Robert Fulton and the Submarine

by William Barclay Parsons

First

To construct one or two Good Plunging Boats each 36 feet long and 12 feet wide Boats of this capacity would be Sufficient to contain 8 Men and Air for 8 hours. With Provisions for (paper is torn here) and transport from 25 to 30 Bombs at a time, their Cylenders Should be Brass and of a Strength to admit of descending 60 or 80 feet under Water in case of need And they may be Constructed to Sail from 5 to 7 Miles per hour; here it may be well too proove that Quick Sailing is not one of the most important considerations in this invention, if such a boat is Pursued, She plunges under water and as She Can remain under Water from 4 to 8 hours and Make at least one Mile Per hour She Could rise Several miles from the Place where She Plunged to renew her air, thus the enemies Ports could be approached, And particularly under the cover of the Night Nor do I at Present See that any Possible Vigilence could Prevent these invisible engines entering their Ports and Returning at Pleasure—

Second

Let there also be Some hundreds of Bombs Submarine Constructed of Which there Are two Sorts one arranged with Clockwork in Such a manner as to Go off at any Given Period from 4 Minuets to 4 hours, the Other with a gun Lock as before mentioned So as to go off when it Strikes against a Vessel or when a Vessel runs Against it. Each of these carcasses is arranged So as to float from 4 to 15 feet under water in Proportion to the Water which the Vessels to be attacked Draws, And in this there are two advantages, the first is that the bomb is Invisible, the Second is that when the explosion takes place under water the Pressure of the colume of water to be removed forces the whole action of the powder Against the Vessel; it was the resistance of the water which caused the Sloop on which I proved the experiment to be reduced to Atoms; for Water when Struck Quick such as the Stroke of a cannon ball or the expansion of Powder acts like a Solid, and hence the whole force was Spent on the Sloop or rather passed through the Sloop in finding its Passage to the air by the perpendicular and Shortest line of Resistance—the Same effect would no doubt be produced on a Vessel of Any dimensions by applying a Proportionate Quantity of powder Such as 2, 3 or 4 hundred Weight,

Therefore being prepared with plunging boats and Bombs submarine let the business of the boats be to go with cargoes of bombs and let them loos withe the current into the harbours of Portsmouth, Plymouth, Torbey or elsewhere, those with their graplings floating under water could not be perceived Some would hook in the cables, bow or Stern, or touch in their Passage; many no doubt would miss but Some would hit go off and destroy the Vessels they touched, one or more Vessels Destroyed in a Port by such invisible agents would render it to dangerous to Admit of any Vessel remaining. And thus the enemy may At all times be attacked in their own Ports—and by a means at once cheap, Simple And I conceive certain in its operation. Another mode Should be to go with cargoes of Bombs and Anchor them in the entrance of rivers So as to cut off or Blockade the commerce 2 or 3 hundred for example Anchored in the Thames or the channels leading to the Thames would completely destroy the commerce of that river and Reduce London and the Cabinet of St. Jameses to any tirms; no Pilot could Steer clear of Such hidden dangers, no one dare to raise them even if hooked by graplings as they could not tell the moment they Might touch the Secret Spring which would cause the explosion and destruction of everything Around them. No Vessel could Pass without the utmost danger of running on one of them And her instant destruction, if this measure Should ever become necessary Some Vessels Will most certainly be destroyed and their Destruction alarm the whole commerce of the Thames, by this means the Thames may be blockaded and the trade of London completely stoped nor can the combined fleets of England prevent this Kind of attack—And this is Perhaps the most Simple and certain means of convincing England that Science can put her her in the Power of France and of compelling her to become a humble Pleader for the liberty of the Seas She now denies to her Neighbors—I therefore conceive that it will be good Policy to commence as Soon as Possible the construction of the Boats and bombs if they can be finished before the arrival of Peace their effects may be Proved during this War Should Peace be concluded before they are finished the experiments can be continued Men can be exersised in the use of the engines; And it is Probable in a few years England will See it her best policy never to give france reason to exersise this invention against her—if England cannot prevent the Blockade of the Thames by the means of plunging boats and Bombs submarine, of what use will be her boasted navy, the free Navigation of the Thames nourishes the immense commerce of London And the commerce of London is the Nerves and Vitals of the Cabinet of St. Jameses—convince England that you have the means of Stopping that Source of Riches—And She must Submit to your terms—

Thus Citizens I have presented you with a Short account of my experiments and Plan for using this invention Against the enemy, hoping that under your protection it will be carried to Perfection, and Practised to promote the Liberty of the Seas—

Health and Sincere Respect

Robert Fulton

After reading the above, the commissioners desired further information which Fulton gave in the following letter:

Complimentary day an 9