OF THE MANNER OF FIXING AND ARRANGING FIRE-WORKS IN GENERAL FOR
EXHIBITION.
Having already treated of the formation of various kinds of
fire-works, we come now to consider their arrangement in fixed and
moveable pieces.
It is obvious, that the order of arrangement, the manner of disposing
the work, or establishing pieces for exhibition, may be greatly
varied according to taste and fancy. The great variety of fixed and
moveable pieces, consisting of suns, moons, stars, &c. which may be
either made permanent, or to revolve on, or round a centre; or of
wheels, double, single, or treble, either moving round other wheels,
or by themselves in a vertical or horizontal order, together with
the arrangement of fire-pots, and coloured lights, the management
of rockets, the formation of aerial stars, serpents, tourbillons,
&c. and the imitation of cascades, girandoles, and water-falls, all
depend on the taste and fancy of the artist.
It is our intention, therefore, in the different sections of this
chapter, to give the order and arrangement of pieces, as adopted in
Europe, and particularly in France; so that the manner of fixing any
one piece, or combination of pieces, to produce effects of different
kinds, may be seen at one view. The moveable pieces are generally
made of wheel-work, the wheel always turning upon an axle, which may
pass entirely through and be kept on by a nut or pin. They should
revolve without much friction, and, for this reason, the spindle
should be of metal, and oiled or greased. Black lead, along with
tallow, will diminish the friction very considerably. As to the
formation of the wheel, whether it be solid, or formed of spokes
and a band or hoop, or made with several concentric bands, placed
at given distances apart, &c. the observations on this head will be
found under the respective articles, and, generally, on all other
pieces for exhibition.
We purpose, in a subsequent chapter, to notice particularly
the works, made in and on water, usually denominated _aquatic
fire-works_; as their arrangement, in many respects, differs from
those on the land. Aquatic works furnish a variety, both in character
and effect, and, therefore, are calculated to produce, in conjunction
with land works, a brilliant spectacle. Of this, we have an instance,
mentioned in the introduction to this part of our work, in the
splendid exhibition at the _Pont Neuf_ in Paris.
_Sec. I. Of the Composition of Wheel-Cases, standing and fixed._
It may not be improper, before noticing the arrangement of
wheel-cases, to give in this place the compositions, which are
used for charging them, reserving, however, the notice of some
preparations, when we treat of such works, in which they are
particularly employed.
_Wheel-cases from two ounces to four pounds._
1. Meal-powder, 2 lbs.
Saltpetre, 4 oz.
Iron-filings, 7 --
2. Meal-powder, 2 lbs.
Saltpetre, 12 oz.
Sulphur, 4 --
Steel-dust, 3 --
3. Meal-powder, 4 lbs.
Saltpetre, 1 --
Sulphur, 8 oz.
Charcoal, 4½ --
4. Meal-powder, 8 oz.
Saltpetre, 4 --
Sawdust, 1½ --
Sea-coal, ¾ --
5. Meal powder, 1 lb. 4 oz.
Sulphur, 4 -- 10 dr.
Saltpetre, 8 --
Glass-dust, 2½ --
6. Meal-powder, 12 oz.
Charcoal, 1 --
Sawdust, ½ --
7. Saltpetre, 1 lb. 9 oz.
Sulphur, 4 --
Charcoal, 4½ --
8. Meal-powder, 2 lbs.
Saltpetre, 1 --
Sulphur, ½ --
Sea-coal, 2 oz.
9. Saltpetre, 2 lbs.
Sulphur, 1 --
Meal-powder, 4 --
Glass-dust, 4 oz.
10. Meal-powder, 1 lb.
Saltpetre, 2 oz.
Steel-dust, 3½ --
11. Meal-powder, 2 lbs.
Steel-dust 2½ oz.
Beat iron, 2½ --
12. Saltpetre, 2 lbs. 13 oz.
Sulphur 8 --
Charcoal, 4 --
_Slow fire for wheels._
1. Saltpetre, 4 oz.
Sulphur, 2 --
Meal-powder, 1½ --
2. Saltpetre, 4 oz.
Sulphur, 1 --
Antimony, 1 -- 6 dr.
3. Saltpetre 4½ oz.
Sulphur, 1 --
Meal-powder, 1½ --
_Dead fire for wheels._
1. Saltpetre, 1¼ oz.
Sulphur, ¼ --
Lapis calaminaris, (prepared calamine,) ¼ --
Antimony, 2 dr.
_Standing, or fixed cases._
1. Meal-powder, 4 lbs.
Saltpetre, 2 lbs.
Sulphur and charcoal, (together,) 1 --
2. Meal-powder, 2 lbs.
Saltpetre, 1 --
Steel-dust, 8 oz.
3. Meal-powder, 1 lb. 4 oz.
Charcoal, 4 oz.
4. Meal-powder, 1 lb.
Steel-dust, 4 oz.
5. Meal-powder, 2½ lbs.
Sulphur, 4 oz.
Seacoal, 6 --
6. Meal-powder, 3 lbs.
Charcoal, 5 oz.
Sawdust, 1½ --
_Sun cases._
1. Meal-powder, 8½ lbs.
Saltpetre, 1 -- 2 oz.
Steel-dust, 2 -- 10 --
Sulphur, 4 --
2. Meal-powder, 3 lbs.
Saltpetre, 6 oz.
Steel-dust, 7½ --
_Crowns or globes._
1. Saltpetre, 6 oz.
Sulphur, 2 lbs.
Antimony, 4 oz.
Camphor, 2 --
This view of the compositions used in fixed and turning pieces,
exhibits the various compounds which _have been_ employed, and,
therefore, may be relied upon. Notwithstanding they are considered
the standard formulæ; yet we must observe, that in some, particularly
in the turning sun, with variations, changes are required, in order
to produce a variety in the effect. This is accomplished, by making,
in the first place, a particular composition, and mixing a given
quantity of it with meal-powder, which forms the second change.
Of this second composition, combined in a given proportion, with
meal-powder, we form a third change; and, in like manner, we employ
the third along with more powder, to form a fourth, and the fourth to
form a fifth. The particular manner of making these changes will be
described in a future section.
