ON THE PROGRESS OF AERONAUTICS. 
369 
unless it can be shown that means exist by which it could be 
increased sufficiently to bear a reasonable relation to the forces 
to which it is to be opposed.” 
Therefore the experiment which the society had advocated 
for several years, and which it had at last determined to adopt, 
having proved successful under disadvantageous circumstances 
when tried by others, the apparatus ordered was countermanded. 
The opinion which had been expressed also in the various 
reports issued by the society as to the inutility of any screw 
apparatus for effecting horizontal propulsion was confirmed. 
It is singular that no one has taken advantage of an ascer- 
tained fact to put the balloon to more pleasurable, because more 
prolonged use, than has hitherto been attempted. For instance, 
let us consider the mode of propulsion adopted in a punt — a 
clumsy kind of boat, which may often be seen moored in the 
Thames, in mid-stream, with harmless old gentlemen seated 
therein, alluring gudgeon. Well, these punts are cleverly 
managed with a long pole. In a rapid stream, should the 
punter wish to go with it, he has nothing to do but to keep it 
off from the bank, under the full influence of the stream ; and 
there is every probability that with a balloon so balanced a push 
with a long pole would send it up spinning for fifty feet or more, 
and one might traverse a few hundred yards before it neared 
the earth and required another push. The distance traversed 
between each push would of course depend upon the velocity of 
the air current. It is evident that no ballast is necessary under 
such conditions, therefore the absence of that would allow of 
reduced size of balloon. All this, however, is simply waftage. 
It is believed by some that the screw may yet serve a more 
useful purpose than that of the translation of a merely buoyant 
body. By muscular effort alone all that has been done by the 
power of one man has been the raising of 26 J lbs. weight. 
There has latterly been a more ambitious attempt, involving 
the expenditure of several hundred pounds of money. 
It resulted from the experiments which the Aeronautical 
Society instituted with a view to record for the benefit of inven- 
tors the exact lifting pressure due to the wind advancing against 
a plane inclined towards it at different angles. These experi- 
ments, which took place at Messrs. Penn’s factory, at Greenwich, 
were conducted by several well-known members of the council, 
and it was well understood at the time that if the results gave 
no encouragement for the attainment of success in utilizing the 
air as a highway, the society should be dissolved. 
Accordingly an instrument devised by Mr. Wenham was con- 
structed by Mr. Browning for the before-mentioned society, and 
submitted to a powerful blast from a fan-blower ten feet long 
by eighteen inches square. 
VOL. XV. — NO. LXI. B B 
