COMPOUND FIREWORKS
Compound fireworks are those which are composed of a number of simple
fireworks or units fixed to a framework or other device so that they
produce a more elaborate effect than do single fireworks.
Probably the earliest form of compound firework was the wheel. After
the sky rocket had become an established fact, it was a small step to
tie rockets round a wheel, so that when fired they caused it to revolve.
Babington gives several devices based on the idea of imparting
movement to a wheel by rockets: he describes horizontal and vertical
wheels, which appear to be the same piece fired either horizontally or
vertically. In neither case is there any further effect than the fire
from the rockets tied to the periphery. His illustration shows no less
than sixteen rockets to fire singly in succession, which would, by
modern standards, make a rather lengthy and monotonous piece. He also
describes ground wheels, which consist of two wheels fitted to an axle
with a smaller wheel placed centrally between them. The centre wheel
has rocket cases fitted to it, causing the whole arrangement to revolve
and run along the ground. As an alternative he suggests substituting
cases secured to the axle without a central wheel, so arranged that one
being burnt out the second burns in the opposite direction and reverses
the direction of the wheels. The device is now quite obsolete.
One interesting point is the method of communicating fire from one case
to the next; quickmatch, as used to-day, had not then been invented.
His method was to fasten the cases head to tail a short distance apart
by wrapping and tying paper round in the form of a tube, the space so
formed containing some mealed powder.
He also describes what he calls fixed wheels, which are in effect the
fixed sun of to-day; that is, a framework with cases arranged radially
so that the fire is thrown out from the centre.
As variations of the above, he suggests various effects such as “a
fixed wheel which shall give divers reports,” “which shall cast forth
divers fisgigs, and likewise as many reports or breakers,” “which shall
cast forth many rockets into the ayre.” The latter is evidently the
prototype of a piece known later as the rocket wheel, popular for some
time, but little used at the present, the objection to it being that
there is no control over the direction in which the rockets fly from
it. The wheel revolves horizontally, and projects a series of rockets
into the air as it revolves.
During the following century, as compound fireworks developed in this
country, the Italian and French nomenclature was introduced, many of
which survive at the present time.
The pyrotechnists of the eighteenth century seem to have delighted in
inventing new terms, possibly with the idea of impressing the layman.
Frézier, writing over a hundred years later than Babington, records
very little advance in revolving fireworks, except in the matter of
names. He classifies all revolving pieces as girandoles. This word
appears in pyrotechny very frequently; curiously enough, nearly every
writer has attached a different meaning to it. Frézier explains that
the word is derived from girare—to revolve or gyrate, from the Greek.
Bate applied this meaning to it. He says, “How to make gironels or fire
wheeles.” He is, however, the only English writer to do so; others use
it to mean a flight of rockets, and occasionally for an elaborate fixed
piece of the fountain type.
Ruggieri and Sarti, both Italians, used it in the sense of a “flight”
of rockets in the programme of their Green Park display in 1749.
Ruggieri the younger, however, applies it to a specific kind of
revolving firework in his book, and introduces a new word—girande—to
which he applies the same meaning as the one generally accepted in this
country for girandole. The confusion of these two words, which have the
same derivation, may be the explanation of the duplication of meaning,
or it may lie in the fact that the name was also applied to the rocket
wheel previously mentioned, which both revolves and throws up rockets.
Frézier shows a wheel similar to that given by Babington, and
variations on the double saxon, a fixed sun also, as do most early
writers, double line rockets to run backwards and forwards and
variations. These latter, which appear to have been very popular at
this period, were known in France as “courantins.” Bate calls them
“swevels,” other early writers “runners on the line.”
The above-mentioned, together with some rather intricate but
impracticable appearing water devices, make up the compound fireworks
in Frézier’s book.
It seems, however, that he must have been behind his day in this
branch of the art, as the Aix-la-Chapelle peace display appears to
have included several elaborate pieces which, even allowing for the
usual exaggeration of the programme, must have required considerable
skill and knowledge in construction. These were mostly what were
called regulated or regulating pieces, generally described as of a
certain number of mutations. The pieces were, and are, although the
old descriptions are now dispensed with, so constructed that after
being lit they go through a series of alterations in form and movement
without further attention.
Some of those described in old works would seem to have required more
than a slight element of luck for their successful performance.
To-day it is often found more advantageous to make a second lighting in
cases where there is a danger of premature ignition, the effect to the
spectators being identical, and the successful functioning of the piece
secured. This does not apply to all pieces of this nature, as with
modern safety fuse the pyrotechnist has considerable advantage over the
earlier practitioners.