_Sec. II. Of Single, Vertical, Horizontal, Spiral, and other wheels._
Of the different kinds of _vertical wheels_, we may mention, that
some have their fells of a circular form, others, in the form of
a hexagon, octagon, or of a figure of a greater number of sides,
according to the length of the cases designed for the wheels. The
spokes being fixed in the nave, nail slips of tin, with their edges
turned up, so as to form grooves for the cases to lie in, from the
end of one spoke to another. Then tie the cases in the grooves head
to tail, in the same manner as those on the horizontal water-wheel;
so that the cases successively taking fire from one to another,
will keep the wheel in an equal rotation. Two of these wheels are
very often fired together, one on each side of a building, and both
lighted at the same time, and all the cases filled alike to make
them keep time together. This may be accomplished in the following
manner. In all the cases of both wheels, except the first, and on
each wheel, drive two or three ladles full of slow fire, in any part
of the cases, but be careful to ram the same quantity in each case;
and in the end of one of the cases on each wheel, one ladle full
of dead-fire composition, which must be very lightly driven. Many
charges of fire may be made by the same method.
The hole in the nave of the wheel may be lined with brass, and made
to turn on a smooth iron spindle. On the end of this spindle, let
there be a nut to screw off and on. When we have placed the wheel on
the spindle, screw on the nut, which will keep the wheel from flying
off. Let the mouth of the first case be a little raised.
Vertical wheels are made from ten inches, to three feet in diameter,
and the size of the cases must vary accordingly. Four-ounce cases
will be sufficient for wheels of fourteen or sixteen inches in
diameter, which is the proportion generally used. The best wood for
wheels of all kinds, is the light and dry beech.
_Horizontal wheels_ are more perfect, when their fells are made
circular. In the middle of the top of the nave must be a pintle,
turned out of the same piece as the nave, two inches long, and equal
in diameter to the bore of one of the cases of the wheel. There must
be a hole bored up the centre of the nave, within half an inch of
the top of the pintle. Nail at the end of each spoke, of which there
should be six or eight, a piece of wood with a groove, cut in it to
receive the case. Fix these pieces in such a manner, that half the
cases may incline upwards, and half downwards, and that, when they
are tied on, their heads and tails, or extremities, may come very
near together. From the tail of one case to the mouth of the other,
carry a leader, which is necessary to be secured with pasted paper.
Besides these pipes, a little meal-powder must be placed in the
inside of the pasted paper, to blow off the pipe, that there may be
no obstruction to the fire from the cases. By means of these pipes,
the cases will successively take fire, burning one upwards, and the
other downwards. On the pintle, fix a case of the same sort as those
on the wheel. This case must be fired by a leader from the mouth of
the last case on the wheel, which case must play downwards. Instead
of a common case in the middle, we may put a case of Chinese fire,
sufficiently long to burn a given time, or as long as two or three
cases on the wheel.
Horizontal wheels are often fired two at a time, and made to keep
time, like vertical wheels, only they are prepared without any
slow or dead-fire. Ten or twelve inches will be sufficient for the
diameter of wheels with six spokes.
With respect to _spiral wheels_, we may remark, that they are only
double horizontal wheels, made in the following manner: The nave
must be thicker than that of the single sort; and, instead of the
pintle at top, a hole is usually made for the case to be fixed in.
There are two sets of spokes, one set put near the top of the nave,
and the other, near the bottom. At the end of each spoke, cut a
groove, in which the cases are to be tied, there being no fell. The
spokes should not be more than three and a half inches long from the
nave, so that the wheel may not be more than eight or nine inches
in diameter. The cases are placed in such a manner, that those at
top play down, and those at the bottom play up; but let the third or
fourth case burn horizontally. The case in the middle may begin with
any of the others. Six spokes will be sufficient for each set; so
that the wheel may consist of twelve cases, besides that on the top;
the cases six inches each.
_Plural wheels_ are different from the former. They are made to turn
horizontally, and consist of three sets of spokes, placed six at top,
six at bottom, and four in the middle, which must be a little shorter
than the rest. Let the diameter of the wheel be ten inches. The cases
must be tied on the ends of the spokes, in grooves, cut on purpose,
or in pieces of wood, nailed on the ends of the spokes, with grooves
cut in them as usual. In clothing these wheels, make the upper set
of cases play obliquely downwards, the bottom set obliquely upwards,
and the middle set, horizontally. In placing the leaders, we must
so arrange them, as that the case may turn thus: namely, first up,
then down, then horizontally, and so on with the rest. But another
change may be made, by driving in the end of the eighth case two or
three ladles full of slow fire, to burn till the wheel has stopt its
course. Then let the other cases be fixed the contrary way, which
will make the wheel run back again. For the case at top, we may put
a small gerbe, and the cases on the spokes may be short, and filled
with the strong brilliant charge.
For forming the _illuminated spiral wheel_, we must proceed thus:
First have a circular horizontal wheel, made two feet in diameter,
with a hole quite through the nave; then take three thin pieces of
light board, three feet long each, and three-fourths of an inch
broad. One end of each of these pieces, nail to the fell of the
wheel, at an equal distance from one another; and the other end, nail
to a block with a hole in its bottom, which must be perpendicular
to that in the block of the wheel, but not so large. Plane a hoop
down very thin and flat, and nail one end of it to the end of the
wheel, and wind it round three sticks in a spiral line, from the
wheel to the block at top. On the top of this block, fix a case of
Chinese fire. On the wheel may be placed any number of cases, which
must incline downwards, and burn two at a time. If the wheel should
consist of ten cases, we may let the illuminations and Chinese fire
begin with the second cases. The spindle for this wheel must be a
little longer than the cone, and made very smooth at top, on which
the upper block is to turn, and the whole weight of the wheel to rest.
For making the _double spiral wheel_, the block, or nave, must be as
long as the height of the worms, or spiral lines; but must be very
thin, and as light as possible. In this block fix several spokes,
which must diminish in length from the wheel to the top, so as not to
exceed the surface of a cone of the same height. To the ends of these
spokes nail the worms, which must cross each other, several times.
These worms clothe with the same illuminations as those on the
single wheels, but the horizontal wheel may be clothed according to
fancy. At the top of the worm, place a case of slow fire, or an amber
light.
_Balloon wheels_ turn horizontally. They are usually made two feet
in diameter without any spokes, and very strong, with any number
of sides. On the top of the wheel, range and fix in pots of three
inches in diameter, and seven inches high each, as many as there
are cases on the wheel. Near the bottom of each pot, make a small
vent; and into each of these vents, carry a leader from the tail of
each case. Some of the pots may be charged with stars and some with
serpents, crackers, &c. As the wheels turn, the pots will be fired in
succession, and throw into the air a great variety of fires.
