- Historic Sites
1. The Connecticut Water Machine Versus The Royal Navy
December 1980 | Volume 32, Issue 1
Shortly after a midnight in early September of 1776, a strange little convoy set out from South Ferry Landing at the southern tip of beleaguered Manhattan Island on a mission unique in Revolutionary War history, indeed, in world history. Two whaleboats towed between them an odd craft which, riding nearly awash, carried a crew of one—a young sergeant of the Connecticut Militia. To the rasp of oars in thole pins, the tow headed south toward Staten Island and The Narrows, nearly five miles distant, where a host of lights marked a British armada riding serenely at anchor.
Without any naval opposition, these ships ranged the East and Hudson rivers, greatly increasing General Howe’s mobility as he tightened the noose around the Continental Army, now isolated on Manhattan foDowing the defeat on Long Island. From Brooklyn to Hell Gate, the British were poising for a strike across the East River. An American victory, however small, was sorely needed to boost morale. The man who hoped to engineer this victory—a slightly built, somberly clad civilian—paced anxiously at South Ferry Landing as the little convoy slid off into the night.
In less than an hour, the stern lanthorns on the nearest ships were clearly visible, even the faint golden wakes they cast on the water. The rowers rested on their oars while the sergeant drifted up between his escorts. After a brief, murmured exchange, the towlines were cast off and the whaleboats turned back toward Manhattan. Now drifting alone, the sergeant prepared to move the Connecticut Water Machine against the British.
The evolution of the sergeant’s strange craft literally began with a bang when, in 1772, David Bushnell, a brilliant mathematics student at Yale, successfully exploded two ounces of gunpowder in a submerged wooden pipe “to prove to some of the first personages in Connecticut that powder would take fire under water.” His experiment was revolutionary for, although marine petards had been devised over a century before, they were surface craft with gunpowder cargo, intended to damage ships at or above the waterline. Bushnell later demonstrated the destructive force of underwater explosion by placing two pounds of gunpowder in a wooden bottle that was piped upward through a two-inch oak plank surmounted by a hogshead stone-weighted to sink nearly awash. “A match put to the priming exploded the powder,” the inventor reported, “rending the plank … demolishing the hogshead, and casting the stones and the ruins … with a body of water, many feet into the air, to the astonishment of the spectators.”
Born to a struggling farm family near Saybrook, Connecticut, David Bushnell was twenty-eight years old before settlement of his modest inheritance permitted him to enter college. A fervent Whig, he participated in the campus movement for colonists’ rights and numbered Nathan Hale among his friends. Sensing military application of his experiments should war come, he had, by 1774, begun to draft plans for a “submarine mine, or torpedo.”
A stout log was to be hewn to an egg shape, then sliced longitudinally, the two halves being hollowed out to accommodate 150 pounds of gunpowder and the detonator—a clockwork that would trigger a flintlock after a preset interval of up to eight hours. Bound together by iron hoops, the completed “egg” would then be waterproofed by tarring.
Satisfied that this mine would sink any ship afloat, Bushnell next pondered how to attach it to a target’s hull. Going alongside an enemy ship by small boat, even at night, was risky. Furthermore, for maximum concussive effect, the mine should explode below the waterline. Ideally, then, the target should be approached, and the mine affixed, underwater. Intrigued, he began to ponder the practicality of this novel proposition.
The concept of a submarine did not spring full-blown from David Bushnell, for man had been intrigued by the idea of underwater craft for nearly two centuries. In 1575 a British naval officer named William Bourne designed, but never built, a boat with a wooden framework raised above the gunwales and covered with waterproofed leather. To submerge, the vessel’s volume was to be decreased by tightening hand vises that contracted the leather covering, while to ascend, volume was restored to normal by relaxing the vises. Such a boat was in fact launched in 1605 and promptly lost when the restored buoyancy of the leather was not enough to break the suction of the muddy river bottom. The first moderately successful underwater craft—that of the Dutch physician Cornells Drebbel- resembled its predecessor, with oars protruding through waterproof leather flaps for propulsion. In 1620 it submerged fifteen feet in the Thames River, maneuvered, and returned to the surface.
To what extent Bushnell was acquainted with any of these earlier designs is unknown. But it was he alone that first made the submarine a practical reality and a potential naval weapon.
By winter vacation, 1774, his efforts had begun to coalesce into plans for an underwater mine-delivery vehicle, or “Sub-Marine Vessel,” as he termed it. And with the start of war at Lexington and Concord on April 19,1775, he hurried back to Saybrook, eager to complete these plans now that enemy hulls were no longer a theoretical abstraction.
To avoid gossip reaching the British, Bushnell had his submarine built in a shed on secluded Poverty Island in the Connecticut River, not far from Saybrook. He bruited it about that he was going into fishing and that the shed would serve as a small boatyard. Thus, no suspicions were aroused as the strange craft began to take shape.