The modern spectator is only concerned with the effect produced, not
by the means adopted to produce it. It is difficult to-day to realise
the position occupied by the pyrotechnist of the eighteenth century. He
carried out his work personally, with of course trained assistants, and
occupied a position similar to the artist or sculptor. Each piece was
looked upon as a work of art, the personal effort of the pyrotechnic
artist. Ruggieri gives some idea of this in the following passage from
his book:
“It was in the month of July, 1743, that my father and my uncles
Ruggieri exhibited for the first time at the Theatre de la Comédie
Italienne and before the King, the passage of fire from a moving to
a fixed piece.
“This ingenious contrivance at first astonished the scientists of
the day, who said when it was explained to them that nothing could
be more simple and that any one could have done it at once.”
He then explains the method of construction, which is to lead from the
back end of one of the turning cases through the hollow centre of the
axle to the lighter of the fixed piece situated behind it.
The development of fixed and mechanical pieces was made possible by the
introduction of quickmatch.
When this actually took place is uncertain. Frézier describes its
making similarly to that in use to-day, under the name of “étoupilles.”
Bate uses the word “stouple,” evidently a corruption of the French.
He gives no actual description of the making of this, but it appears
to be of “cotton weeke” dipped in “aqua vitæ wherein camphire hath
been dissolved.” This would produce only a slow-burning match unless
it was his intention to use it wet, in which case the burning of the
spirits of wine might quicken the effect. It would, however, be quite
out of the question to construct a piece of any elaboration with such
materials.
Quickmatch is manufactured to-day in the following manner. Cotton wick
is run through a pan containing a paste composed of gunpowder and
starch. It is wound on a frame six feet in length, dusted with mealed
powder and dried. When dry it is cut off the frame and threaded into
paper tubes or “pipes” of larger diameter, leaving an air space round
the match.
Before threading in the tubes it is known in the trade as “raw match,”
and is used for priming and similar uses, and in this state will only
burn quite slowly.
Quickmatch is used to connect the units of all pieces. Display cases
have a “cap” formed of a few turns of paper pasted on the case at the
lighting end. When a piece is fitted up the cases are tied to the
cleats provided to receive them on the framework; they are then “lead
up.” A length of quickmatch has a small piece cut out of the pipe to
allow the fire to flash through, it is then doubled at that point and
inserted in the cap, which is gathered in and tied round securely.
This is continued round the piece, each case having match entering and
leaving the cap, and in some cases a further length connecting one
series with another. This leading up of set pieces is work requiring
skill and knowledge which is only gained by experience. An amateur at
a first attempt might possibly be successful in lighting all the cases
on a piece, but he would be very unlikely to produce that instant and
symmetrical ignition which denotes the skilled pyrotechnist.
The smaller wheels have turning cases, that is, small rockets to give
them motion; these burn through very rapidly, and the continuation of
movement is provided for by capping the turning cases at either end and
leading them up vent to head in series; the motive power for the larger
display pieces is provided by gerbs, which, from the nature of their
fire, give more effect than would rocket cases, and have the further
advantage of burning longer.
It would not be possible in the present work to give a complete
catalogue of the varieties of pieces which have been produced, but the
list given by Ruggieri is typical of the whole, and includes many of
the smaller compound pieces in use to-day for shop and small display
work.
The larger display pieces are generally designed and redesigned season
by season by pyrotechnists, and are certainly being elaborated and
improved. They, however, fall generally into certain classes in the
same way as do those given by Ruggieri. His classification is as
follows:
1. Stationary fireworks.
2. Fireworks turning vertically.
3. Mixed fireworks or fixed and turning.
4. Fireworks turning horizontally or on a pivot.
5. Built-up pieces turning on a pivot.
6. Cut-out pieces and transparencies.
Of these, the last mentioned class are now obsolete: they consisted of
transparent and silhouette pictures or designs illuminated from behind.
He also includes both simple and compound fireworks in each class, but
as the former have already been dealt with they will be ignored here.
Class 1. (1) Glorys, fans and “pates d’oie” or goose foot, synonymous
with our expression crow’s foot.
Glory was a term used also in this country to signify fixed suns, as
mentioned above. Fans were cases five or more in number, arranged as
the name indicated, and pates d’oie, three similarly arranged.
(2) Mosaiques. These are geometrical designs formed by arranging gerbs
or fixt on framework, so that their fire forms a symmetrical pattern.