_Fruiloni wheels_ are made with a nave, nine inches long, and three
inches in diameter. Near the bottom of this nave, fix eight spokes
with a hole in the end of each, sufficiently large to receive a two
or four-ounce case. Each of these spokes may be fourteen inches long
from the block. Near the top of this block, fix three more of the
same spokes, exactly over the others, but not so long by two inches.
As this wheel is to run horizontally, all the cases in the spokes,
must play obliquely upwards, and all those in the spokes at bottom,
obliquely downwards. This being accomplished, have a small horizontal
wheel, made with eight spokes, each five inches long from the block.
On the top of this wheel, place a case of brilliant fire. All the
cases on this wheel must play in an oblique direction downwards, and
burn two at a time; and those on the large wheel, four at a time; i.
e. two of those on the top set of spokes, and two of those in the
bottom set of spokes.
The four first cases on the large wheel, and the two first on the
small, must be fired at the same time, and the brilliant fire at the
top, at the beginning of the last cases. The cases of the wheels may
be filled with a gray charge. When these wheels are completed, we
must have a strong iron spindle, four feet six inches long; and fixed
perpendicularly on the top of a stand. On this, we put the large
wheel, whose nave must have a hole quite through from the bottom to
the top. This hole must be large enough to turn easy round the bottom
of the spindle, at which place there must be a shoulder, to keep the
wheel from touching the stand. At the top of the spindle, put the
small wheel, and join it to a large one with a leader, in order that
they may be fired both together.
_Pin wheels_, as they are called, are formed by rolling some paper
into pipes of about fourteen inches in length. The paper should be
thin, and rolled of three thicknesses. When they are thoroughly
dried, procure a tin tube, twelve inches long, to fit easy into the
pipes. At one end of this tube, fix a small conical cup, which cone
is called a funnel; then bend one end of one of the pipes, and put
the funnel in at the other, as far as it will reach, and fill the
cup with composition. Draw out the funnel gently, shaking it up and
down, and it will fill the pipe, as it comes out. Having filled some
pipes, procure some small blocks, about one inch in diameter and half
an inch thick. Round one of these blocks, wind and paste a pipe, and
to the end of this pipe, join another, which must be done by twisting
the end of one pipe to a point, and putting it into the end of the
other with a little paste. In this manner, join four or five pipes,
winding them one upon another, so as to form a spiral line. Having
wound on the pipes, paste two strips of paper across them to hold
them together. The pipes must also be pasted together.
The other method of making these wheels is described thus: wind on
the pipes without paste, and stick them together with sealing wax
at every half turn; so that, when they are fired, the end will fall
loose, every time the fire passes the wax, by which means the circle
of fire will be considerably increased.
The formers for these pipes are made from 1-1/2 to 4/16ths of an inch
in diameter. They may be fired on a large pin, and held in the hand
with safety.
_Composition for Pin-Wheels._
Meal-powder, 8 oz.
Saltpetre, 2 --
Sulphur, 1 --
Steel-filings, or the powder of cast-iron, ¼ --
The ingredients are to be well mixed, and dry. The mixture need not
be very fine, or it will adhere to the funnel.
_Sec. III. Of Revolving Suns._
From what has been said in the preceding section, it is obvious, that
revolving or turning suns may be formed, or any piece put in motion,
in the manner already described. The most common mode of forming
a sun, is to attach to three naves, which proceed from a hub, that
revolves on a spindle, from three to six cases, placing them in such
a way, that they may be fired successively. The jets, or spouts,
proceeding from the cases, constitute the _rays_, the sun being in
the centre, which revolves with the cases on an axis. The arrangement
of these cases should be such, as that the six (as that number is
usually employed,) might form the perimeter.
The cases may be charged with one, or with different compositions,
given in the following table. They are attached in such a way, that
the head of the first is nearly in contact with the _ray_ of the
second, and that to the third, &c. When the first case is finishing,
it must, therefore, communicate fire to the second, that to the
third, and so on in succession. These cases must be attached firmly
by wire; and leaders are used to communicate the fire, as in other
works. The end must be enclosed in the neck of the first case, and
the other end in that of the second, &c. They are secured in their
respective positions, by tying them securely to the cases.
With respect to the composition employed, it may be varied according
to pleasure. In most instances, however, the ordinary sun-composition
is used; but, in other instances, this is varied according to
circumstances. Morel has adopted the following composition for a sun
of six cases, the cases being eight-twelfths of an inch in diameter.
These cases are mounted on the arms of the sun in the same manner as
before described.
_Composition for a sun with variations, the cases of which are
eight-twelfths of an inch in caliber._
_No. 1, first change,_
Saltpetre, 16 oz.
Sulphur, 6 --
Meal-powder, 3 --
_No. 2, second change,_
Composition No. 1, 2 oz.
Meal-powder, 2 --
_No. 3, third change,_
Composition No. 2, 1 oz.
Meal-powder, 1 --
_No. 4, fourth change,_
Composition No. 3, 1 oz.
Meal-powder, 1 --
_No. 5, fifth change,_
Composition No. 4, 1 oz.
Meal-powder, 1 --
_No. 6, sixth change,_
Meal-powder alone, for two changes.
It appears evident, that the changes thus produced are owing to the
diminution of the quantity of saltpetre and sulphur, or, in other
words, to the increase of the quantity of powder; and that the fourth
change must contain but a small quantity of each, whilst the sixth or
last change contains none, except that which is in the composition
of the powder. The effect, therefore, must be proportionate; for, it
must be apparent, that this diminution of nitre and sulphur, and the
increase of powder, must render each charge more explosive, or, in
other words, the combustion more instantaneous, and that this effect
characterizes each of the changes in succession, is a result which
necessarily follows.
The instructions given by Morel for employing these changes, in
the charging of cases, are thus: We take the above composition for
the third case of the sun. The first case is of common fire; the
second of silver rain; the third of two charges of common fire, and
afterwards a charge of No. 1, the second two charges of No. 2, the
third three charges of No. 3, the fourth four charges of No. 4, the
fifth four charges of No. 5, and two charges of No. 6. The fourth
case is composed of brilliant fire; the fifth the same as the third,
and the sixth of large or grand jessamine.
We may merely remark, that the sun must be supported very firmly, and
that it ceases to revolve at the fourth, fifth, and sixth numbers.
_Sec. IV. Of Fixed Suns._
Fixed suns are so called, because they remain stationary, and exhibit
the appearance of a sun with innumerable rays. A fixed sun is formed
by putting eight or more strips of board across each other, so that
each arm may proceed from a common centre, in which a sun is painted
on silk. To the extremities of these arms are attached, to each one
in succession, a case of brilliant fire, which, by means of bodies
fixed in the usual manner, go off together. The two arms below,
forming right angles with each other, are longer than the rest; so is
also the upper and vertical arm. This, however, depends upon fancy.
