158 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 



these pupils, the Comte de Lambert, now understands the working 

 of the apparatus, but always makes his flights in company with 

 Wright, who has not yet dared let him fly alone.« It is true that 

 with this type of machine, there must be accuracy of manipulation 

 out of the ordinary to avoid ever-possible accidents. It is to be 

 noted also that the Wright machines have not yet flown elsewhere 

 than over open fields. 



As to the cost of the machines, it is at once evident that aeroplanes 

 will be much less expensive than automobiles, for all that an aeroplane 

 needs are surface areas of cloth "or of aluminum, a motor, and a pro- 

 peller. There are no complicated gears made of special steel, for 

 changing the speed and the differential, and there are no expensive 

 pneumatic tires. 



A machine of the Wright and Voisin model now costs 20,000 francs, 

 or about $4,000, but this price may be lowered. Competition will 

 contribute to reduce the cost and we already have manufacturers who 

 undertake to furnish machines to be delivered after trial for 5,000 

 francs, or $1,000. I believe that this will be the common price for 

 most aeroplanes in the future. In order, however, that aeroplanes 

 may be of reasonable cost, there must be a demand for them, and to 

 create a demand there must be a need for them. 



From now on, from the point of usefulness, it is evident that flying 

 machines wnll render extraordinary service. They will permit direct 

 and rapid transportation anywhere, and one need no longer hesitate 

 to visit lands that to-day are difficult of access.'' * * * Direct 

 transportation is evident for there are no obstacles in the way ; but as 

 to the possible speeds to be attained, that is an open question. 



It is certainly possible to obtain very great speeds with an aero- 

 plane. The action of an illimitable force, that of gravity, is at our 

 disposal as soon as the machine is lifted above the ground, and 

 it is always possible to convert into speed the accumulated potential 

 energy, which is proportional to the weight of the machine and the 

 altitude attained. 



At the present time the machines do not rise high enough to apply 

 this method of conversion of power. They move forward only 

 through the speed of their propellers. Bleriot has thus reached 76 

 kilometers an hour, and Farman 78 kilometers an hour. These are 

 medium speeds. Bleriot has attained on certain occasions speeds 

 greater than 100 kilometers an hour. During the year 1909 we shall 

 certainly realize the speed of 200 kilometers an hour, and ten years 



" Lambert has since flown perfectly alone. Tissandier is a master and has 

 flown for more tban an hour; Capt. de Girardville as well, and Delagrange is 

 learning. 



* Hubert Latham is learning aviation to explore Africa. — June, 1909. 



