attain a higher speed than four miles an hour; and yet 