The effect is heightened by saxons in suitable positions, and in large
devices of this nature, small wheels, also formerly, the now obsolete
fixed or five-pointed star.
This type includes what are now called “lattice poles,” a series of
poles provided with cleats so that the fire of the cases crosses,
forming a lattice of sparks; also the more elaborate “carpet piece.”
(3) Feux croisés. These were similar in conception to the above, except
that the design is circular or based on the circle or wheel form; this
type is represented by the “fixt piece” of to-day, which is constructed
up to considerable dimensions, the large fixt piece at the Crystal
Palace often measuring sixty feet across the fire.
(4) Palm Trees. These consist of a framework intended to suggest the
form of a palm, provided with cleats to take the cases.
(5) Bouquets. These he describes also as a kind of tree different from
palm trees; his illustration shows that they were similar to the modern
lattice-pole with the difference that the cleats were not symmetrically
arranged.
To-day the word bouquet is applied to Roman candles arranged in what he
called “pates d’oie.”
(6) Cascade. This device needs no explanation. He says that Chinese
fire is the best composition for such a piece; this remained true up
to the introduction of the aluminium into pyrotechny, when the “weird
white waterfall” became a feature of the Crystal Palace displays, being
200 feet long and 90 feet high.
(7) Decorations in coloured fire. This heading introduces the lancework
set piece of to-day.
The development of this branch since 1865 has been very marked. As will
be seen from the description of the lancework pieces carried out at
the Crystal Palace, the subjects dealt with have been of extraordinary
variety. Up to the beginning of the nineteenth century pyrotechnists
had failed to realise the possibilities of lancework. This was
undoubtedly due in a great measure to the fewness of colours available.
Ruggieri appears to have used lancework to outline architectural
designs, evidently a survival of the temples or theatres of earlier
years. In his time, and even as late as the middle of the nineteenth
century, any subject of a pictorial nature was depicted by the use
of scenery or transparencies. Lancework was, as Ruggieri describes
it, merely “decorations in coloured fire.” The lances of his day were
considerably thicker than those at present in use, which are about the
diameter of a lead pencil. They were also spaced further apart and were
in some cases “bounced,” as are fixed cases of the present day.
The modern method of constructing a lancework set piece is as follows:
An outline drawing of the subject is made in which all unnecessary
lines are eliminated. This is ruled in square of such size that in the
proportion one square to a foot the completed piece will be of the size
required.
Frames are then laid out on the drawing-floor: these are of light
battens forming foot squares, and of a convenient size for handling,
generally ten feet by five feet.
[Illustration: Lattice Poles.]
[Illustration: Chromatrope
(The outer fire forms the Guilloché of Ruggieri.)]
[Illustration: Lattice Diamond
(The Feux Croisés of Ruggieri.)]
The drawing is then transferred to the floor with the assistance of the
squared lines, and the design followed by nailing on light wood strips
or thin rattan cane.
The lines thus indicated are then “pegged,” that is, pegs or small
wire nails pointed at either end, are driven in at intervals of about
four inches. The lances, whose construction has already been described
in Chapter IV, have their ends glued and are pushed on to the pegs so
that they stand vertically from the framework. The frames are then led
up with quickmatch, secured by pins driven into the priming. The match
is then pierced with a small awl above the priming, and secured and
protected by a strip of paper pasted over it and round the case of the
lance. The piece is then ready for hoisting into position and firing.
Formerly, and sometimes now on the Continent, the match was secured by
a wire passing through the case near the top, which was twisted over
the match.
Ruggieri, under this head, describes a method of illuminating by
impregnating wick similar to that used for matchmaking, with a mixture
of sulphur, antimony, and saltpetre. This was wired on to a metal
framework. He says it is better than lancework for outlining curves,
volutes, etc., as the line is continuous. This difficulty is disposed
of in modern English lancework by the closer spacing of lances on
curves rendered possible by the smaller lances now used.
He also remarks that this method was rarely used in his time and it is
now quite discontinued.
Another device of which he seems proud was a palm tree, the leaves
of which were of thin metal from which project spikes upon which was
hung cotton impregnated with a composition composed of “vert-de-gris,
vitriol blue and sel ammoniac” (copper acetate, copper sulphate and
ammonium chloride).
Immediately before firing the cotton was soaked with alcohol. Actually
this composition can hardly be considered pyrotechnic; what takes
place is that the alcohol burns, and the flame thus created is
coloured with the copper present in the salts. The whole arrangement
is too cumbersome and involved for modern use, but at the time of its
inception, when colour was practically unknown, no doubt it attracted
great admiration.