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tory. The United States filed a replication, and proofs having been taken, the case is now before the court upon its merits.

Both parties assert title under certain articles of the treaty between the United States and Spain, made February 22, 1819, and ratified February 19, 1821. 8 Stat. 252, 254, 256.

Before examining those articles, it will be useful to refer to the diplomatic correspondence that preceded the making of the treaty. That correspondence commenced during the administration of President Madison, and was concluded under that of President Monroe. It appears that the negotiations upon the subject of the boundaries between the respective possessions of the two countries was more than once suspended because certain demands on the part of Spain were regarded by the United States as wholly inadmissible. 4 American State Papers, Foreign Relations, pp. 425, 430, 438, 439, 452, 464, 465, 466, 478. Finally, on the 24th day of October, 1818, the Spanish minister, "to avoid all cause of dispute in future," proposed to Mr. Adams, Secretary of State, that the limits of the possessions of the two governments west of the Mississippi should be designated by a line beginning "on the Gulf of Mexico, between the rivers Mermento and Calcasia, following the Arroyo Hondo, between the Adaes and Natchitoches, crossing the Rio or Red River at the thirtysecond degree of latitude, and ninety-third of longitude from London, according to Melish's map, and thence running directly north, crossing the Arkansas, the White and the Osage Rivers, till it strikes the Missouri, and then following the middle of that river to its source, so that the territory on the right bank of the said river will belong to Spain, and that on the left bank to the United States. The navigation, as well of the Missouri as of the Mississippi and Mermento, shall remain free to the subjects of both parties." He also proposed that, in order "to fix this line with more precision, and to place the landmarks which shall designate exactly the limits of both nations," each of the contracting parties should appoint a commissioner and surveyor, who should run and mark the line, and make out plans and keep journals of

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their proceedings, the result agreed upon by them to be considered part of the treaty, and have the same effect as if inserted in it. Annals of Congress, 15th Cong. 2d Sess. 1819, 1890, 1900.

To this proposition Mr. Adams, under date of October 31, 1818, replied: "Instead of it, I am authorized to propose to you the following, and to assure you that it is to be considered as the final offer on the part of the United States: Beginning at the mouth of the river Sabine, on the Gulf of Mexico, following the course of said river to the thirty-second degree of latitude; the eastern bank and all the islands in the said river to belong to the United States, and the western bank to Spain; thence, due north, to the northernmost part of the thirty-third degree of north latitude, and until it strikes the Rio Roxo, or Red River; thence, following the course of the said river, to its source, touching the chain of the Snow Mountains in latitude 37° 25' north, longitude 106° 15' west, or thereabouts, as marked on Melish's map; thence to the summit of the said mountains, and following the chain of the same to the forty-first parallel of latitude; thence, following the said parallel of latitude, 41°, to the South Sea. The northern bank of the said Red River, and all the islands therein, to belong to the United States, and the southern bank of the same to Spain." "It is believed," Mr. Adams said, "that this line will render the appointment of commissioners for fixing it more precisely unnecessary, unless it be for the purpose of ascertaining the spot where the river Sabine falls upon latitude 32° north, and the line thence due north to the Red River, and the point of latitude 41° north on the ridge of the Snow Mountains." Annals of Congress, 15th Cong. 2d Sess. 1903, 1904.

This proposition was rejected by the Spanish minister, and in his letter of November 16, 1818, he said: "I will undertake to admit the river Sabine instead of the Mermento as the boundary between the two powers, from the Gulf of Mexico, on condition that the same line proposed by you shall run due north from the point where it crosses the river Roxo (Red River) until it strikes the Mississippi, and extend thence along

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the middle of the latter to its source, leaving to Spain the territory lying to the right, and to the United States the territory lying to the left of the same." To this Mr. Adams replied under date of November 30, 1818: "As you have now declared that you are not authorized to agree, either to the course of the Red River (Rio Roxo) for the boundary, or to the fortyfirst parallel of latitude, from the Snow Mountains to the Pacific Ocean, the President deems it useless to pursue any further the attempt at an adjustment of this object by the present negotiation. I am therefore directed to state to you that the offer of a line for the western boundary, made to you in my last letter, is no longer obligatory upon this government. Reserving, then, all the rights of the United States to the ancient western boundary of the colony of Louisiana by the course of the Rio Bravo del Norte, I am," etc. Annals of Congress, 15th Cong. 2d Sess. 1908, 1942.

