NEW LIGHTS ON THE PROBLEM OF FLYING. 755 



Chicago at the World's Congress of Aeronautics. This model 

 was fifteen feet long, with two transverse aeroplanes forty feet 

 from tip to tip. Whether it was so exhibited or not I do not know. 

 Maxim, it is said, is now constructing a flying machine on a large 

 scale in London, but has not attempted yet to launch it. In both 

 of these the aeroplane slightly inclined is the main reliance for 

 sustaining when once in motion ; so that the whole power of the 

 engine and propellers is concentrated on rising and progress 

 through the air. 



Now, in the light of these experiments, what may we reason- 

 ably expect in the near future ? 



There are many difficulties in the way of success, which, of 

 course, these men clearly see and will try to provide for. These 

 are mainly three, viz. : (1) Difficulty of rising ; (2) stability in 

 progress ; and (3) safety in alighting. We take these in succession. 



1. RISING. Every word I have said in my previous paper, 

 only modified as to limit of weight, applies here still and with- 

 out abatement. It seems to be impossible for any machine, nat- 

 ural or artificial, of greater weight than at most a few hundred 

 pounds, to lift itself straight up in the air, or even to maintain 

 itself in the same place like a hovering bird, by the force of pro- 

 pellers alone and without the aid of a balloon. Therefore, there 

 must be some device other than, or in addition to, propellers to 

 raise the machine in the act of starting. But observe, I said 

 straight up. Many birds can not rise so. They must rise at very 

 gentle incline. They must get onward motion before their wings 

 can get full effect on the air. It is said that the mode of taking 

 the condor is to build a pen, say, forty to fifty feet in diameter 

 and six feet high, and put a carcass in the middle of it. The con- 

 dor alights, but can not again rise at an angle which will take 

 him over the fence. Many heavy -bodied, short- winged ducks rise 

 from the water at so small an angle that they must use both feet 

 and wings for thirty to forty feet in order to get onward motion 

 enough to give effectiveness to their wings by coming in contact 

 with larger masses of still air, as already explained. It follows, 

 therefore, that the flying machine must have some station device 

 to start it. It may be an elevator, but more probably it will be 

 machine rollers on a railway. With aeroplane spread and slightly 

 inclined and propellers directed a little backward, velocity might 

 be got sufficient to sustain and finally with the help of the pro- 

 pellers to raise the machine. As far as I can learn, this is the 

 plan of Maxim. 



Viewed in the light of the new principle, there is certainly 

 nothing impossible in this. But every machine is liable to acci- 

 dents. It is absolutely necessary that we should be able to stop 

 and go on again. Suppose in mid-flight anything should go 