The cases are tied to these arms; and, after the leaders are fixed
from the mouth of one case to that of the other, they terminate
at the bottom and hang below the vertical arm. Fire is first
communicated to the hanging match.
Fixed suns are usually employed as a decoration for other works. They
are sometimes sixty feet in diameter, and variously decorated. They
are commonly, however, ten feet. The fire extends a considerable
distance, sometimes, it is said, to the distance of thirty feet; but
this must depend on the size of the cases.
_Sec. V. Of Fixed Suns with Transparent Faces._
Fixed suns may be made with transparent faces in the following
manner: Two rows of cases must be fixed in radii from the face of
the sun, the sun being in the centre; and these cases, being placed
alternately one above the other, and preserving the same distance
all round, present what is called a double glory, and make the rays
strong and full. The frame or sun-wheel is made thus: Have a circular
flat nave, made very strong, 12 inches in diameter, and fix six
strong flat spokes, proceeding from the circle that contains the
sun's face to the extremity of the wheel, and also two other hoops,
placed between it and the sun. To these, and the external wheel, the
cases are tied. When the cases are tied on, leaders are attached from
the upper to the under cases. The front of these spokes supports a
circular fell, five feet in diameter. Within this is another fell,
smaller in diameter by the length of one of the sun cases; and within
this also is a third fell, whose diameter must be less than the
second by the length of one case and one third. The fells are divided
into as many equal parts as we employ cases, which may be from
twenty-four to forty-four. At each division, fix a flat iron staple.
These staples must be made to fix the cases and hold them fast on the
wheel. The staples must be so placed, that one row of cases may lie
in the middle of the intervals of the other. There is a spindle in
the centre of the block of the sun, to which a small hexagonal wheel
is put. The cases of this wheel must be filled with the same charge
as the cases of the sun. Two cases must burn at a time, and begin
with them on the fells. The pipes of communication are to be carried
from one to the other, and from one side of the sun to the wheel in
the middle, and from thence to the other side of the sun. They will
hold the wheel steady, when the sun is fixing up.
A sun thus made is called a brilliant sun, as there appears nothing
but sparks of brilliant fire, the wood-work being covered with fire
from the wheel in the middle. A transparent face is usually made with
pasteboard, by cutting out the eyes, nose, and mouth, for the sparks
of the wheel to appear through. A face may be painted on oiled paper,
or Persian silk, put over a hoop, and supported by three or four
pieces of wire at six inches distance from the wheel in the centre.
The silk may be painted according to fancy.
As to the size of cases for a sun of five feet in diameter,
half-pound cases, filled ten inches with composition, is considered a
good proportion.
_Sec. VI. Of the Rose-Piece and Sun._
This exhibition may be made in such a manner as to produce a pleasing
effect. A rose-piece may be used for a mutation, or change of a
regulated piece, or fixed by itself. It makes the best appearance,
when made large. If its exterior diameter be six feet, it will be a
good size. Let the exterior fell be made of wood, and supported by
four wooden spokes. All the other parts, on which the illuminations
are fixed, must be made of strong iron-wire. On the exterior fell,
place as many half pound cases of brilliant charge, as will be
sufficient; but the more, the greater will be the effect, for the
nearer the cases are placed, the stronger will be the rays of the
sun. The illuminations should be placed within three inches of each
other. They must all be fired together, and burn some time before
the sun is lighted, which may be done by carrying a leader from the
middle of one of the illuminations to the mouth of one of the sun
cases.
_Sec. VII. Of the Manner of changing a Horizontal to a Vertical
Wheel, and representing a Sun in front._
In order to produce this change, the wheel for this purpose should
be about three feet in diameter, and its fell circular, on which tie
sixteen half-pound cases, filled with brilliant charge. Two of these
cases must burn at a time. On each end of the nave is to be a tin
barrel of the same construction as those on the regulated piece.
We must then have a stand, made of any height, about three or four
inches square, and saw off from the top a piece two feet long. This
piece is then to be joined again, at the place where it was cut, with
a hinge on one side, so that it may lift up and down in the front of
the stand. Then fix on the top of the bottom part of the stand, on
each side, a bracket, which must project, at right angles with the
stand, one foot from the front, for the short piece to rest on. These
brackets are to be placed a little above the joint of the post, so
that, when the upper stand falls, it may lie between them at right
angles with the bottom stand; which may be done by fixing a piece of
wood one foot long between the brackets, and even with the top of
the bottom stand. Then, as the brackets rise above the bottom stand,
they will form a channel for the short post to lie in, and keep it
steady without straining the hinge. On the side of the short post,
opposite the hinge, nail a piece of wood of such a length, that, when
the post is perpendicular, it may reach about one and a half feet
down the long post; to which, being tied, it will hold the short
stand upright. The stand being thus prepared, in the top of it, fix a
spindle ten inches long. On this spindle put the wheel; then fix on a
brilliant sun, with a _single glory_. The diameter of this sun must
be six inches less than that of the wheel. When we fire this piece,
attention must be paid to light the wheel first, and let it run
horizontally till four cases are consumed. Then, from the end of the
fourth case, carry a leader into the tin barrel that turns over the
end of the stand. This leader must be met by another, brought through
the top of the post, from a case filled with a strong port-fire
charge, and tied to the bottom post, with its mouth facing the pack
thread, which holds up the stand; so that, when this case is lighted
it will burn the pack thread and let the wheel fall forward, by which
means it will become vertical. Then from the last case of the wheel,
carry a leader into the barrel, next the sun, which will begin as
soon as the wheel is burnt out.
_Sec. VIII. Of Caprices and Fire-Wands._
Caprices are so called from the particular motion they assume, and
are regulated according to the order and manner of their firing.
A perpendicular shaft, or post, is first provided, in which are
placed two sets of spokes at some distance from each other. At the
extremities of these spokes, joints are made, on which the cases
are fixed. These cases communicate with each other by leaders. The
first which takes fire, discharges upwards; the second, vertically;
the third, horizontally; and the fourth, fifth, sixth, and seventh,
go off at the same time; _viz._ the fourth, upwards; the fifth,
vertically, a little inclined; the sixth, horizontally; and the
seventh, vertically. The match of communication is fixed by a
port-fire.
The arrangement of this piece, to produce the effect, depends on the
construction of the wood work.
