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THE WOOLWICH BALLOON ASCENT. 
By CAi*r. C. OKDE BROWNE. 
[PLATE CXV]. 
O N the 25th of July last a balloon experiment took 
place at Woolwich Arsenal which excited considerable 
interest. The object of the trial was to test a steering appa- 
ratus, designed by Mr. Bowdler, attached to a balloon which is 
the property of Mr. Coxwell, the Government supplying the gas 
and defraying the cost of the ascent. The trial was conducted 
under the personal direction of Major Beaumont, R.E., the 
president of the balloon committee. (See Plate CXV.) 
The experiment was one that naturally attracted attention, 
for the control of a balloon is at the same time one of the most 
difficult problems that has come before scientific men, and one 
that stands at the gateway of the path to any extended and 
systematic use of balloons. 
A few words will be sufficient to explain this to those who may 
not have studied the subject. 
The motion of a balloon, like that of a projectile or any other 
body in space, may be resolved into the horizontal and vertical 
directions ; that is, its horizontal motion as it travels over the 
earth may be viewed as altogether distinct from its rise or 
descent. It is not merely for analytical purposes that these 
components are thus separated ; they may be said to separate 
themselves, each one being due to the action of a perfectly dis- 
tinct cause, and each differing totally in its character from the 
other. 
The vertical, which is due to the difference in the specific 
gravity of the balloon taken as a whole and the air displaced by 
it, is clearly subject to control. The balloon may be made to 
rise by throwing out ballast, and to descend by expelling gas. 
This plan of operation, however, is attended by inconvenience, 
and is very limited in its scope. To understand this it may be 
well to trace the course of a balloon in its ascent. On leaving 
the earth it is necessarily only imperfectly filled, for to continue 
