not be tied in a knot, but fastened with two 
or three hitches. 
Having thus pinched and tied the case so 
as not to give way, put it into the mould 
without its foot, and with a mallet drive the 
former hard on the end piece, which will force 
the neck close and smooth. This done, cut 
the case to its proper length, allowing from 
the neck to the edge of the mouth half a dia- 
meter, which is equal to the height of the 
nipple; then take out the former, and drive 
the case over the piercer with the long ram- 
mer, and the vent will be of a proper size. 
Wheel-cases must be driven on a nipple with 
| a point to close the neck, and make tae vent 
[ of the size required ; which, in most cases, 
is generally one-quarter of their interior dia- 
meter. As it is very often difficult, when the 
cases are rolled, to draw the roller out, you 
may make a hole through the handle, and put 
in it a small iron pin, by which you may 
easily turn the former round and pull it out. 
Cases are commonly rolled wet, for wheels 
and iixed pieces ; and when they are re- 
quired to contain a great length of charge, 
tiie method of making those cases is thus : 
I your paper must be cut as usual, only the last 
sheet must not be cut with a slope; having 
Your paper ready, paste each sheet on one 
j side ; then fold clown the lirst sheet as before 
| directed; but be careful that the paste does 
not touch the upper part of the fold, for if the 
roller is wetted, it will tear the paper in draw- 
ing it out. In pasting the last sheet, observe 
'not to wet the last turn or two in that part 
where it is to be pinched; for if that part is 
damp, the pinching-cord will stick to it, and 
tear the paper; therefore, when you choak 
those cases, roll a bit of dry paper once round 
the case before you put on the pinching-cord ; 
but this bit of paper must be taken off after 
the case is choaked. The rolling-board, and 
ail other methods, according to the former 
directions for the rolling and pinching of cases, 
must be used to these as well as all other 
' cases. 
43. To make tourbilliil-cases . This sort 
of cases are generally made about eight dia- 
meters long; but if very large, seven will be 
sufficient. Tourbillons will answer very well 
from 4 oz. to 2 lb. but when larger there is no 
certainty. The cases are best rolled wet with 
paste, and the last sheet must have a straight 
edge, so that the case may be all of a thick- 
ness. When you have rolled your eases after 
the manner of wheel-cases, pinch them atone 
end quite close ; then with the rammer drive 
the ends down flat, and afterwards ram in 
about one-third of a diameter of dried clay. 
The diameter of the former for these cases 
must be the same as for sky-rockets. 
44. Balloon-cases, or paper shells. First, 
you must have an oval former turned of 
smooth wood; then paste a quantity of brown 
or cartridge paper, and let it lie till the paste 
has quite soaked through : this done, rub the 
former with soap or grease, to prevent the 
paper from sticking to it; then lay the paper 
on in small slips, till you have made it one- 
third of the thickness of the shell intended. 
Having thus clone, set it to dry, and when 
dry, cut it round the middle, and the two 
halves will easily come off; but observe,’ 
when you cut, to leave about one inch not cut, 
which will make the halves join much better 
than if quite separated. When you have 
some ready to join, place the halves even to- 
5 
FYHOTECHNY. 
1 gefcher, paste a slip of paper round the open- 
i mg to hold them together, and let that dry ; 
I then lay on paper all over as- before, every 
where equal, excepting that end which goes 
downwards in the mortar, which may be a 
little thicker than the rest ; for that part 
which receives the blow frotn the powder in 
the chamber of the mortar consequently re- 
quires the greatest strength. When the shell 
is thoroughly dry, burn a round vent at top, 
with an iron large enough for the fuze : this 
method will do for balloons from 4 inches 
2-5 ths, to 8 inches diameter; but if they are 
larger, or required to be thrown a great height, 
let the lirst shell be turned of elm, instead of 
being made of paper. For a balloon of 4 
inches 2-5ths, let the former be 3 inches l-8th 
diameter, and 5^ inches long. For a balloon 
of 5^ inches, the diameter ot the former must 
be 4 inches, and 8 inches long. For a balloon 
of 8 inches, let the diameter of the former be 
5 inches and 15-1 6ths, and 11 inches 7-8 ths 
long. Fora 10-inch balloon, let the former 
be 7 inches 3-1 6ths diameter, and 144 inches 
long. The thickness of a shell for a balloon 
of 4 inches 2-5ths must be half an inch. For 
a balloon of 5-j; inches, let the thickness or the 
paper be 5-8ths of an inch; for an S-inch 
balloon, 7-8ths of an inch ; and for a 10-inch 
balloon, let the shell be 1 inch l-8th thick. 