The great falling caprice differs from the foregoing in the following
particular, that it separates itself in the midst of its fire into
three parts. It is formed of three wheels, which appear as one; but
at a certain time after the fire is communicated, they separate and
occupy certain positions.
Mercury's Wand, as it is called, is formed by placing, across
each other, two pieces of wood, and at the extremity of each four
lances parallel to each other, and one obliquely. These lances
of illumination must be connected by leaders. Circular bands are
attached to the extremity of each leg, which terminates in the
centre, and the wings or legs move in opposite directions. The double
crescents, thus formed, produce, in turning, a variety of figures.
_Sec. IX. Of Palm and other Trees._
The representation of trees is considered an elegant fire-work. Palm
trees are shown by fixing an upright piece, which serves as a trunk,
and attaching to it a number of pieces, resembling in effect the
branches of a tree. The extremities or branches are decorated with
gerbes, and sometimes with marrons, arranged in such a manner that
they may go off together.
For Yew trees, cases of brilliant fire, jessamine, or Chinese are
used. In making this representation, the upright piece is usually
four feet in length, two inches in breadth, and one inch thick. At
the top we fix, on the flat side, a hoop fourteen inches in diameter,
and round its edge and front, place illuminations, and in its centre
a five-pointed star. At a foot and a half from the edge of the hoop,
two cases of brilliant fire are usually placed, one on each side.
These cases should be one foot long each. Below these are usually
fixed two more cases, at such a distance that their mouths may almost
meet those at top. Two other cases are sometimes added, which
ought to be parallel with the last. The cases are then clothed with
leaders, so that they, with the illuminations and stars at top, may
all take fire together.
Fire trees may be formed by placing cases at an angle of 45 degrees,
inclining upwards from the trunk, and at certain distances from each
other. The two last cases may incline downwards. Cases may also be
placed on the trunk itself, so that the whole will resemble a body
of fire. Fire trees are commonly made about six feet long and three
inches in diameter. The cases are generally fixed to pegs. At the
top of the tree, a four-inch mortar is fixed, which is loaded with
stars, rains, or crackers. In the middle of this mortar, we may place
a case filled with any sort of charge, which must be fired with
the other cases. Brilliant fire is generally employed. The fire is
communicated, as in other works, by means of leaders, which are fired
at the bottom.
There is also another exhibition often made with the so called
_illuminated yew-tree_. The middle piece or stem on which the
branches are placed, is generally eight feet six inches high.
The branches all incline downward, and shorten as they go up.
The number of branches on each side is six, and their length is
determined according to judgment. When the branches are fixed, place
illuminating port-fires on the top of each, as many as are required.
Behind the top of the stem, fasten a gerbe or fountain of Chinese
fire, which must be fired at the beginning of the illuminations on
the tree.
Fires are often made to intersect each other, which has a good
effect. For this purpose a perpendicular post is provided, of any
thickness, so that it is sufficiently strong to hold the cases.
There are two pieces of wood which go across the post, two feet six
inches apart and two feet in length. On the end of each of these
pieces there is usually a five-pointed star. Six stars are mostly
employed. Pegs are fixed to the post in such a way that two of them
incline upwards and two downwards, both forming an angle of ninety
degrees, or forty-five degrees with the post. To these pegs are fixed
half pound cases of brilliant fire. All the cases and stars must be
fired at once. It is obvious that by this arrangement of the cases,
the fires must cross, and thus by intersecting each other afford a
greater variety.
_Sec. X. Of the Pyramid of Flower Pots._
This piece is formed by attaching to a post, ten or twelve feet high,
and placed perpendicularly in the ground, four rails or pieces,
two feet apart, which must diminish in length, so as to represent a
pyramid. The bottom rail must be six feet long. On the bottom rail
fix five paper mortars, each three and a half inches in diameter. Let
one be opposite the post, and the other four equally distant on each
side. Load these mortars with serpents, crackers, stars, &c. In the
centre of each mortar fix a case of spur-fire. On the second rail fix
four mortars so as to stand exactly in the middle of the intervals
of those on the bottom rail. On the third rail, place three mortars,
on the fourth, two; and on the top of the post, one. All the mortars
must incline a little forwards, that they may easily discharge; and
the spur-fire rammed exactly alike, that the mortars may all be fired
at the same time. The pipes of communication being prepared, carry
them from one spur-fire to the other.
_Sec. XI. Of the Dodecaedron._
The piece, required in forming a twelve sided figure, is prepared
in the following manner: A ball must be turned out of solid wood,
fourteen inches in diameter, and its surface is to be divided into
fourteen equal parts. In each division bore holes of a half inch in
diameter, perpendicular to the centre, so that they may all meet in
the middle. In the inside of each hole, let there be turned a female
screw. To all the holes but one must be made a round spoke, five feet
long, with four inches of the screw at one end to fit the holes. In
the screw end of all the spokes, bore a hole five inches up, which
must be bored slanting so as to come out at one side a little above
the screw. From these holes cut a small groove along the spoke,
within six inches of the other end, where another hole through to the
other side of the spoke is made. To this end fix a spindle, on which
put a small wheel of three or four sides, each side six or seven
inches long; these sides must have grooves cut in them, large enough
to receive a two or four-ounce case. When these wheels are clothed
put them on the spindles, and at the end of each spindle attach a nut
to keep the wheel from falling off.
The wheels being thus fixed, carry a pipe from the mouth of the
first case on each wheel through the hole in the side of the spoke,
and from thence along the groove and through the other hole, so as
to hang out at the screw end about an inch. The spokes being all
prepared in this manner, a post must be provided on which the piece
is to be fired, having an iron screw in the top of it to fit one
of the holes in the ball. On the screw attach the ball and then in
the top hole of the ball put a little meal-powder, and some loose
quick-match. After this, screw in all the spokes, and in one side
of the ball bore a hole, in which put a leader and secure it at the
end. By this leader the powder and match in the centre are fired,
which will light the match at the end of the spokes all at once, and
by which all the wheels will be lighted at the same time. There may
be an addition to this piece by fixing a small globe on each wheel,
or one on the top wheel only. Gray charge may be used for the wheel
cases.
_Sec. XII. Of Cascades of Fire._
Cascades of fire may be made of any size, and with cases from a half
pound to a pound, or more. Half pound cases are usually the size
employed. Cascades may be made either fixed, or turning. The former
are an assemblage of pieces of wood, furnished with cases charged
with Chinese fire, and placed one above the other. The distance may
be more or less; sometimes from eight to fifteen feet. The latter,
or turning cascades, are constructed about four feet in diameter.
