SIR:[15] Being charged by the Constitution with the prosecution of the existing war with Mexico, I deem it proper, in the exercise of an undoubted belligerent right, to order that military contributions be levied upon the enemy in such of their ports or other places as now are or may be hereafter in the possession of our land and naval forces by conquest, and that the same be collected and applied toward defraying the expenses of the war. As one means of effecting this object, the blockade at such conquered ports will be raised, and they will be opened to our own commerce and that of all neutral nations in articles not contraband of war during our military occupation of them, and duties on tonnage and imports will be levied and collected through the agency of our military and naval officers in command at such ports, acting under orders from the War and Navy Departments. I transmit to you herewith, for your information and guidance, a copy of a communication addressed by me to the Secretary of the Treasury on the 23d instant, instructing him to examine the existing Mexican tariff and to report to me, for my consideration, a scale of duties which he would recommend to be levied on tonnage and imports in such conquered ports, together with such regulations as he would propose as necessary and proper in order to carry this policy into effect; and also a copy of the report of the Secretary of the Treasury made on the 30th instant in answer to my communication to him. The scale of duties and the regulations for their collection as military contributions exacted from the enemy, recommended by the Secretary of the Treasury in this report, have been approved by me. You will, after consulting with the Secretary of the Navy, so as to secure concert of action between the War and Navy Departments, issue the necessary orders to carry the measure proposed into immediate effect. JAMES K. POLK. [Footnote 15: Addressed to the Secretaries of War and of the Navy.] TREASURY DEPARTMENT, _June 10, 1847_. The PRESIDENT. SIR: In compliance with your directions, I have examined the questions presented by the Secretary of War in regard to the military contributions proposed to be levied in Mexico under the tariff and regulations sanctioned by you on the 31st of March last, and respectfully recommend the following modifications, namely: First. On all manufactures of cotton, or of cotton mixed with any other material except wool, worsted, and silk, in the piece or in any other form, a duty, as a military contribution, of 30 per cent _ad valorem_. Second. When goods on which the duties are levied by weight are imported into said ports in the package, the duties shall be collected on the net weight only; and in all cases an allowance shall be made for all deficiencies, leakage, breakage, or damage proved to have actually occurred during the voyage of importation, and made known before the goods are warehoused.