BALLOONING, MODERN. 



77 



with ooal gas is mmlc from an opening in any 



mail! I liul is hiru'e enough In give a suffl- 



flow in tho desired length nf time. Small 



mum*. <>r thusr ut considerable distance from 



il<~. will, as a rule, deliver the gas too 



-i ult> nny question regarding time 



<! for olitHiiiing u given quantity at any 



[...int. make ii test with a small balloon, of 500 



feet rimarity, noting the time required to 



till it. and calculate accord inglv. 



llulrogpn Inflation. Hydrogen gas for bal- 

 loon* inflation is made by the decomposition of 

 v\.i;.-r with the aid of sulphuric acid And fine 

 iron. Large wooden tanks, hogsheads, or bar- 

 rels are used fur the process, into which the iron 

 and water are first introduced, and when the acid 

 is added the generation immediately begins. Two 

 hundred and fifty pounds of acid, the same quan- 

 tity of fine iron, and 1,000 pounds of water are 

 required for each thousand cubic feet. The gas 

 - through pipes to a washer, and is made to 

 Dttbble up through lime water, after which it 

 passes through a flexible -conductor to the bal- 

 loon. Hydrogen gas will lift, according to its 

 purity, from 60 to 70 pounds for each thousand 

 cubic feet. 



The balloon is prepared for inflation by exten- 

 sion at full length, folding the breadths one upon 

 another,' and then equally dividing the leaves 

 so that they shall he in fan-like fashion two 

 breadths wide. With the neck of the balloon 

 toward the gas apparatus, it is to be covered with 

 canvas two thirds of the way from the neck to 

 the valve, and on this canvas, close to the bal- 

 loon, sand bags are arranged to prevent the folds 

 expanding with the gas, except at the upper end. 

 As the inflation progresses, the bags nearest to 

 the filled portion are removed one by one. The 

 net is spread over the top, and fastened round 

 the valve, and then the gas is allowed to flow 

 through to the valve end. A large bulb soon 

 forms, the head of the balloon rises, the net is 

 adjusted, and sand bags are hooked on to keep 

 all in place, chang- 

 ing them to lower 

 positions as the work 



Progresses, until 

 nally the globe is 

 completely distend- 

 ed. In the mean 

 time the car may be 

 attached by tying 

 the net cords to the 

 concentrating ring ; 

 some sand bags may 

 be put into the car, 

 those on the netting 

 allowed toslide along 

 the net ropes, and on 

 reaching the concen- 

 trating ring ropes 

 may be removed al- 

 together. The anch- 

 or and drag rope 

 must be neatly coiled 

 and hung on the side of the car, while their ends 

 are to be fastened to the cross loops overhead. 

 The anchor should be hung by its flukes to the 

 side of the car, and may be lashed to its place 

 until needed. Extra clothing, water, and provis- 

 ions are next in order, and then the aeronaut is 



ready to be off. Sand bags are removed one at 

 a time Until the car float .- and it* held by a Hingle 

 rope. This is then cast off, and the v<.\a. 

 gins. 



The Voyage. A sufficient buoyancy must be 

 given to clear all projections. The gas expands 

 as it rises in an atmosphere of increasing rarity, 

 and soon begins to be ejected from the open neck 

 of the Imllnnn. The loss, under a cloudy sky, 

 mav stop the ascent, but in bright sunshine the 

 balloon, floating in a relative calm, will become 

 heated to the extent of gaining many additional 

 pounds of ascensive power, and, in spite of the 

 continued loss, will keep rising until there is no 

 further gain in heat ; then a descent occurs, which 

 can only be overcome by the discharge of bal- 

 last. A voyage in the day-time usually consists 

 of a series of ascents and descents, because of the 

 alternate overflow of gas and discharge of bal- 

 last ; but at night this is all changed ; for a good 

 gas-tight balloon may be suspended at one con- 

 stant neight all night long. The reason of this 

 is that there is a decrease of temperature at the 

 rate of one degree for every four hundred feet, 

 and as cold condenses gas, making it heavier, it 

 finally reaches a height at which its impulsive 

 force meets with a counterpoise, and between the 

 two the balloon finds its level. 



The wind's speed may be nothing, or it may ex- 

 ceed seventy miles an hour. A dead calm often 

 leaves the balloon in queer places, from which 

 extrication is not difficult, for a boy may walk 

 away with it, or a skiff can carry it to the shore. 

 It is different in high winds ; then we have a 

 monster to handle, which at times can only be 

 conquered by ripping "open its gas - expanded 

 sides. Thunder-storms are to be avoided, and 

 the aeronaut must be wary, or he may be drawn 

 into them very unexpectedly. Do not run high, 

 but rather keep as low as possible. Ordinary 

 rain-storms are unpleasant, for the water courses 

 down the sides of the silken globe, falling in 

 streams from its neck into the car ; yet the moist- 



ON THE OCEAN WAVE. 



ure does not affect the voyage in any great de- 

 gree. But beware of snow clouds, for the little 

 crystals may gather in such quantity on the 

 broad roof above your head that a sudden de- 

 scent will bring you to the ground in spit* of 

 all your efforts. 