The wheel is made to turn on a pivot, and is put in motion by
attaching to it, in the usual manner, cases of white fire. These
play horizontally. The cases of Chinese fire, which play downwards,
are fixed to the wheel, or to another wheel below this, or above
it, according to fancy, and are placed with their mouths downwards.
Sometimes in fact they play upwards, and for that purpose are made to
incline outwards. In the centre, there is a case or two of brilliant
fire.
It is obvious, that this arrangement not only gives a motion to the
wheel, and to the cases of Chinese fire, but produces in effect a
circular sheet, which falls like a cascade.
By having an upright piece, stuck in the ground, on which are fixed
three or more horizontal wheels, or segments of a circle, made
permanent, and at about three feet from each other, diminishing,
however, as they go up, and also in their diameter, a frame will be
formed capable of holding a great number of cases. The first segment
may be four feet in diameter. The top pieces may be of any length,
so as to hold the cases at a little distance from each other. All
the cross pieces are to be fixed horizontally, and supported by
brackets. The bottom cross piece, or segment, should be about one
foot six inches broad in the middle; the second, one foot; the third,
nine inches; and the top piece, four inches. The cases may be made
of any length, but must be filled with a brilliant charge. Bits of
wood ought to be nailed on the edges of the cross pieces, having a
groove cut in each piece, and sufficiently large for a case to lie
in. These bits of wood are fixed, so as to incline downwards, and
that the fire from one tier of cases may play over the other. Leaders
are carried from one to the other, as before mentioned. Let there be
a pipe, hung from the mouth of one of these cases, covered at the
end with a single paper, which is burnt to fire the cascade. Nine
cases generally form the first tier; seven, the second, four, the
third; and three, the last. These cases play downwards, except the
three at top, one of which is vertical and the other two inclining at
an angle of about forty-five degrees. The arrangement may be varied
at pleasure. The only thing to be attended to is, to fix the cases
in such a way, that the fire which proceeds from them may pass over
the tier immediately underneath, that the effect may be general and
uniform. Chinese fire may be used, as in the former instance.
_Sec. XIII. Of Chinese Fountains, and Parasols._
The manner of constructing the wood work of a Chinese fountain is as
follows: Procure a perpendicular piece of wood, seven feet long, and
two and a half inches square. At sixteen inches from the top, fix on
the front a cross piece, one inch thick, and two and a half inches
broad; with the broad side up. Below this, fix three more pieces of
the same width and thickness, at sixteen inches from each other. Let
the bottom rail be five feet long, and the others of such a length as
to allow the fire-pumps to stand in the middle of the intervals of
each other. The pyramid being thus made, fix in the holes, made in
the bottom rail, five fire-pumps, at equal distances: on the second
rail, place four pumps; on the third, three; on the fourth, two; and
on the top of the post, one. Place them all, however, to incline a
little forward, so that when they throw out the stars, they may not
strike against the cross rails. The fire-pumps are to be clothed with
leaders, in order that they may all be fired together.
Cases for _Fire-pumps_ are made in the same manner as those for
tourbillons. See _Fire-pump_, and also _Fire-pots_ of various kinds.
The effect of these cases depends entirely on the star-composition.
Stars, previously moulded, are introduced into them along with
meal-powder.
Parasols are also formed with Chinese fire. A horizontal wheel is
provided, and its circumference is clothed with eight or ten cases
of that fire. These cases may be five-sixths of an inch in diameter,
and, when inflamed, should throw their fire horizontally. The fire,
in this instance, is made to resemble a _sheaf_; but the ordinary
composition is generally used. The cases, however, should play
horizontally. To make the wheel turn on its pivot, two cases of white
fire are attached to it. The parasol, produced by the fire, is from
twenty-five to thirty feet in diameter. It is formed in consequence
of the fire coming in contact, and producing a concave sheet in its
fall, resembling a parasol when extended.
_Sec. XIV. Of Wings or Cross Fire._
Nearly similar to one of the pieces described, that of the
representation of a tree, is the cross-fire, or _wings_, a name given
to it, because it resembles the sails, or wings of a windmill.
In forming this piece, two sticks, eight feet in length, are
provided, and through the centre of each, a square hole is made, to
receive a piece of iron of the same size, through which is a hole to
admit a pivot.
When these sticks are put together, there must be a sufficient
distance between them to prevent their rubbing each other. Five
cases, charged with the composition of brilliant fire, are fixed to
each extremity, proceeding towards the centre, at a short distance
apart, and making in all twenty cases. Four of these cases are
placed at each end, nearly horizontally, resembling the rounds of a
ladder, the sticks being nearly vertical; and the one nearest the
centre is placed almost vertically, or rather obliquely. The cases,
being connected with leaders, when fired, turn with the sticks in an
_opposite_ direction to each other.
When three wheels are each furnished with two rounds of white and
coloured fire, and are so arranged, that the periphery of each should
pass over in succession at the distance of ninety degrees of the
perimeter, this piece is then called by the whimsical name of the
_love-knot_.
_Sec. XV. Of Galleries of Fire, and Batteries of Roman and Mosaic
Candles._
Galleries of fire are formed by attaching, to long strips of wood,
at convenient distances from each other, cases of Chinese fire, which
go off together. At the end of each case, is put a marron, which,
when the case is burnt, ends with an explosion.
To form batteries with marrons, in connection with Roman candles,
they are tied at two feet distance from each other, on long sticks,
leaders being attached. These batteries, like the fire gallery,
usually accompany other fire-works.
We may here remark, that _thunder_ is imitated by marrons, which are
fixed in the same way two feet apart. To produce the effect, and
increase the report, it is necessary to use them of different sizes,
from a quarter of an inch to three inches caliber. They should be
preceded by flashes of _lightning_, which is imitated either with
powdered rosin, or lycopodium, in the manner described in our chapter
on _Theatrical Fire-Works_.
_Sec. XVI. Of Girandoles, and their Modifications._
Girandoles, for the purpose here noticed, are nothing more than
wheels which turn on a pivot. They are made of light wood, with a rim
similar to that of a sieve, and are clothed with cases. Two cases are
fired at a time, which burn in an opposite direction.
