The General thought it was not necessary for Townsend to give up his business, and so replied from Headquarters at West Point, September 24, 1779:
“Sir, It is not my opinion that Culper Junior should be advised to give up his present employment. I would imagine that with a little industry he will be able to carry on his intelligence with greater security to himself and greater advantages to us, under cover of his usual business, than if he were to dedicate himself wholly to the giving of information. It may afford him opportunities of collecting intelligence that he could not obtain so well in any other manner. It prevents also those suspicions which would become natural should he throw himself out of the line of his present employment. He may rest assured of every proper attention being paid to his services. One thing appears to me deserving of his particular consideration, as it will not only render his communications less exposed to detection, but relieve the fears of such persons as may be entrusted with its conveyance to the second link in the chain, and of course very much facilitate the object we have in view; I mean, that he should occasionally write his information on the blank leaves of a pamphlet, on the first, second, and other pages of a common pocket book, or on the blank leaves at each end of registers, almanacks, or any new publication or book of small value. He should be determined in the choice of these books principally by the goodness of the blank paper, as the ink is not easily legible unless it is on paper of a good quality. Having settled a plan of this kind with his friend, he may forward them without risk of search or the scrutiny of the enemy, as this is chiefly directed against paper made up in the form of letters.
“I would add a further hint on this subject. Even letters may be made more subservient to this communication, than they have yet been. He may write a familiar letter on domestic affairs, or on some little matters of business, to his friend at Setauket or elsewhere, interlining with the stain his secret intelligence, or writing it on the opposite blank side of the letter. But that his friend may know how to distinguish these from letters addressed solely to himself, he may always leave such as contain secret information without date or place (dating it with the stain), or fold them up in a particular manner, which may be concerted between the parties. This last appears to be the best mark of the two, and may be the signal of their being designated for me. The first mentioned mode, however, or that of the books, appears to me the one least liable to detection. I am, &c.
“Go. Washington.”
FOOTNOTES to “GENERAL WASHINGTON’S SPIES”:
[12] This, as related by John Jay and Robert Townsend to James Fenimore Cooper, has been woven into fiction as the basis of the tenth chapter of The Spy.
[13] James Jay, brother of John Jay, claims the credit of this invention. In a letter to Thomas Jefferson he says: “The curious experiments in Sympathetic Inks, fluids with which if one writes on the whitest paper the letters immediately become invisible, are generally known; and so is likewise the facility with which the writing with any one of them may be rendered visible. For this reason I presume the subject has been considered as a matter of mere curiosity and entertainment, and has never been applied to any use in Politics or War. When the affairs of America, previous to the commencement of hostilities, began to wear a serious aspect, and threatened to issue in civil war, it occurred to me that a fluid might possibly be discovered for invisible writing, which would elude the generally known means of detection, and yet could be rendered visible by a suitable counterpart. Sensible of the great advantages, both in a political and military line, which we might derive from such a mode of procuring and transmitting intelligence, I set about the work. After innumerable experiments, I succeeded to my wish. From England I sent to my brother John in New York, considerable quantities of these preparations. He furnished Silas Deane with them when that gentleman first went to France. When Mr. Deane was in Paris, he writ to me in London, requesting further supplies of them, which I accordingly sent him. In the course of the war, General Washington was also furnished with them, and I have letters from him acknowledging their great utility, and requesting further supplies. Gordon in his history of the Revolution relates the fact, but without mentioning the author of the contrivance.
“By means of this mode of conveying intelligence, I transmitted to America the first authentic account which Congress received, of the determination of the British Ministry to reduce the Colonies to unconditional submission; the ministry at the time concealing this design, and holding out conciliatory measures. My method of communication was this: To prevent the suspicion which might arise were I to write to my brother John only, who was a member of Congress, I writ with black ink a short letter to him, and likewise to 1 or 2 other persons of the family, none exceeding 3 or 4 lines in black ink. The residue of the blank paper I filled up, invisibly, with such intelligence and matters as I thought would be useful to the American Cause. All these letters were left open, and sent in that condition to the Director or Secretary of the General Post Office, with a letter insinuating that I thought it could not be the intentions of Government, in their restraining laws, to put a stop to family intercourse; and therefore requesting the party to read over the letters, and if nothing improper appeared in them, that he would permit them to pass in the mail to New York. They passed accordingly, and on their arrival in New York were sent into the American Lines. In this invisible writing I sent to Franklin and Deane, by the mail from London to Paris, a plan of the intended Expedition under Burgoyne from Canada.”
[14] See it on [page 218].
[15] Oakman & Townsend was the firm name, Henry Oakman being the partner at this time, supplying ships and the public with dry-goods and groceries.