A paper on "The Commerce of Louisiana," bearing date the 18th of April, 1798, is found in the Office of State, supposed to have been communicated by Mr. Daniel Clark, of New Orleans, then a subject of Spain, and now of the House of Representatives of the United States, stating certain commercial transactions of General Wilkinson in New Orleans. An extract from this is now communicated, because it contains facts which may have some bearing on the questions relating to him. The destruction of the War Office by fire in the close of 1800 involved all information it contained at that date. The papers already described therefore constitute the whole of the information on the subjects deposited in the public offices during the preceding Administrations, as far as has yet been found; but it can not be affirmed that there may be no other, because, the papers of the office being filed for the most part alphabetically, unless aided by the suggestion of any particular name which may have given such information, nothing short of a careful examination of the papers in the offices generally could authorize such an affirmation. About a twelvemonth after I came to the administration of the Government Mr. Clark gave some verbal information to myself, as well as to the Secretary of State, relating to the same combinations for the dismemberment of the Union. He was listened to freely, and he then delivered the letter of Governor Gayoso, addressed to himself, of which a copy is now communicated. After his return to New Orleans he forwarded to the Secretary of State other papers, with a request that after perusal they should be burnt. This, however, was not done, and he was so informed by the Secretary of State, and that they would be held subject to his orders. These papers have not yet been found in the office. A letter, therefore, has been addressed to the former chief clerk, who may perhaps give information respecting them. As far as our memories enable us to say, they related only to the combinations before spoken of, and not at all to the corrupt receipt of money by any officer of the United States; consequently they respected what was considered as a dead matter, known to the preceding Administrations, and offering nothing new to call for investigations, which those nearest the dates of the transactions had not thought proper to institute. In the course of the communications made to me on the subject of the conspiracy of Aaron Burr I sometimes received letters, some of them anonymous, some under names true or false, expressing suspicions and insinuations against General Wilkinson; but one only of them, and that anonymous, specified any particular fact, and that fact was one of those which had been already communicated to a former Administration.