711.12155/1073

The Secretary of State to the Mexican Ambassador (González Roa)

Excellency: I refer to Your Excellency’s note No. 2063 of May 22, 1934, advising me of the desire of the Mexican Government that the American Commissioner be instructed to take the necessary steps to the end that the International Boundary Commission, United States and Mexico, may proceed definitely to determine the sovereignty in certain lands on the left bank of the Rio Grande opposite the town of Presidio, Texas, which your Government avers were involved in avulsive changes of that river and are consequently under the dominion and jurisdiction of Mexico, in accordance with the applicable provisions of the treaties in force between Mexico and the United States, pending a decision of the Commission.

As Your Excellency was informed in my note of acknowledgment dated May 31, 1934,14 this matter was duly referred for an expression [Page 482] of his opinion and recommendations to the American Commissioner. A reply has now been received from Mr. Lawson in which he advises that the question of these areas is greatly complicated by the obscurity and uncertainty of the existing evidence and data concerning the manner in which they were formed. This opinion is corroborated by the information in the files of the Department.

It occurs to me that it would be most helpful in the consideration of this matter if, prior to the issuance of definitive instructions of the two Governments to their respective Boundary Commissioners, an examination and careful study of the existing data respecting the areas might be undertaken to provide a basis for determining whether such data may be sufficiently reliable and accurate to enable the Commissioners to render an authoritative decision with regard to the status of the areas, or whether, on the other hand, the character of the evidence disclosed may be such as to render such a decision extremely difficult to reach, thus pointing to the desirability of further discussion of the matter by the two Governments.

In the event that this suggested procedure commends itself to Your Excellency’s Government, I shall be pleased to request the American Commissioner to direct one of the engineers of the American Section to cooperate with an engineer of the Mexican Section in carrying out such a preliminary examination and study.

Accept [etc.]

For the Secretary of State:
Sumner Welles
  1. Not printed.