Your favor of Nov. 23. after a very long passage is recieved, and with it the Map which you have been so kind as to send me, for which I return you many thanks. it is handsomely executed and on a well chosen scale; giving a luminous view of the comparative possessions of different powers in our America. it is on account of the value I set on it that I will make some suggestions.1 by the Charter of Louis XIV. all the country comprehending the waters which flow into the Missisipi was made a part of Louisiana. consequently it’s northern boundary was the summit of the highlands in which it’s Northern waters rise. but by the Xth art. of the treaty of Utrecht, France & England agreed to appoint Commissaries to settle the boundary between their possessions in that quarter; and those Commrs settled it at the 49th degree of Lat. see Hutchinson’s topographical description of Louisiana. pa. 7. this it was which induced the British Commrs in settling the boundary with us, to follow the Northern waterline to the Lake of the woods at the latitude of 49° and then go off on that parallel. this then is the true Northern boundary of Louisiana.

The Western boundary of Louisiana is, rightfully, the Rio Bravo, (it’s main stream) from it’s mouth to it’s source, and thence along the highlands & mountains dividing the waters of the Missipi from those of the Pacific. the usurpations of Spain on the East side of that river have induced geographers to suppose the Puerco or Salado to be the boundary. the line along the highlands stands on the Charter of Louis XIV. that of the Rio Bravo, on the circumstance that when La Sale took possession of the bay of St Bernard, Panuco was the nearest possession of Spain, & the Rio Bravo the natural halfway boundary between them.

On the waters of the Pacific we can found no claim in right of Louisiana. if we claim that country at all, it must be on Astor’s settlement near the mouth of the Columbia, and the principle of the jus gentium of America that when a civilized nation takes possession of the mouth of a river in a new country, that possession is considered as including all it’s waters. the line of latitude of the Southern source of the Multnomah might be claimed as appurtenant to Astoria. for it’s Northern boundary, I believe an understanding has been come to between our government & Russia, which might be known from some of it’s members. I do not know it.

Altho the irksomeness of writing, which you may percieve from the present letter, and it’s labor, oblige me now to withdraw from letter writing yet the wish that your map should set to rights the ideas of our own countrymen as well as foreign nations as to our correct boundaries has induced me to make these suggestions that you may bestow on them whatever enquiry they may merit. I salute you with esteem & respect.