In the dead of night on 7 September 1776, 238 years ago this Sunday, a strange semi-submerged vessel made its way out into New York Harbor. The mission of the tiny American submersible, named Turtle: send the massive 64-gun British ship-of-the-line HMS Eagle to the bottom. In his Military Journal of the American Revolution, published in 1862, James Thacher describes the submarine and her single foray into combat.

“By some gentlemen from head-quarters, near New York, we are amused with an account of a singular machine, invented by a Mr. D. Bushnell of Connecticut, for the purpose of destroying the British shipping by explosion. This novel machine was so ingeniously constructed, that, on examination, Major-General Putnam was decidedly of [the] opinion that its operations might be attended with the desired success; accordingly he encouraged the inventor, and resolved to be himself a spectator of the experiment on the British shipping in New York harbor.

“Mr. Bushnell gave to his machine the name of American Turtle or Torpedo. It was constructed on the principles of submarine navigation, and on trial it has been ascertained that it might be rowed horizontally, at any given depth under water, and the adventurer, concealed within, might rise or sink, as occasion requires. A magazine of powder was attached to it in such a manner as to be screwed into the bottom of the ship; and being now disengaged from the machine, the operator retires in safety, leaving the internal clock work in motion; and at the distance of half an hour, or an hour, the striking of a gun lock communicates fire to the powder, and the explosion takes place.

“It was determined to make the experiment with this machine in the night, on the ship Eagle, of sixty-four guns on board of which admiral Lord Howe commanded. General Putnam placed himself on the wharf to witness the result. Mr. Bushnell had instructed his brother in the management of the Torpedo with perfect dexterity; but being taken sick, a sergeant of a Connecticut regiment [Ezra Lee] was selected for the business, who, for want of time, could not be properly instructed. He, however, succeeded so far as to arrive in safety with his apparatus under the bottom of the ship, when the screw, designed to perforate the copper sheathing, unfortunately struck against an iron plate, near the rudder, which, with the strong current and want of skill in the operator, frustrated the enterprise; and, as day-light had begun to appear, the sergeant abandoned his magazine, and returned in the Torpedo to the shore.

“In less than half an hour a terrible explosion from the magazine took place, and threw into the air a prodigious column of water, resembling a great water-spout, attended with a report like thunder. General Putnam and others, who waited with great anxiety for the result, were exceedingly amused with the astonishment and alarm which this secret explosion occasioned on board of the ship. This failure, it is confidently asserted, is not to be attributed to any defect in the principles of this wonderful machine; as it is allowed to be admirably calculated to execute destruction among the shipping.”

Despite Thacher’s dismissive tone and the mission’s lack of success, Turtle proved that the submarine could be a viable instrument of war, one which could strike decisively and, perhaps more importantly, in secret. It is amazing to think that just over 175 years later the Navy would commission USS NAUTILUS (SSN-571), hundreds of times bigger than Turtle and powered by a fuel source which would have seemed nothing short of magical to Revolutionary-era Americans.