It was during the year 1777 that occurred the first attempt to use gunpowder in the shape of a submarine torpedo. This device, which to-day threatens to overturn all established ideas of naval organization and architecture, originated with a clever Connecticut mechanic named David Bushnell. His invention covered not only submarine torpedoes, to be launched against a vessel, but a submarine boat in which an adventurous navigator might undertake to go beneath the hull of a man-of-war, and affix the torpedoes, so that failure should be impossible. This boat in shape was not unlike a turtle. A system of valves, air-pumps, and ballast enabled the operator to ascend or descend in the water at will. A screw-propeller afforded means of propulsion, and phosphorescent gauges and compasses enabled him to steer with some accuracy.
Preliminary tests made with this craft were uniformly successful. After a skilled operator had been obtained, the boat perfectly discharged the duties required of her. But, as is so often the case, when the time for action came she proved inadequate to the emergency. Let her inventor tell the story in his own words:—
"After various attempts to find an operator to my wish, I sent one, who appeared to be more expert than the rest, from New York, to a fifty-gun ship, lying not far from Governor's Island. He went under the ship, and attempted to fix the wooden screw to her bottom, but struck, as he supposes, a bar of iron, which passes from the rudder hinge, and is spiked under the ship's quarter. Had he moved a few inches, which he might have done without rowing, I have no doubt he would have found wood where he might have fixed the screw; or, if the ship were sheathed with copper, he might easily have pierced it. But not being well skilled in the management of the vessel, in attempting to move to another place, he lost the ship. After seeking her in vain for some time, he rowed some distance, and rose to the surface of the water, but found daylight had advanced so far that he durst not renew the attempt. He says that he could easily have fastened the magazine under the stern of the ship above water, as he rowed up to the stern and touched it before he descended. Had he fastened it there, the explosion of a hundred and fifty pounds of powder (the quantity contained in the magazine) must have been fatal to the ship. In his return from the ship to New York, he passed near Governor's Island, and thought he was discovered by the enemy on the island. Being in haste to avoid the danger he feared, he cast off the magazine, as he imagined it retarded him in the swell, which was very considerable. After the magazine had been cast off one hour the time the internal apparatus was set to run, it blew up with great violence.
"Afterwards there were two attempts made in Hudson's River, above the city; but they effected nothing. One of them was by the aforementioned person. In going toward the ship, he lost sight of her, and went a great distance beyond her. When he at length found her, the tide ran so strong, that, as he descended under water, for the ship's bottom, it swept him away. Soon after this, the enemy went up the river, and pursued the boat which had the submarine vessel on board, and sunk it with their shot."
So it appears, that, so far as this submarine vessel was concerned, Bushnell's great invention came to naught. And, indeed, it was but the first of a long line of experiments which have been terribly costly in human life, and which as yet have not been brought to a successful end. In every war there comes forward the inventor with the submarine boat, and he always finds a few brave men ready to risk their lives in the floating coffin. Somewhere in Charleston Harbor to-day lies a submarine boat, enclosing the skeletons of eight men, who went out in it to break the blockade of the port during the civil war. And although there are to-day several types of submarine boat, each of which is claimed to make practicable the navigation of the ocean's depths, yet it is doubtful whether any of them are much safer than Bushnell's primitive "turtle."
But Bushnell's experiments in torpedo warfare were not confined to attempts to destroy hostile vessels by means of his submarine vessel. He made several attacks upon the enemy by means of automatic torpedoes, none of which met with complete success. One of these attacks, made at Philadelphia in December, 1777, furnished the incident upon which is founded the well-known ballad of the "Battle of the Kegs."
It was at a time when the Delaware was filled with British shipping, that Bushnell set adrift upon its swift-flowing tide a number of small kegs, filled with gunpowder, and provided with percussion apparatus, so that contact with any object would explode them. The kegs were started on their voyage at night. But Bushnell had miscalculated the distance they had to travel; so that, instead of reaching the British fleet under cover of darkness, they arrived early in the morning. Great was the wonder of the British sentries, on ship and shore, to see the broad bosom of the river dotted with floating kegs. As the author of the satirical ballad describes it,—
"Twas early day, as poets say,
Just as the sun was rising;
A soldier stood on a log of wood
And saw the sun a-rising.
As in amaze he stood to gaze
(The truth can't be denied, sir),
He spied a score of kegs, or more,
Come floating down the tide, sir.
A sailor, too, in jerkin blue,
The strange appearance viewing,
First d——d his eyes in great surprise,
Then said, 'Some mischief's brewing.'