448
PYROTECHNY.
paper thicker in one place than another ; anti also to know whenthe shell is of a proper thickness. Balloons must always be madeto go easy into the mortars.
Cases for Illumination-Portfires. —These must be made verythin of paper, and rolled on formers from 2 to 5-8ths of an inchdiameter, and from two to six inches long; they are pinchedclose at one end, and left open at the other. When yon fill them,put in but a little composition at a time, and ram it in lightly, soas not to break the case : three or four rounds of paper, with thelast round pasted, will be strong enough for these cases.
Cases and Moulds for Common Port-fires. —Common port-firesare intended purposely to fire the works, their fire being very-slow, and the heat of the flame so intense, that, il applied to rockets,leaders, &c. it will fire them immediately. Port-lires may bemade of any length, but are seldom made more than 21 incheslong: the interior diameter of port-fire-moulds should be 10-l6thsof an inch, and the diameter of the former half an inch. The casemust be rolled wet with paste, and one end pinched, or foldeddown. The moulds should be made of brass, and to take in twopieces lengthwise; when the case is in the two sides, they are heldtogether by brass-rings, or hoops, which are made to lit over theoutside. The bore of the mould must be made cpiite through, so jthat there will be no occasion for a foot. Those port-fires, when Iused, are held in copper-sockets, fixed on the end of a long slick : jthese sockets are made like port-crayons, only with a screw insteadof a ring.
Dimensions and Poise of Rocket-sticks.
Weightof therocket.
Lengthof thestick.
Thick-ness attop.
Breadthat top.
Square jat J
bottom.
Poise from,the point ofthe cone.
ibs. oz.
ft.
in.
Indies.
Inches.
Inches.
feet.
inch
6 0
14
0
1,5
1,85
0,75
4
1,5
4 0
12
10
1,25
1,40
0,(525
3
9,
2 0
9
4
1,125
1,
0,525
2
9,
1 0
8
2
0,725
0,80
0,375
2
1,
8
6
ti
0,5
0,70
0,25
i
10,5
4
5
3
0,3750
0,55
0,35
i
8,5
2
4
1
0,3
0,45
0,15
i
3,
1
3
6
0,25
0.35
0,10
0
1 1
1
2
4
0,125
0,20
0,0(5
0
8
r
%
1
104
0,1
0,15
0,
0
5,5
To Load Air-balloons, with the Number of Stars, Ser-pents, Snakes, Rain-falls, &c. in Shells or eachNature.
Mortars to throw Aigrettes, dye.—When you fill your shells,you must first put in your serpents, rains, stars. &c. or whateverthey are composed of, then the blowing powder; but the shellsmust not be cpiite filled. All those things must be put in at thefuze-hole ; but maroons being too large to go in at the fuze-hole,must be put in before the inside shall be joined. When the shellsare loaded, glue and drive in the fuzes very tight. For a coehorn-balloon, let the diameter of the fuze-hole be £ths of an inch; fora royal balloon, which is near 5| inches in diameter, make thefuze-hole 1 inch. £ diameter; for an 8-inch balloon, l-incli *ths;and fora 10-inch balloon, 1 inch ilths.
7o make balloon fuzes. —Fuzes for air-balloons are sometimesturned out of dry beech, with a cup at top to hold the quick-match ; but if made with pasted paper, they will do as well. Thediameter of the former for fuzes for coehorii-halloons must be | aninch ; for a royal fuze, -jttlis of an inch: for an 8-inch fuze, Rhs ofan inch: and fora 10-inch fuse it I is of an inch. Ilaving*rolledyour cases, pinch and tie them almost close at one end ; then drivethem down, and let them dry. Before you begin to fill them,mark on the outside of the case the length of the charge re-quired, allowing for the thickness of the bottom ; and when youhave rammed in the composition, take two pieces of quick-matchabout six inches long, and lay one end of each on the charge, andthen a little meal-powder, which ram down hard ; the loose ends
1
I of the match double up into the lop of the fuze, and cover it witha paper-cap to keep it dry. When you put the shells in themortars, uncap the fuses, and pull out the loose ends ot the match,and let them hang on the sides oi the balloons.
