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to arrange themselves in one direction, like the grain in wood. For halfpenny wheels, divide the sheet into two pieces, each 10 by 30; then cut each of these into 12, each 10 by 21. For a former, have a straight piece of iron, or steel, wire, of an inch thick, and 24 inches long. One end of this must have a basil, or sloping enlargement upon it, which is thus made. Take a piece of double-crown 4 inches square; lay it straight before you, and cut it diagonally, from the right top corner to the left bottom corner; remove the left half; paste the right; lay the wire upon it, so that the rectangular corner is 5 inches from the right end of the wire; roll it up, and press it smooth; the sloping edge will now form a spiral, commencing at 9 inches from the right end of the wire, and being enlarged at 5 inches from the end. Paste a thin strip of paper over the whole, to protect the spiral edges. It will now be something of the shape of fig. 27, only turned the reverse way. The 5 inches at the end are for a handle. To roll the pinwheel pipes, lay the strips of paper evenly upon each other, and work them back with the thumbnail, as before. Paste the

edges; lay half-a-quire of double-crown, or of blotting-paper, flat upon the table, to roll on. Place one of the strips of pasted paper upon it; lay the wire upon it, the basil end being towards the right hand; the wire is to be laid, not quite parallel with the near edge of the paper, but slightly sloping, about an inch and a quarter distant from it on the left, and not quite an inch on the right, or basil end. So much of the basil must lie on the paper as will make the mouth of the pipe large enough for the nozzle of the funnel to enter half-an-inch. The basil, of course,

gathers up the paper more quickly than the wire, and brings the edge straight, on the completion of the pipe. Now to roll, bend the paper over the left end of the wire, press it in with the fingers, and begin immediately to move it forward; at the same time draw the fingers of the right hand rapidly along, pressing in the paper, and rolling forward, keeping the right, or basil, end of the wire tight, and slightly pulled towards you: the paper round the left end of the wire will have thus become rolled half round the circumference of the wire, before the basil end has

begun. There is very great difficulty, at first, in rolling so long a pipe as 17 inches; it is advisable to begin with the halfpenny pipes, which are much shorter; the same wireformer will serve for both. If you cannot succeed, get a person to help you; sixteen fingers can manage the matter easily; but it is best to master the difficulty yourself. Have a funnel as nearly the size and shape of fig. 66 as possible. It is best with a lid soldered. on the top, with a circular hole in the middle, about the size of a shilling, to prevent the composition from getting spilt. A slightly tapering neck is also to be soldered on at the bottom. Take especial care that the mouth of the funnel dips into the neck, and not have the neck sticking up in the funnel. The joint inside must be perfectly smooth. A charging wire will now be required; this should be a square steel wire, as large as the neck of the funnel will admit, to move easily up and down; let it also have a piece of lead at the end, to give it weight. Take a piece of brass tube, about of an inch diameter, and an inch long. Hold the wire in it, with a piece of flannel, or woollen cloth, and pour

in melted lead. To charge To charge the cases, first bend a quarter of an inch of the small end of the pipe, over the edge of a knife, into a hook, to prevent the composition running out; insert the nozzle of the funnel in the enlarged end; hold the part of the pipe now round it, with the thumb and forefinger of the left hand, slip the wire, through the funnel, down to the bottom of the pipe, which must rest, for a moment, on the table; pour in the composition, jolt the wire up and down; lift the pipe from the table, keep jolting the wire, at the same time turning it round, and let the pipe swing slightly to and fro, till filled. A guide-mark must be filed round the wire, as for squibs, at such a distance as that, when it is level with the top of the funnel, the bottom may protrude about of an inch. When a number of pipes are charged, close the large, or basilled, end, which is the one to be lit, by means of a piece of whipcord, or thin twine, wound round it, as directed in figs. 63 and 64. Soak a towel in water; wring it as dry as possible; spread it out flat; lay the pipes in a row, side by side, upon it, like rushes in a chair bottom; roll them up in it,

and leave them for 10 or 15 minutes.

Then

wind them upon the usual circular blocks, and fasten the end with sealing-wax. Be careful

that the wax is not in a flame at the moment of touching the case; if necessary, blow it out. Accidents will arise, both from the wax and from the candle, if care is not used. Measure, with a tape, round the wheel, now wound; suppose 4 inches ; cut a piece of blue double-crown, 4 inches broad, and any length: cut this into strips about of an inch broad, and 4 inches long; paste a slate all over; lay these strips, 7 or 8 of them, side by side, flat upon it; paste their upper surface; lay one across each pinwheel, and bend it over to make the ends meet in the centre on the other side. If you wish the pinwheel to be of double or triple size, after you have charged one pipe, paste the small end of a second pipe, outside, and stick it in the other. Let it dry; then charge the additional pipe. Observe, the pipes must not lie too long in the towel; if the nitre gets dissolved, it soaks into the paper, which becomes, virtually, touchpaper, and one pipe ignites the other. The wire formers must not be allowed to get rusty;

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