Most of the inventions in pyrotechny, at this period, were of a futile sort, more especially by reason of the fact, to which attention has already been called, that subsequent improvements in ordnance and explosives rendered them essentially useless.
But such a criticism does not apply to the rocket light ball, which was the most important invention of Sir William Congreve. This was not only valuable in the age of its inventor, but the principle of its construction has been applied with advantage in our own day.
The contrivance was a rocket, which, on reaching the extreme altitude of its ascent, discharged a species of light ball that thereafter remained suspended in the air by means of a small parachute, to which it was attached by a chain. "Thus," as a contemporary author writes, "in lieu of the transient momentary gleam obtained by the flaring out of the ordinary light ball, a permanent and brilliant light is obtained, and suspended in the air for five minutes at least, so as to afford time and light sufficient to observe the motions of the enemy, either on shore or at sea. It should be noted that nothing in any way equaling the effect of this light ball can be obtained by any projectile force, from either guns or mortars, for the reason that the explosive charge of the piece must certainly destroy any construction of a sort to produce such a suspension in the air."
From the limitations of knowledge possessed by this writer, he was amply justified in such high praise for the rocket light ball and in the contention that it could not be equaled by any projectile from ordnance. He could not guess at those developments which have resulted in the rifle light of to-day. As a matter of fact, the cartridge containing such a light is discharged from a rifle without injuring in the slightest degree the mechanism of the parachute attachment. 66
But, too, we must give credit to this invention for the practical use of the parachute in sustaining a flare. Indeed, in the century that has elapsed, we have been unable to increase appreciably the time limit for the burning of such a light, although we have greatly increased the brilliancy of the illumination.
A primitive strategy was the unexpected lighting of a fire by the besieged, with the result that a foe advancing to assault under cover of darkness would be plainly revealed, and thus thrown into confusion. Originally, simply a pile of brush, quickly kindled, sufficed for the purpose. As the nature of various combustibles became known, improvements were made by using suitable compositions that would burn fiercely and cast a brilliant light. A final development came when such materials were compressed into projectile form and thrown to a distance, either by hand or by ordnance, or, as in the case of Congreve's rocket light ball, by their own power. Such flaming missiles were employed also for incendiary purposes, and out of them grew the almost innumerable varieties of incendiary bombs, which were widely utilized in military operations, under many different names. They were of service especially in besieging towns and in naval actions. The prime essential was always that the construction should be of such a sort that the composition would continue to burn even while in contact with water. One of the simplest devices was of rope, which, after being duly soaked in a combustible liquid mixture, was rolled into a ball, and then inclosed in a sack, to be fired from a mortar. This device was invented by a French officer during the siege of Toulon.
The incendiary bomb was modified so as to include in its effects not only the causing of fire, but also the wounding and slaying of enemy troops. For this purpose the containers of the combustible were fashioned of metal in varying forms, so that their contact would work injury. Often shells were made by uniting two hollow hemispheres, which were duly provided with bores and a fuse. These projectiles were exploited under the name of "murdering marrons."
To us, to-day, some of the methods that were popular a few generations ago seem almost unbelievably clumsy. Yet, simple as they were, they sometimes proved that their efficiency was adequate to the conditions under which they were utilized. Our familiarity with the horrible ingenuity and intensity of explosives crashing from hidden mines is likely to create in us a mood of rather pitying contempt for the primitive attempts of our ancestors in this direction. But it would be unjust to condemn methods that were, in fact, well adapted to the needs of the time.
As an illustration of such former methods, we may consider one of the most pretentious, which was announced by a French publication, in 1815, under the name of the "the pyrophore of defense."
