AERONAUTICAL WORE. 47 
was of the gentlest description. D was the most difficult kite to 
haul down. ‘The kite line used is common Manilla clothes line, 
and is not easy to handle when strained. A small winch on the 
sling seat will make an ascent possible without any assistance 
whatever. 
From experiments previously made with the three cornered 
calico kite in Plate 4, it is gathered that an increase in the velocity 
of. the wind on this occasion would have brought A, B and D 
nearer and nearer to the zenith, when a point would have been 
reached where the kites and line would begin to lean over side- 
ways and come nearer to the ground, making @ considerable 
azimuthal angle with the direction of the wind. Supposing the 
twenty-one mile wind to have a force of two pounds per square 
foot : then two hundred and thirty-two square feet of kite at 15° 
slope would exert a lift of two hundred and seventeen pounds and 
a drift of fifty-eight pounds. If the line were moved further for- 
ward so that the slope became 10°; an equa! velocity of wind would 
only produce one hundred and fifty-three pounds of lift, and the 
drift would be reduced to twenty-seven pounds. So that, if the 
kites are merely to lift weight, the line might with advantage be 
moved aft. If the kites are to be driven by a motor on board the 
lowest one, the weight must be moved forward when the thrust 
of the motor exceeds the drift. 
It is thought that this experiment marks an epoch in the series 
of aeronautical contrivances recorded in our Journal. Although 
the altitude attained was trifling, the conditions would be identical 
if the kites had been held by a mile of piano wire instead of 
the clothes line. 
The particular steps gained are the demonstration that an 
extremely simple apparatus can be made, carried about, and flown 
one man ; and that a safe means of making an ascent with a 
flying machine, of trying the same without any risk of accident, 
and descending, is’ now at the service of any experimenter who 
Wishes to use it, 
