The treaty with Spain required that the commissioners for running the boundary line between the territory of the United States and His Catholic Majesty's provinces of East and West Florida should meet at the Natchez before the expiration of 6 months after the exchange of the ratifications, which was effected at Aranjuez on the 25th day of April; and the troops of His Catholic Majesty occupying any posts within the limits of the United States were within the same time period to be withdrawn. The commissioner of the United States therefore commenced his journey for the Natchez in September, and troops were ordered to occupy the posts from which the Spanish garrisons should be withdrawn. Information has been recently received of the appointment of a commissioner on the part of His Catholic Majesty for running the boundary line, but none of any appointment for the adjustment of the claims of our citizens whose vessels were captured by the armed vessels of Spain. In pursuance of the act of Congress passed in the last session for the protection and relief of American sea-men, agents were appointed, one to reside in Great Britain and the other in the West Indies. The effects of the agency in the West Indies are not yet fully ascertained, but those which have been communicated afford grounds to believe the measure will be beneficial. The agent destined to reside in Great Britain declining to accept the appointment, the business has consequently devolved on the minister of the United States in London, and will command his attention until a new agent shall be appointed. After many delays and disappointments arising out of the European war, the final arrangements for fulfilling the engagements made to the Dey and Regency of Algiers will in all present appearance be crowned with success, but under great, though inevitable, disadvantages in the pecuniary transactions occasioned by that war, which will render further provision necessary. The actual liberation of all our citizens who were prisoners in Algiers, while it gratifies every feeling of heart, is itself an earnest of a satisfactory termination of the whole negotiation. Measures are in operation for effecting treaties with the Regencies of Tunis and Tripoli.