Girandoles may be made to imitate a parasol, by placing,
horizontally, cases charged with the blue-fire composition, or with
that of the Chinese fire. Cascades may be formed, by arranging them
vertically, horizontally, and some at an angle of ten or fifteen
degrees from the horizon. The _bunch of flowers_ is represented
by using, at the same time, cases of 10/12ths, 11/12ths, and one
inch, charged with Chinese composition, as given in the table for
calibers of that diameter. See _Chinese Fire_. Crackers are formed by
attaching Roman candles and Mosaic simples, and the sheaf is shown
by fixing in the centre some empty cases, on which are strung small
rockets, which are fired by the last case.
There are different modes of varying the effect of the girandole.
They may imitate the fire-rain, by employing cases charged with that
composition, which is given in the chapter on _Theatrical Fire-Works_.
_Sec. XVII. Of Cracking Caprices._
For this piece, a circular table is formed about twenty inches in
diameter, and one inch and a quarter thick. There is a hole made in
the centre, which is furnished with a pivot.
Twelve inches from the circumference, and at equal distances, eight
holes are to be bored, to receive the same number of pots, of two
inches caliber; and, in the immediate vicinity of the centre hole,
which receives the pivot, four more are made, for four other pots.
Eight arms, three inches long, project from the table at equal
distances, on which is fastened a hoop one inch in width. The
fire-pots are now put in the different apertures, which are made
sometimes to screw in; and the frame, of which we have spoken, is
furnished with cases of brilliant fire.
It is necessary that this piece should go off at three fires; but the
order of firing may be varied according to circumstances.
_Sec. XVIII. Of the Projected Regulated Piece of Nine Mutations._
A regulated piece, if well executed, is considered as curious in its
effect as any other in pyrotechny. It consists of fixed and moveable
pieces on one spindle, representing various figures, which take fire
successively one upon another, without any assistance after lighting
the first mutation.
I. Names of the mutations, with the colour of fire, and size of the
case, belonging to each.
_First Mutation._--This is a hexagon vertical wheel, illuminated in
front with small port-fires, tied on the spokes. This wheel must be
clothed with two-ounce cases, filled with black charge. The length
of these cases is determined by the size of the wheel, but each must
burn singly.
_Second Mutation._--This is a fixed piece, called a golden glory,
by reason of the cases being filled with spur fire. The cases must
stand perpendicular to the block, on which they are fixed, so that,
when burning, they may represent a _glory_ of fire. This mutation is
generally composed of five, or seven two-ounce cases.
_Third Mutation._--This is moveable, and is only an octagon vertical
wheel, clothed with four-ounce cases, filled with brilliant charge.
Two of these cases must burn at a time. In this wheel, we may make
changes of fire.
_Fourth Mutation._--This is a fixed sun of brilliant fire, consisting
of twelve four-ounce cases. The necks of these cases must be a little
larger than those of four-ounce wheel cases. In this mutation, may
be made a change of fire, by filling the cases half with brilliant
charge, and half with gray.
_Fifth Mutation._--This is a fixed piece called the _porcupine
quills_. This piece consists of twelve spokes, standing perpendicular
to the block in which they are fixed. On each of these spokes, near
the end, must be placed a four-ounce case of brilliant fire. All
these cases must incline either to the right or left, so that they
may all play one way.
_Sixth Mutation._--This is a standing piece called the cross fire.
This mutation consists of eight spokes fixed in a block. Near the end
of each of the spokes, must be tied two four-ounce cases of white
charge, one across the other; so that the fires from the cases on one
spoke may intersect the fire from the cases on the other.
_Seventh Mutation._--This is a fixed wheel with two circular fells,
on which are placed sixteen eight-ounce cases of brilliant fire, in
the form of a star. This piece is called a fixed star of _wild fire_.
_Eighth Mutation._--This is a beautiful piece, called a brilliant
star piece. It consists of six spokes, which are strengthened by two
fells of a hexagon form, at some distance from each other. At the
end of each spoke, in the front, is fixed a brilliant star of five
points; and on each side of every star is placed a four-ounce case of
black or gray charge. These cases must be placed with their mouths
sidewise, so that their fires may cross each other.
_Ninth Mutation._--This is a wheel piece. It is composed of six
long spokes, with a hexagon vertical wheel at the end of each.
These wheels run on spindles in front of the spokes. All the wheels
are lighted together. Two-ounce cases will be sufficient for these
wheels, and may be filled with any coloured charge.
II. With respect to the proportion of these mutations, with the
method of conveying the fire from one to the other, and the distance
they stand from each other on the spindle, the following general
remarks will be sufficient.
The _first mutation_ must be a hexagon vertical wheel fourteen
inches in diameter. On one side of the block, whose diameter is two
and one-fourth inches, is fixed a tin barrel. This barrel must be a
little less in diameter than the nave. Let the length of the barrel,
and block be six inches. Having fixed the cases on the wheel, carry a
leader, from the tail of the last case, into the tin barrel, through
a hole, made on purpose, two inches from the block. At the end of
this leader, let there be about one inch, or two, of loose match; but
be careful to secure the hole, in which the pipe is put, to prevent
any sparks falling in, which would light the second mutation before
its time, and confuse the whole.
The _second mutation_ is thus made. Have a nave, turned two and a
half inches in diameter, and three long; then let half an inch of
that end, which faces the first wheel, be turned, so as to fit easy
into the tin barrel of the first mutation, which must turn round it
without touching. On the other end of the block, fix a tin barrel
No. 2. This barrel must be six inches long, and only half an inch of
it to fit on the block. Round the nave, fix five spokes, one inch
and a half long each. The diameter of the spokes must be equal to
a two-ounce former. On these spokes, put five seven-inch two-ounce
cases of spur-fire, and carry leaders from the mouth of one to the
other, that they may all light together. Then, from the mouth of one
of these cases, carry a leader through a hole bored slantwise in the
nave, from between the spokes to the front of the block, near the
spindle hole. The end of this leader must project out of the hole
into the barrel of the first mutation; so that, when the pipe, which
comes from the end of the last case on the first wheel, flashes, it
may take fire and light the second mutation. To communicate the fire
to the third mutation, bore a hole near the bottom of one of the five
cases to the composition; and from thence carry a leader into a hole,
made in the middle of the barrel. This hole must be covered with
pasted paper.
The _third mutation_ may be either an octagon or hexagon wheel,
twenty inches in diameter. Let the nave be three and a quarter inches
in diameter, and three and a half in length. One and a half inches of
the front of the nave must be made to fit in the barrel No. 2. On the
other end of the block, fix a tin barrel No. 3. This barrel must be
six and a half inches in length, one inch of which must fit over the
block. The cases of this wheel must burn two at a time, and, from the
mouths of the two first cases, carry a leader through holes in the
nave, into the barrel of the second mutation, after the usual manner.
