Forman in 1789-1790, made a journey down the Ohio, and mentions the arrival, at Louisville, of four tobacco boats, on their way to New Orleans.[52] Furs were sent up the Ohio from Illinois to Pittsburg, as early as 1790, as is shown by the following from a letter written by St. Clair, "There is no doubt that the furs of that country might be brought up the Ohio River at as little or even less expense than attends the carriage of them to Canada. It has been tried by one person, a Mr. Vigo, and found to answer; although the goods he carried out were transported by land from Philadelphia to Pittsburg, and loaded with an impost the competitors were free from, they came to market on better terms than those from Canada. Could these also be subjected to it, a decided advantage would be given to the American trader."[53] Pope who journeyed down the Mississippi in 1791, speaks of meeting several boats bound down the river, loaded with bacon, butter, flour, tobacco, and plank, and also two large Pittsburg boats loaded with flour.[54] "The Walnut Hills about ten miles below the Yasous River" were fixed as the boundary line by the King of Spain, and United States citizens were not allowed to live in Spanish territory unless they put themselves under the laws, banners, and protection of Spain. Private adventurers from New York, Philadelphia, and Baltimore, carried on a tolerable trade at New Orleans, and had an advance of cent per cent on their goods, which were nevertheless cheaper than Spanish importations.[55] October 27, 1795 a treaty was made with Spain containing the following provisions: "It is likewise agreed that the western boundary of the United States which separates them from the Spanish Colony of Louisiana, is in the middle of the channel or bed of the River Mississippi, from the northern boundary of the said States to the completion of the 31st degree of latitude north of the Equator. And his Catholic Majesty has likewise agreed that the navigation of the said river in its whole breadth, from its source to the ocean, shall be free only to his subjects, and the citizens of the United States, unless he should extend this privilege to the subjects of other powers by special convention."[56] "And in consequence of the stipulation contained in the fourth article, His Catholic Majesty will permit the citizens of the United States, for the space of three years from this time, to deposit their merchandise and effects in the port of New Orleans, and to export them from thence, without paying any other duty than a fair price for the hire of the Stores, and his Majesty promises either to continue this permission, if he finds, during that time that it is not prejudicial to the interests of Spain, or if he should not agree to continue it there, he will assign to them, on another part of the banks of the Mississippi, an equivalent establishment."[57]