The negotiations were resumed in the succeeding year and the Spanish minister wrote to Mr. Adams, under date of February 1, 1819: "Having thus declared to you my readiness to meet the views of the United States in the essential point of their demand, I have to state to you that His Majesty is unable to agree to the admission of the Red River to its source, as proposed by you. This river rises within a few leagues of Sante Fé, the capital of New Mexico, and as I flatter myself the United States have no hostile intentions towards Spain, at the moment we are using all our efforts to strengthen the existing friendship between the two nations, it must be indifferent to them to accept the Arkansas instead of the Red River as the boundary. This opinion is strengthened by the well known fact, that the intermediate space between these two rivers is so much impregnated with nitre as scarcely to be susceptible of improvement. In consideration of these obvious reasons, I propose to you, that, drawing the boundary line from the Gulf of Mexico, by the river Sabine, as laid down by you, it shall follow the course of that river to its source; thence, by the ninety-fourth degree of longitude, to the Red River of Natchitoches, and along the same to the ninety-fifth degree, and crossing it at that point, to run by a line due north to the Ar

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kansas, and along it to its source; thence, by a line due west till it strikes the source of the river San Clemente, or Multnomah, in latitude 41°, and along that river to the Pacific Ocean; the whole agreeably to Melish's map." Annals of Congress, 15th Cong. 2d Sess. 2111, 2112.

The last proposition made by Mr. Adams to the Spanish minister contained the following: "Art. 3. The boundary line between the two countries, west of the Mississippi, shall begin on the Gulf of Mexico, at the mouth of the river Sabine in the sea; continuing north, along the western bank of that river, to the thirty-second degree of latitude; thence by a line due north to the degree of latitude where it strikes the Rio Roxo of Natchitoches, or Red River; thence following the course of the Rio Roxo westward, to the degree of longitude one hundred and two degrees west from London and twenty-five degrees from Washington; then, crossing the said Red River, and running thence, by a line due north, to the river Arkansas; thence following the course of the southern bank of the Arkansas, to its source in latitude forty-one degrees north; and thence, by the parallel of latitude, to the South Sea; the whole being as laid down in Melish's map of the United States, published in Philadelphia, improved to the 1st of January, 1818. But, if the source of the Arkansas River should be found to fall north or south of latitude forty-one degrees, then the line shall run from the said source due south or north, as the case may be, till it meets the said parallel of latitude fortyone degrees, and thence along the said parallel to the South Sea; the Sabine and the said Red and Arkansas Rivers, and all the islands in the same, throughout the course thus described, to belong to the United States, and the western bank of the Sabine, and the southern banks of the said Red and Arkansas Rivers throughout the line thus described to belong to Spain. And the United States hereby cede to His Catholic Majesty all their rights, claims and pretensions to the territories lying west and south of the above described line; and His Catholic Majesty cedes to the said United States all his rights, claims and pretensions to any territories east and north of said line, and, for himself, his heirs and successors, renounces

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all claims to said territories forever." The Spanish minister required that "the boundary between the two countries shall be the middle of the rivers, and that the navigation of the said rivers shall be common to both countries." Mr. Adams replied that the United States had always intended that "the property of the river should belong to them," and he insisted on that point" as an essential condition, as the means of avoiding all collision, and as a principle adopted henceforth by the United States in its treaties with its neighbors." He agreed, however, "that the navigation of the said rivers to the sea shall be common to both people." The Spanish minister assented "to the 100th degree of longitude and to remove all difficulties, to admit the 42d instead of the 43d degree of latitude from the Arkansas to the Pacific Ocean." Annals of Congress, Appendix, 15th Cong. 2d Sess. 2120, 2121, 2123.

We have alluded to this diplomatic correspondence to show the circumstances under which the treaty of 1819 was made, and to bring out distinctly two facts that are of some importance in the present discussion: 1. That the negotiators had access to the map of Melish, improved to 1818 and published at Philadelphia. 2. That the river referred to in the corre spondence as Red River was believed by the negotiators to have its source near Santa Fé and the Snow Mountains.

This brings us to the treaty itself. Its third and fourth articles are in these words:

"ART. 3. The boundary line between the two countries, west of the Mississippi, shall begin on the Gulf of Mexico, at the mouth of the river Sabine, in the sea, continuing north, along the western bank of that river to the 32d degree of latitude; thence, by a line due north, to the degree of latitude where it strikes the Rio Roxo of Natchitoches, or Red River; then following the course of the Rio Roxo, westward, to the degree of longitude 100 west from London and 23 from Washington; then, crossing the said Red River, and running thence, by a line due north, to the river Arkansas; thence, following the course of the southern bank of the Arkansas, to its source, in latitude 42 north; and thence by that parallel of latitude, to the South Sea. The whole being as laid down in Melish's