The first reference to the use of his submarine by America appears in his letter to Lord Castlereagh, dated “London December 13th, 1805,” given on pages 104–8. When this letter was written, it was becoming clear to Fulton that the British Government might refuse to make payment under the contract, and that he would have to use some sort of force to compel a compliance with the terms. The only force that he could employ would be a threat to give his secret to some other power. France was now quite out of the question, and there was no one power in Europe that could serve as a means to scare. The United States, now become a nation, was the only hope. In his letter to Lord Castlereagh he advances the ingenious solution that he receive a substantial cash payment and an annuity, the latter to continue only so long as the secret was kept inviolate by him. He concludes by diplomatically hinting that the only government to whom he would be likely to explain his invention would be his own. In the paper that he read to the Arbitrators he makes a distinct threat that, unless a satisfactory offer be made, he will not only give his secret to America but publish it to the whole world, although he modified this by stating that he had “no desire to introduce my Engines into practice for the benefit of any other Nation.” (page 126.) Although refused by the Arbitrators, he made a final effort with Lord Grenville, on September 3rd, to obtain his pecuniary award, by again offering what he called his “neutrality.” (pages 137–8.) But the best exposition of Fulton’s position is given by himself in the concluding pages of his Notes, this part being written after his letters to and audience of Lord Grenville on September 3rd. This quotation was his final word: “I have now said sufficient of this System to enable any ingenious man to make and arrange the Engines and any maritime nation to carry the whole into effect. If I live it is my intention to give this system to the public engraved with every necessary detail and I have made these sketches and this loose description which is litte more than a sketch of my studies on this Subject. In order that they may not be lost to my country and mankind in case of any accident to me.