This publication contains the report, dated 25 November 1825 of a diplomatic and commercial mission to Southeastern Asia by Mr. Joseph Balestier, the United States Consul at Singapore, at the request of the President of the United States. Included are his correspondences with the Secretary of State, Mr John M. Clayton and many others related to the mission. On pages 88-89 is a copy of the treaty he signed on behalf of the United States with Omar Ali, the Sultan of Borneo on 23 Jume 1950.