The parachute I shall describe for your fire-balloons is a more simple affair, and is made as follows:—Provide yourself with two sheets of soft whitey-brown paper, some twine, and some paste. Lay one sheet flat on a table, and then extend diagonally from corner to corner two lengths of twine which must project at least six inches beyond each corner. It may be wanted to project even more, but in that case each cord terminal may be easily lengthened to the desired extent by tying the necessary additional length of twine to it. Now spread a film of thin paste evenly by a brush over the sheet of paper and twine, and then close the second sheet of paper in exact correspondence with the first, as represented in the diagram.
Be particular, in sticking the two sheets of paper together, to avoid formation of air bubbles. This can only be done by making the pasting together successive and not instantaneous—that is to say, do not lay the second sheet of paper flat down upon the first sheet all at once, but having begun to effect the attachment at any one edge, follow on deliberately to the opposite edge, patting the two sheets well together with a soft pocket-handkerchief.
The way of using such a parachute hardly needs explanation. The projecting lengths of twine having been brought together, are attached to a car, and the whole suspended to your balloon, from which you intend that it shall separate and begin to fall, on your balloon attaining the desired elevation. This detachment can easily be effected by Bickford’s fuse. Here, whilst I think of it, never attempt to ignite a Bickford fuse with anything else than the flame of a port-fire or a blue-light. The chief beauty of any firework device consists in working to exact time. A Bickford fuse cannot readily be set on fire with a match-flame. You may crack many lucifers over the job without succeeding; your balloon, that ought to be off on its travels, all the time kept waiting.
Fig. 16.
What will you put in the car? I shall leave this pretty much to your own taste. Some sort of weight there must be to pull the parachute down. I have heard of some boys who for ornament peopled the car with little figures of comical men, cut out of cardboard. I don’t see myself the sense of it. Fire-balloons are usually let off at night, when the little caricatures would almost need a spyglass to see them even before the balloon set out on its explorations. Balloons once off nobody could see the little men at all. However, do as you like, boys; [here] are two notions of such caricature men.
Attention! The point up to which you and I have been working is near. We are going to let off the balloon. When we were making our chamber trial, you will remember we used methylated spirit for fuel, absorbing it by a sponge. You may use the same sort of fuel now if you please, but as for myself I much prefer the good flare of cotton lamp-wick saturated with tallow, and sprinkled with either benzoline or turpentine, so that it may burst into flame without delay at the first touch of other flame. Not only does tallow burn with a far brighter light than spirits of wine, but the flame is more lasting. However, boys, I say again—do as you like. So now farewell to fire-balloons. I will now proceed to tell you how to make and fill so-called air-balloons, though gas-balloons would be a name more fitting. They are not of themselves illuminative, as fire-balloons are, but they will take up any fireworks you please, according to their weight-carrying capabilities.
