Looking at Submarines in the 1740s

This is a diagram of a submarine. It appeared in the Gentleman’s Magazine in 1747, illustrating an article titled “Description of a diving ship, built by order of his most serene highness Charles Landgrave of Hesse Cassel.”

The prince reportedly wanted a replica of “the famous diving ship, constructed by [Cornelis] Drebel” in 1620 and demonstrated in the Thames that decade—or at least a ship that did the same thing.

In the 1747 vessel, a man was supposed to fit into the horizontal cylinder marked E with more men in the larger cylinder working a pump. So this submarine was of considerable size. The article described its purpose as “to destroy the enemy’s ships” rather than, say, salvaging wrecks.

That magazine item concluded with this statement:

As to the difficulty of breathing in such a ship, Drebel mentions that he had provided a certain quintessence of air, one drop of which emitted would render the vitiated air again fit for respiration, but Dr [Denis] Papin imagines this is rather a thing to be wish’d than a reality.

Two years later the Gentleman’s Magazine published another picture of another submarine.

Although the accompanying article signed “T.M.” credited the picture and description to “M. Marriott,” it had actually been designed by Giovanni Alfonso Borelli in 1678. This cutaway view focused on the leather bellows that Borelli imagined being used to take in and expel water for ballast.

The second article prompted letters from Samuel Ley and John Lethbridge discussing submarines they had seen, read about, or developed themselves. There was some squabbling over credit.

Historians of the submarine presume that David Bushnell studied these pictures in the Gentleman’s Magazine as he developed his idea for a submarine as a Yale College student in the early 1770s, though he never mentioned such influence.

The magazine articles show how in the seventeenth and eighteenth centuries many European scientists were working on diving vessels, and people saw their military potential. At the same time, these diagrams show how inventive Bushnell was. His small Turtle didn’t look like either of these plans. It had some similarities to the one-person diving machine that Lethbridge described making, but even more significant differences. And Bushnell’s submarine actually worked.