Frézier (1747) makes the following prefatory remarks to his chapter on shells:
“The name of ‘balon’ is given to a firework which is thrown into the air like artillery bombs for war, so that they are often given the same name as bomb.
“The difference between this firework and a bomb is not only that the former is to amuse and that the latter to destroy, and that the one is made of iron, and the other of wood, linen, or cardboard, but principally because the latter is made to burst and throw out its garniture at the point of the highest elevation, while the war bombs do so at the moment of their fall to the earth, also the war bombs are thrown towards the horizon, while the firework bombs are thrown vertically or nearly so.
“The fireworks differ also from the war bombs in shape, the former being not always spherical, as the latter are.
“We must therefore understand by the name of shell a firework of which the effect and principal beauty is that while going up in the air it only shews a small stream of fire, which multiplies itself suddenly into a great number of others at the moment of its highest elevation, which causes a pleasant surprise.
“As this firework does not lift itself, but is thrown by impulsion the same way as a bomb, it can, like the latter, only be fired from a mortar.”
He describes two shapes of shell, the spherical and cylindrical, with a hemispherical end, which shape is more convenient where the contents are long in form, as rockets, Roman candles, etc. He attributes the introduction of this shape to Siemienowitz, who, he says, made the cases of wood. He himself, however, adopts the modern method, as he does with the fuse, which he calls the port-fire. The lifting charge, however, is placed in the mortar separately from the shell and ignited at a touch-hole, in which, as will be seen, he differs from modern practice.
He gives a list of garnitures or fillings, which are interesting as showing the practice of the day:
“The first is the one which gives the effect of a waterfall or head of hair. This is made of thin narrow tubes, or if possible, of thin canes, cut to the length of the shell, and filled with a slow-burning composition made of three parts of priming powder, two of charcoal, and one of sulphur, damped with a little petroleum, and capped with a paste made of powder crushed in distilled water or spirit and afterwards dried. All these are put in the tube, around the one which is used for the passage of the port-fire.
“When it is full the loaded port-fire is introduced, and pushed so far that it reaches the frame, and when it is touching the lid, this lid must be glued by the rough ends to that of the tube, and the shell is finished.
“As it is rather heavy, it is advisable to adopt means for its resisting the shock of the lifting charge of powder which drives it out of the mortar, by strengthening it with a covering of linen strips, which should be stuck on to the shell by means of a paste, composed of two-thirds of flour paste, and one-third of glue.
“Unless this is done it often happens that the shell bursts before it rises in the air.”
The second consists of serpents, the third of “saucissons volans,” similar to the “fiz-gig” of Bate; the choke in the middle between the composition and the bang being varied in position so as to produce a succession of bangs. The vacant spaces left over in the shorter may be filled with stars.
The fourth is of stars arranged in beds of grain powder; the interstices being filled with a mixture of mealed powder and charcoal. The fifth of “light balls,” and for the sixth he describes “the manner of making figures and various shapes in fire appear in the air.” These letters are made on a frame covered with composition, and are consequently limited to a size to the internal diameter of the shell, that is, less than eight inches. It seems improbable that they could be distinguished satisfactorily at the height of a shell’s trajectory, besides which the difficulties involved, as he himself explains, are very great, which no doubt explains the fact that this idea is now obsolete.
Under the heading “Double and Triple Balloons,” this writer describes the method of placing shell of smaller size inside a larger. The bursting of the first shell lights the short-time fuse of the contained shell, which falls some distance and bursts. With the triple shell this action is repeated.
Jones (1765) divides shell into four kinds, namely, “illuminated balloons” filled with stars; “balloons of serpents,” “balloons of reports, marrons and crackers,” and “compound balloons.” The last description is misleading, as the balloon is not compound but the contents are varied, as for example, the contents of one specified ten crackers of six reports, twenty golden rains, sixteen two-ounce cases charged half-inch with star composition and bounced, two ounces each of brilliant, blue, coloured tailed, large string and rolled stars. It is hard to believe that this writer had ever seen a shell fired in this manner, the result would have been mere confusion. The star compositions of that date were very rudimentary, the colours when seen from the distance of a bursting shell were indistinguishable.
One interesting detail in Jones’s work is the classification of sizes. The smallest shell mentioned by him is the “Coehorn Balloon”; he does not give the size, but it is given in the “Military Encyclopedia” as 4⅔ inches. This corresponds to the 4½-inch of to-day. The name was apparently derived from a Dutch military engineer of that name. The next size is the royal 5½-inch, and above that 8-inch and 10-inch.