Tourbillons . — Having filled soim cases with about 1| diameter,drive in a ladleful of clay, then pinch their ends close, and drivethem down with a mallet. When done, find the centre of thegravity of each case, w-here you mint nail and tie a slick, whichshould be half an inch broad at the middle, and run a little narrowto the ends: these sticks must have their ends turned upwards, sothat the cases may turn horizontally on their centres. At the op-posite sides of the cases, at each end, bore a hole close to the claywith a gimlet, the size of the neck of a common case of the samenature; from these holes draw a line round the case, and at theunder pari of the case bore a hole wilh the same gimlet, within oue-half diameter of each line towards die centre ; then from one holeto the other draw a right line. When you lire tourbillons, lay themon a smooth table, with their sticks downwards, and bum the leaderthrough the middle with a port-lire. They should spin three orfour seconds on the table beiore they rise, which is about the timethe composition will be burning from the side-holes to those atbottom.
Aquatic Firf.-Works.
Pire-lTorks tha' sport in the water are much esteemed by mostadmirers of Bvroteehnv, particularly water-rockets; and as theyseem of a very extraordinary nature to those who are unacquaint-ed wilh this art, they merit a particular explanation.
Hater-Rockets mav he made Irom 4oz. to 2ll>. If larger,they are too heavv ; so that it will be diffu nil to make them keepabove water without a cork-float, which must be tied to the neckof the ease ; but the rockets will not dive so well with as withoutfloats. Cases for these are made ill the same manner and propor-tion as sky-rockets, only a little thicker ol paper. \\ lien yon tillthose which are drove solid, put in first one ladleful of slow lire,then two of the proper charge, and on that one or two ladles ofsinking charge, then the proper charge, then the sinking chargeagain, and so on, till you have idled the case within threediameters ; then drive on the composition one ladleful of clay ;through which make a small hole to the charge ; then till the rase,within half a diameter, with corn-powder, on which turn downtwo or three rounds of the case in the inside ; then pinch and tiethe end very tight; having filled your rockets (according to theabove directions) dip their ends in melted rosin or sealing-wax, orelse secure them well with grease. AN'lien you fire those rocket-',throw in six or eight at a time; but, if you would have them allsink, or swim, at the same time, you must drive them with an equalquantity of composition, and lire them altogether.
To make Pipes of Communication, to he used under Hater .—Pipes for this purpose, must he a little thiiker of paper than thosefor land. Having rolled a sufficient number of pipes, and kepttill dry, wash them over with drying oil, and set them to drv ;but when yon oil them, leave about one inch and a half at eachend dry, lor joints: if they were oiled all over, when you cometo join them, the paste would not stick where the paper is greasy :after the leaders are joined, and the paste dry, oil the joints.These pipes will lie many hours under water, without receivingany damage.
'Horizontal H'hcets for the ITaicr. —First get a large woodenhowl without a handle ; then have an octagon-wheel made of aflat board eighteen inches diameter, so that the length of eachside will be near seven inches : in all the sides cut a groove forthe ease to lie in. This wheel being made, nail it on the top ofthe bowl : then take four-eight oz. eases, tilled with a propercharge, each about six inches in length. Now, to clothe thewheel with these cases, get some whitish-brown paper, anil cut itinto slips four or live inches broad and seven or eight long: thoseslips being pasted all over on one side, take one of the eases aiidroll one of the slips of paper about one inch and a half on itsend, so that there will remain about two inches and a half ofthe paper hollow from the end of the case : this case tie on oneof the sides of the wheel, near the corners of which must beholes bored, through which you put the packthread to tie tin-eas es: having tied on the first case at the neck and end, put alittle meal-powder in the hollow paper ; then paste a slip of paper
on