An authentic narrative of the loss of the American brig Commerce : wrecked on the western coast of Africa, in the month of August, 1815 : with an account of the sufferings of the surviving officers and crew, who were enslaved by the wandering Arabs, on the Africa desart, or Zahahrah : and observations historical, geographical, &c. ... / by James Riley ... ; preceded by a brief sketch of the author's life ... ; illustrated and embellished with ten copperplate engravings ; revised, and his life continued, by the author, in January, 1828 (1851)