The experiments with rockets early extended adaptations of them for use at sea. Their value was, of course, speedily recognized for signal purposes in naval warfare, and also especially for indicating distress to those on shore, in the hope of rescue. This most important use of signal rockets has continued, and has grown steadily during more than 100 years, until to-day every ship is fully equipped with the necessary supplies of rockets for signal purposes.

One variety of the rocket, to be used in case of distress at sea, was first developed fully a century ago. It was called the succoring or marine rocket. This was made sufficiently large to carry aloft a small cord, designed to serve as a first means of establishing communications between ship and shore. The original form of the rocket was described as having an interior diameter of at least 2 inches. An essential difference was displayed in the size of the attached rod for directing the flight. This was reduced by one-half in both length and thickness, to the dimensions usual for a rocket of one-half the caliber. One end of the fine cord was fastened to the rod. Care was taken in coiling the cord to arrange it so loosely that it would offer the least possible resistance on being drawn upward by the rocket's flight.

Advocates of the succoring rocket pointed out that, in addition to its availability for establishing communication with the shore, it could also be employed to advantage in the case of a seaman falling overboard at sea, since by means of it a line could be cast to him immediately, even from a considerable distance.

The device of a shell with cord attached was invented by a Mr. Bell. This shell was to be fired from a mortar on the deck of the ship, thus carrying the line to those on shore, for the purpose of rescue. His contrivance underwent the tests of a practical demonstration, with such satisfactory results that a reward of 100 guineas was bestowed upon him by the British Government for his invention.

A Mr. Holton was responsible for a somewhat similar device, with the same end in view. But, in his contrivance, instead of a shell, a harpoon served as the projectile with rope attached. The harpoon was thrown from a long gun. It was equipped with lateral points, so that it would hold fast to any object with which it came in contact. This construction made it a possible agent, not only for life-saving, but for warfare, to be cast against an enemy ship. Mention of this use is made by the inventor in his description, but he failed to explain in detail any specific value to accrue from such a form of attack.

The ingenious Congreve exercised his facility in invention by adapting his rocket with parachute attachment to use at sea as an incendiary weapon. The advantage of his device lay in the fact that it was capable of taking effect at a distance greatly beyond the range of any other projectile known at that time. It had, too, the added merits of being cheap, simple, and easily portable.

The floating carcasse, as Congreve named this firework, was constructed generally on the pattern of the light ball. The rocket in its flight carried up with it the fire ball, to be set burning and cast forth at the end of the flight. By means of a parachute, the ball remained supported in the air. Thus far, the floating carcasse followed exactly Congreve's earlier invention. Its distinctive feature lay in the fact that it was now to be carried in still further flight by a natural agency - wind. Its effectiveness was dependent, in the first instance, on the duration of burning time for the ball, And, in the second instance, on the degree of nicety with which the flight was adjusted to the prevailing breeze. The floating carcasse was intended to be thrown in large quantities from a blockading squadron, when, with a favoring wind, it might be borne against the enemy's fleet, or an arsenal on shore, with great possibilities of destruction as an incendiary weapon.

One contention in behalf of the effectiveness of this floating carcasse was based on the fact that it was not necessarily visible in its flight by night, since it might be constructed in such fashion as to burst into flame only after it had settied. Thus, it might work havoc by lodging, unperceived, in the rigging of floatillas, or on the roofs of buildings ashore, when all ordinary means of approach were barred.

The French conceived the idea of a firework to which, from its purpose, they gave the name trompe-route. This was an invention intended to deceive the enemy as to the course of a vessel at sea. It was constructed after the manner of an ordinary fire lance, having a length of 12 inches and a diameter of 1 inch. This was fixed in the center of a round piece of plank. When the device was to be used, it was only necessary to set the lance alight, and then to lower it on its plank to the water. It was cast free to float according to the direction of wind and tide. In connection with the use of the trompe-route, the vessel from which it was sent was darkened, so that it sailed with no light showing. It was expected that the watching enemy would take the burning trompe-route for the light of a ship, and so follow it, while the ship itself escaped in the darkness.

It is interesting to contrast this simple device with the elaboration of a somewhat similar purpose to-day in the use of smoke screens, by which the movements of vessels are concealed from enemy observers.

Consideration of naval variations in pyrotechny requires a brief attention to fire ships, which have been persistently employed through the centuries in warfare at sea.

Ships designed to serve as incendiary agents are generally selected, with a view to economy, from the old vessels available. These are filled with combustibles, and are also fitted, when possible, with grappling irons in order to hook fast to the craft of the enemy. In the use of fire ships on rivers, careful calculation of the direction of the currents is necessary, in order to insure successful movement of the incendiary boats against those of the enemy. In like manner, at sea, wind and tide must be regarded, in order to win a favorable issue of the exploit.

Old records tell how seamen of Tyre employed fire ships against Alexander. The Crusaders, also, made use of them in their operations at Acre. At the siege of Antwerp, in 1585, the Spaniards suffered severely from the ravages of fire ships. While the Duke of Parma was endeavoring to throw a bridge over the Scheldt, Gianibelli sent against the structure a fleet of vessels loaded with combustibles, so prepared that they exploded on reaching their objective.

Three years later, Lord Howard of Effingham made use of fire ships, with extraordinary success, against the Spanish Armada. The credit for this operation also should go to Gianibelli, since it was by his advice that Lord Howard undertook the exploit.

The Greeks have maintained their original supremacy in the use of fire as a war instrument by frequent victories against their constant enemies, the Turks, through the use of fire ships.

But a survey of the historical facts does not justify an impression that fire ships are uniformly employed to advantage. It would seem, indeed, that they, like every other form of combat, are dependent on the courage and resourcefulness of their users for the measure of their achievement. Often, their failure is of such a singularly complete character as to be explicable only by the crass stupidity of those sending them forth. Thus, in 1857, during the war between British and Chinese, the Orientals set adrift whole fleets of fire vessels against the warships of the British, but no slightest damage was effected.