This I conceive to be a theory founded upon facts, and therefore an infallible one. If the blacks were permitted to remain in their own country, they would double themselves every fifteen years. In proportion to such increase will be the demand for manufactures. Cotton and indigo grow spontaneously in most parts of Africa; a consideration this of no small consequence to the manufacturing towns of Great Britain. It opens a most immense, glorious, and happy prospect—the clothing, &c. of a continent ten thousand miles in circumference, and immensely rich in productions of every denomination in return for manufactures.