"Each of said ships to make four voyages per annum; one shall leave New Orleans every three months; one shall leave Baltimore every three months, touching at Norfolk and Charleston; and one shall leave New York every three months, touching at Savannah; all having liberty to touch at any of the West India Islands; and to proceed thence to Liberia, touching at any of the islands or ports on the coast of Africa; thence to Gibraltar, carrying the Mediterranean mails; thence to Cadiz, or some other Spanish port to be designated by the Secretary of the Navy; thence to Lisbon; thence to Brest, or some other French port to be designated as above; thence, to London, and back to the place of departure, bringing and carrying the mails to and from said ports.
"The said contractors shall further agree to carry to Liberia so many emigrants being free persons of color, and not exceeding twenty-five hundred for each voyage, as the American Colonization Society may require, upon the payment by said Society of ten dollars for each emigrant over twelve years of age, and five dollars for each one under that age, these sums, respectively, to include all charges for baggage of emigrants and the daily supply of sailors' rations. The contractors, also, to carry, bring back, and accommodate, free from charge, all necessary agents of the said Society.
"The Secretary of the Navy shall further stipulate to advance to said contractors, as the building of said ships shall progress, two thirds of the amount expended thereon; such advances to be made in the bonds of the United States, payable thirty years after date, and bearing five per cent. interest, and not to exceed six hundred thousand dollars for each ship. And the said contractors shall stipulate to repay the said advances in equal annual instalments, with interest from the date of the completion of said ships until the termination of the contract, which shall continue fifteen years from the commencement of the service. The Secretary of the Navy to require ample security for the faithful performance of the contract, and to reserve a lien upon the ships for the sum advanced. The Government to pay said contractors forty thousand dollars for each trip, or four hundred and eighty thousand dollars per annum.