You will tell me, perhaps, there is a sort of regularity about my preliminary work that does not please the eye. You would like, perhaps, to make a graceful balloon like [Fig. 3].

Better not. Do you not see what would happen when you came to set light to the fuel suspended under the mouth of the balloon? The flame would almost certainly strike against the paper of the narrow neck, and presently the whole balloon would be in a blaze.

Having cut out your gussets, the next thing is to join them. First as to cement. Use thin paste or gum water, which you please, and employ a camel-hair, or better, a sable-brush, to spread it. Half an inch lap is quite enough; and when the necessary paper junction has been made, I like to dry my work at once by means of a laundress’s smoothing iron. Taking this precaution, you will have no sticking at spots where sticking ought not to be.

A final word now about the best way of bringing the edges of your gussets together. The line diagram here given will make all comprehensible: a and b represent, we will say, two gussets.

Fig. 5.
Fig. 3.
Fig. 4.Fig. 6.

The edge of a is alone to be gummed or pasted to about half an inch wide; the corresponding edge of b is then to be bent down upon the cemented edge of a, and dried at once with the laundress’s hot iron; not laid naked upon the paper, but having a thickness of flannel interposed. Proceeding thus all round, you will at last finish your balloon all but the crown pieces and mouth stiffener. For a balloon of the dimensions recommended, I would advise you to paste on a crown piece of about a foot diameter. Don’t make it of tissue-paper, but of soft whitey brown paper, and in the middle of it paste a loop of calico, something similar to the loop of a saucepan lid. The utility of this will be found out when you come to let off your balloon.

As a mouth stiffener I prefer a circle of thick iron or brass wire to anything else. About three inches from the balloon-mouth had better be strengthened by a layer of calico, which being gashed or scalloped ([Fig. 5]), pasted and turned over the wire hoop, makes all firm. As to dimensions of mouth, I consider a circle of eighteen inches’ diameter quite big enough, and boys will please remember that three times and about one-seventh of a diameter makes the circumference of a circle.

Having made your balloon, the next thing to do, as it would seem, is to let it off.

Not exactly. You expect your balloon to lift a weight—fireworks probably—which I will describe how to manage by-and-by. It will be necessary, then, to learn by experiment how much weight it will carry; otherwise, when the time of letting off arrives, you may fail altogether, and be much disappointed.

The weight-carrying experiment must be performed in a room, to avoid air-currents, and, as a preliminary, some sort of car must be attached to the balloon for the purpose of holding the weights. The car may be of various shapes, but as good a shape as any is this:—