Shells that are designed for stars only, may be 
made quite round, and the thinner they are 
at the opening, the better; lor ii they are too 
strong, the stars are apt to break at the burst- 
ing of the shell. When you are making the 
shell, make use of a pair of calibres, or a 
round gage, so that you may not lay the 
paper thicker in one place than another ; and 
also to know when the shell is ot a proper 
thickness. Balloons must always be made to 
go easy into the mortars. 
Cases for illumination port-fires. These 
must be made very thin of paper, and rolled 
on formers from 2 to 5-8ths of an inch dia- 
meter, and from 2 to 6 inches long: they are 
pinched close at one end, and left open at the 
other. When you till them, put in but a 
little composition at a time, and ram it in 
lightly, so as not to break the case: three or 
four rounds of paper, with the last round 
pasted, will be strong enough for these cases. 
Cases and moulds for common portfires. 
Common port-iires are intended purposely 
to fire the works, their fire being very slow, 
and the heat of the flame so intense, that, if 
applied to rockets, leaders, &c. it will fire 
them immediately. Port-fires may be made 
of anv length, but are seldom made more 
than 21 inches long: the interior diameter of 
port-fire moulds should be 10-l6ths of an 
inch, and the diameter of the former half an 
inch. The cases must be rolled wet with 
paste, and one end pinched, or folded clown, 
l he moulds should be made of brass, and to 
take in two pieces lengthwise ; when the case 
is in the two sides, they are held together by 
brass rings, or hoops, which are made to fit 
over the outside. The bore of the mould 
must not be made quite through, so that there 
will be no occasion for a foot. r l hose port- 
fires, when used, are held in copper sockets, 
fixed on the end of a long stick : these sockets 
are made like port-crayons, only with a screw 
instead of a ring. 
45. Of mixing the compositions . The per- 
formance of the principal part of fire-works 
3X2 
531 
depends much on the compositions being well 
mixed ; therefore great cure must be taken 
in this part of the work, particularly for the 
composition for sky-rockets. When you have 
four or live pounds oi ingredients to mix, 
which is a sufficient quantity at a time, first 
put the different ingredients together, then 
work them about with your hands till you 
think they are pretty well incorporated; after 
which put them into a lawn sieve with a re- 
ceiver and top to it ; and if, after it is sifted, 
any remains that will not pass through the 
sieve, grind it again till fine enough, and il it 
is twice sifted it will not be amiss; but the 
compositions for wheels and common works 
are not so material, nor need be so fine. But 
in all fixed works, from which the fire is to 
play regularly, the ingredients must be very 
line, and great care taken in mixing them 
well together; and observe, that in all com- 
positions wherein are steel or iron filings, the 
hands must not touch: nor will any works 
which have iron or steel in their charge keep 
long in clamp weather, unless properly pre- 
pared, according to the following directions: 
46. To preserve steel or iron flings. Melt 
in a glazed earthen pan some brimstone over 
a slow fire, and when melted throw in some 
filings, which keep stirring about till they are 
covered with brimstone: this you must do 
while it is on the fire ; then take it off, and 
stir it very quick till cold, when you must 
roll it on a" board with a wooden roller till you 
have broken it as fine as corn-powder ; after 
which sift from it as much of the brimstone as 
you can. There is another method of pre- 
paring filings, so as to keep two or three 
months in winter : this may be done by rub- 
bing them between the strongest sort of brown 
paper, which before lias been moistened with 
linseed oil. 
To load air-balloons, zd tilth e number of stars, 
serpents, snakes, rain-jails, fyc. in shells 
of each nature. 
48. Mortars to throw aigrettes, 3rc. When 
you fill your shells, you must first put in the 
serpents, rains, stars, &c. or whatever they 
are composed of, then the blowing powder ; 
but the shells must not be quite filled. All 
