During his wanderings he had collected a most valuable professional library, and he now found leisure to devote a good part of his time to study, some of the results of which appeared in the improvements which he carried out on the America. As usual, he also resumed his correspondence. In his letters of this period are many excellent suggestions looking to the welfare and future development of the naval service. Many of these suggestions were subsequently adopted in the service. The following letter, dated August 12, 1782, which he received from John Adams, then minister at The Hague, is pleasant reading: "The command of the America could not have been more judiciously bestowed; and it is with impatience that I wish her at sea, where she will do honour to her name. Nothing gives me so much surprise, or so much regret, as the inattention of my countrymen to their navy; it is a bulwark as essential to us as it is to Great Britain.[38] It is less costly than armies, and more easily removed from one end of the United States to the other. "Rodney's victory has intoxicated Britain again to such a degree that I think there will be no peace for some time. Indeed, if I could see a prospect of half a dozen line of battle ships under the American flag, commanded by Commodore John Paul Jones, engaged with an equal British force, I apprehend the event would be so glorious for the United States, and ay, so sure a foundation for their prosperity, that it would be a rich compensation for a continuance of the war." When Jones heard of the movement which resulted in the surrender of Cornwallis at Yorktown, he had expressed a desire to serve as a volunteer in the army for the campaign under Lafayette. He pined for action always. On this subject he received the following affectionate letter from that gallant Frenchman: "_December 22, 1781_. "I have been honoured with your polite favour, my dear Paul Jones, but before it reached me I was already on board the Alliance, and every minute expecting to put to sea. It would have afforded me great satisfaction to pay my respects to the inhabitants of Portsmouth, and the State in which you are for the present. As to the pleasure to take you by the hand, my dear Paul Jones, you know my affectionate sentiments, and my very great regard for you, so that I need not add anything on that subject.