But besides these leaders, let a pipe go across the wheel from one of
the first cases to the other. Then, from the tail of one of the last
cases, carry a pipe into a hole in the middle of the barrel No. 3: at
the end of this pipe, let there be some loose quick match.
_Fourth and Fifth Mutations._--Their naves are made of one piece,
which, from the barrel of the fourth, to the commencement of the
sixth, is fourteen inches. The block of the fourth is four inches
in diameter, having ten or twelve short spokes, on which are fixed
eleven inch eight-ounce cases. The front of this block must fit easy
in the barrel of the third wheel. Clothe the cases, so that they
may all light together; and let a pipe be carried through a hole in
the block into the barrel No. 3, in order to receive the fire from
the leader, brought from the last case on the wheel. The nave of
the fifth mutation must be four and a half inches in diameter, and
furnished with ten or twelve spokes, eighteen inches in length each.
These spokes must stand seven inches distant from the spokes of the
fourth mutation, and, at the end of each spoke, tie a four-ounce case
as No. 5. All these cases are to be lighted together, by a leader
brought from the end of one of the cases on No. 4.
_Sixth and Seventh Mutations._--The blocks of these two mutations are
turned out of one piece of wood, whose length from the barrel of the
fifth wheel, to the block of the eighth wheel, is fifteen inches.
The block of the sixth wheel is five inches in diameter, having
eight spokes, each two feet four inches long. At the end of each
spoke, tie two four-ounce cases, as in No. 6. All these cases must
be fired at the same time, by a pipe brought from the end of one of
the cases on the fifth mutation. Let the distance between the spokes
of the sixth, and those in the fifth mutation, be seven inches.
The nave of the seventh mutation must be five and a half inches in
diameter, and furnished with eight spokes. On the front of them, two
circular fells, one of four feet eight inches in diameter, and the
other, three feet eleven inches, are to be fixed. On these fells, tie
sixteen eight-ounce cases, or pound cases, as in No. 7, and carry
leaders from one to the other, so that they may be fired at the same
time. This mutation must be fired by a leader, brought from the tail
of one of the cases on the sixth mutation.
_Eighth and Ninth Mutations._--The blocks of these may be turned out
of one piece, whose length from the barrel of the seventh mutation
to the block of the ninth, must be twelve inches. The block of the
eighth, six inches in diameter, must contain six spokes, each three
feet in length, and strengthened by an hexagon fell, within three
or four inches of the ends of the spokes. Close to the end of each
spoke, in the front, fix a five-pointed brilliant star, and seven
inches below each star, attach two ten-inch eight-ounce cases, so
that the upper ends of the cases may rest on the fells, and their
ends on the spokes. Each of these cases must be placed parallel to
the opposite fell.
_Ninth Mutation._--The block of the ninth mutation is seven inches
in diameter, and holds six spokes, six feet long each, with holes
and grooves for leaders, as those in the dodecaedron. At the end of
each spoke in the front, fix a spindle for a hexagon vertical wheel,
ten inches in diameter, as in No. 9. When these wheels are on, carry
a leader from each into the block, so that they may all meet. Then
lead a pipe from the end of one of the cases of the eighth mutation,
through a hole bored in the block of the ninth, to meet the leaders
from the vertical wheels, in order that they may be fired together.
Having thus given a brief description of this complicated work, the
performance of which depends so much on the accuracy of its parts, we
will now add a few remarks respecting the formation of spindles.
For the larger pieces, the spindles should be made very strong
and exact. The instructions on this head are, that for a piece of
nine mutations, let the spindle be, at the large end, one inch in
diameter, and continue that thickness as far as the seventh mutation,
and from thence to the fifth, let its diameter be three-quarters of
an inch. The other proportions, then, are, from the fourth to the
second, half an inch; and from the second to the end, three-eighths
of an inch. At the small end must be a nut, to keep on the first
wheel, and at the thick end, a large nut; so that the screw part of
the spindle being put through a post, and a nut screwed on tight, the
spindle will be held fast and steady. The wheels, however, ought to
run easy and without sticking. The fixed pieces are made on different
blocks, and the leaders must be joined, after they are fixed on the
spindle. The best method of preventing the fixed mutations from
moving on the spindle, is to bore a hole a little larger than the
diameter of the spindle; and, at each end of the block, over the
hole, fasten a piece of brass, with a square hole in it to fit the
spindle.
Similar to this piece of nine mutations is the _Pièce Pyrique_ of the
French, which consists of a great variety of fixed and moving pieces,
that are fired alternately, but in regular succession. This piece we
purpose to describe in the following section.
_Sec. XIX. Of the Pyric or Fire-Piece._
This, we have remarked, is a combination of pieces, calculated, like
the one we have described, to produce a variety of fires, variously
arranged and distributed.
The pyric piece commonly commences with a turning sun. This sun
consists of three cases, fixed to three arms proceeding from the
centre. They are attached by means of a string, and have leaders
which go from one to the other of the cases. See _Sun_. This sun
communicates its fire to a fixed sun, formed of eight or nine strips
of board, crossing each other, or as many spokes from a hub, to which
are attached, lengthwise, as many cases, whose mouths are made to
communicate fire by means of leaders; so that each case presents the
appearance we have before described. Then follows a wheel consisting
of two or more concentric circles, and round which are placed eight
cases, with their mouths inclining a little upwards. These cases are
generally charged with brilliant fire. They communicate with each
other in the usual manner, and afterwards with a fixed star, placed
on a stick, proceeding from the horizontal axis. This star is made
of two cases, charged with Chinese fire, with their mouths upwards,
and forming, with each other, an angle of forty-five degrees. This
fire is then communicated to another wheel, and from that to one, on
which, at certain distances, are fixed six smaller wheels, furnished
with six cases each; so that the whole are put in motion at one time,
the fire being communicated at the same period. The appearance of
these smaller wheels, as the cases may be charged with the coloured
fire-composition, is such as to exhibit the motion of a screw; which,
however, depends on the structure of the wheel. The fire from this
may then communicate to other wheels of the same kind, to cases
of brilliant fire, to marrons and the like, differently arranged
according to fancy. Cylinders of copper or tin, called _barrels_ by
some, are used in the arrangement, in the manner already described.
In fact, the remarks we have before made on the regulated piece of
nine mutations, the manner of forming as well as of executing it,
will apply to the Pyric-piece.
_Sec. XX. Of Sundry Illuminated Figures._
There are various illuminated pieces, some of which we purpose to
notice in this section.