According to the author's description, this device might be constructed and set in readiness for use within a period of 24 hours, and was available for the defense of towns, roads, passages, and defiles. The pyrophore was made up of a square box with a lid, and was commonly large enough to contain 50 pounds of gunpowder. The lid was furnished with crosspieces, by which it might be opened when necessary. Rings were fastened to the sides of the box. These were of iron, very strongly fixed in position by means of bolts, which penetrated the sides and were clenched. Either ropes or chains were fastened to the rings, with crotchets at the ends. These were designed to run on two fixed pulleys, which could be stationed wherever desired. A common position for the pulleys was at the two extremes of a battery, where they might be managed by artillerists. It was usual to have a bar or grate set at the point where it was intended to place the pyrophore. It was then lowered from under cover into the required position, by means of the pulleys. The interior of the contrivance was so disposed that, on raising the lid, the powder would fall into a funnel-shaped gutter, at the end of which the match could be applied.
It is hardly necessary to point out that this machine was of a cumbersome sort, and could rarely be used to advantage, by reason both of the time required for its construction and the difficulties in the way of its operation.
Nevertheless, it appears from contemporaneous accounts that successful results were sometimes obtained by use of the device. It was especially available in defense against an attacking enemy on occasions when it could be exploded by the defenders from cover.
Fire pots were very frequently employed in the early military operations of the nineteenth century. They were an important part of the equipment for ramparts in time of siege. The pots employed for this purpose were of any ordinary ware and of diverse shapes. They were furnished with grain powder, and charged sometimes also with firestone. After being filled with the proper ingredients, the pots were covered over with parchment. The match passed through an opening in the top, to be kindled when desired by a port fire.
In some instances, the fire pot was provided with an iron hoop and hook by which it might be lifted. This form was often used for service at sea, as a means of defense against attack by small boats. For that purpose, the pots were hung over the side of the vessel in such position as to come readily into contact with the approaching boats. They were thus capable of offering effective defense. One account tells of a vessel in the Indian seas that owed to the use of fire pots its rescue from an onslaught by pirates. It was found that flight would not avail for the ship's escape from the enemy. The captain thereupon set the crew to making fire pots for defense, since the foe had them hopelessly outnumbered. The pirates approached the vessel in ignorance of the danger that menaced them. As they crowded against the sides, about to swarm on deck, the fire pots were exploded - with such effect that the enemy was thrown into confusion from which it could not recover, and the ship pursued its way in safety.
A form of firework commonly employed for exhibition purposes gave to military inventors the suggestion for a particular kind of incendiary fire pot. The vessel, in this case, was made of copper, so that it possessed great strength. Pieces of firestone were rolled in a paste of meal powder and brandy. After a charge of powder had been placed in the pot, with a quick match inserted, the fragments of firestone were thrown on top. The match itself was made sufficiently long to extend out over the brim and hang down the side.
Another curious weapon was called the inflammable dart. In the construction of this an ordinary rocket case, having an exterior diameter of one inch, was charged solidly with the usual explosive composition. Sometimes, however, a variation was made by adding one spoonful of earth to three spoonfuls of the composition. The case was duly pierced, and a quick match fixed at the end for setting it off. The dart itself was made of iron, with a very sharp point and edges. It was firmly fastened to the head of the case. With the addition of the usual stick lashed to the case, the inflammable dart was complete. Its advocates praised it especially for the readiness with which it might be sent in any desired direction from under cover. From the current accounts, however, it appears that the only practical efficiency of the weapon was in defense of buildings during assault by an enemy.
The name firebrand was given to a contrivance first developed by the French, and called by them the loupe-feu. This was an incendiary weapon of such simplicity as to possess some merit on that account, if on no other. It was merely a long stick, into one end of which were set two iron prongs. These were wound about with a thick rope, which had been soaked in a liquid explosive. In effect, the loupe-feu was a convenient instrument for quick setting of fires.
Fire flasks were widely employed, chiefly owing to the ease with which they might be prepared. They were formed from any bottle, into which a charge of grain powder, mixed with firestone, was introduced and compressed with a stick: A cloth was then drawn about the bottle as a cover, over which was laid a coating of. pitch. The cloth, in turn, was secured by parchment. The explosion was effected by means of a match passing down within the neck of the bottle.
It is interesting to compare this primitive device, which was thrown by hand, with the modern ingenious and highly destructive hand grenades so commonly used in the World War.