A Machine to Blow Up Shipping?

Yesterday I quoted Continental artillery colonel Jeduthan Baldwin’s record that on 14 Dec 1775 he “went in the afternoon to Dotchester point to See the mashine to blow up Shiping, but as it was not finished, it was not put into the water.”

It sure sounds like Baldwin really saw an unfinished machine which was eventually supposed to go into the water. Which puts me in mind of the pioneering submarine of David Bushnell, who had just graduated from Yale at the advanced age of thirty-five. Bushnell was working on his machine by August 1775, when a friend described it in a letter to Benjamin Franklin. On 23 Oct 1775, Samuel Osgood, aide de camp to Gen. Artemas Ward, wrote to John Adams from the camp at Roxbury:

The famous Water Machine from Connecticutt is every Day expected in Camp; it must unavoidably be a clumsy Business, as its Weight is about a Tun. I wish it might succeed [and] the Ships be blown up beyond the Attraction of the Earth, for it is the only Way or Chance they have of reaching St Peter’s Gate.

By the next month, a British spy named James Brattle, working as a servant of Continental Congress delegate James Duane, had sent the same news to Gov. William Tryon of New York.

However, as of 7 December Bushnell was still testing his craft on the Connecticut River, wrestling with a peculiar problem of submarine warfare: it’s dark inside a waterproof chamber, and lighting a candle uses up the oxygen supply. Bushnell, with Franklin’s advice, planned to use some bioluminescent plant materials, but they weren’t available in late fall.

Bushnell formally presented his submarine plan to the Connecticut Council in February 1776. At that time he planned to move it to Boston to engage the Royal Navy there, but the British evacuated the next month, making that trip unnecessary. The vessel, dubbed the Turtle, finally saw action on 6 Sept 1776 in New York harbor, the first submarine attack in naval history. (The picture above comes from Digital History at the University of Houston.) I haven’t come across any indication that a version of Bushnell’s machine was in Dorchester the previous December.

The machine that Baldwin saw might therefore have been another invention. There was at least one other grand scheme to attack the British fleet that fall. On 20 Oct 1775, John Hancock signed a letter drafted by a Congressional committee to Gen. George Washington:

Captain John Macpherson having informed the Congress that he had invented a method by which, with their leave, he would take or destroy every Ministerial armed vessel in North-America, [a committee of delegates] reported that the scheme, in theory, appeared practicable; and that, though its success could not be relied on without experiment, they thought it well worth attempting on the fleet in and about Boston Harbour, their destruction being an object of the utmost importance.

The Congress have therefore desired Captain Macpherson to repair immediately to Cambridge. They recommend this matter to your particular attention...

Macpherson was a Scotsman with experience in the Royal Navy who had settled in Philadelphia. His son, also named John, was an aide to Gen. Richard Montgomery in the American invasion of Canada; both men would die outside Québec at the end of the year.

On 8 Nov 1775, Washington replied that he wasn’t as optimistic about the captain’s plan as the captain was:

I laid myself under a solemn tye of secrecy to Captn. McPherson, and proceeded to examine his Plan for the destruction of the Fleet in the Harbour of Boston, with all that care and attention which the Importance of it deserved, and my Judgement could lead to: but not being happy enough to coincide in Opinion with that Gentleman, and finding that his Scheme would Involve greater expence, than (under my Doubts of its success), I thought myself justified in giving into, I prevaild upon him to communicate his plan to three Gentlemen of the Artillery (in this Army) well acquainted in the knowledge, and practice of gunnery; by them he has been convinced, that in as much as he set out upon wrong principles, the Scheme would prove abortive.

unwilling however to relinquish his favourite project of reducing the Naval force of Great Britain, he is very desirous of building a number of Row-Gallies for this purpose; but as the Congress alone are competent to the adoption of this measure, I have advised him (altho’ he offered to go on with the building of them at his own expence ’till the Congress should decide) to repair immediately to Philadelphia with his proposals; where, if they should be agreed to, or Vessels of Superior force, agreeable to the Wishes of most others, should be resolved on, he might set instantly about them, with all the materials upon the Spot; here they are to collect; to him therefore I refer for further information on this Head.

Capt. Macpherson carried this letter and others back to Philadelphia for the commander-in-chief. He could have returned to Boston by December, but I have no evidence that he did.

So what was the machine that Baldwin expected to see in use in December 1775? It might have been a prototype of Bushnell’s, or another of Capt. Macpherson’s ideas, or yet another machine created by someone else entirely. In any event, it didn’t work.