The great purpose of the French in the new world was trade. Their expeditions, excluding those of the missionaries, were commercial in nature. With them gold hunting was not a primary consideration, as was the case with the Spaniards, and that for the simple reason that no gold could be found. Nor were they seeking a refuge from persecution like the English. The great fur trade was being developed by them. This trade was carried on with the Indians, and in all sections where captives in war or kidnapped Indians were purchased from the natives, such purchase was usually a part of the trade in furs. The custom of purchasing Indians originated with the early explorers and discoverers. Sometimes such a purchase was made for a purely commercial reason: to obtain a slave to perform some certain labor. At other times the buyer was moved by an humanitarian motive: to save an Indian from torture or death at the hands of his captors. The purchased Indian might then be allowed to return to his own tribe and be retained as a slave at the will of his new master. In 1678, Du Lhut, when setting out from Montreal on his travels westward, bought an Indian to act as a guide.[211] Du Tisné, in 1719, similarly acquired some slaves from a chief at Natchitoches.[212] In 1724, de Bourgmont purchased a considerable number of slaves from the Kansas tribe. Mention is made of fifteen at one time, six at another.[213] For these he was forced to pay double price, as the Indians stated that the year before, a Frenchman had given such a price to a party of Illinois who were with them.[214] Sometimes the slaves obtained by these explorers and traders were used in their own expeditions. At other times, they were sent back to the settlement along with other merchandise. De Bourgmont sent some of those whom he purchased back to New Orleans. La Vérendrye, also, in 1731, sent back slaves to the French settlements, and in writing of his action implied that he thought he deserved much credit for furnishing the colonists with slaves.[215] Until well into the latter half of the eighteenth century Indian slaves were held by the settlers of Detroit, who obtained them in trade with friendly Indians who in turn took them in war with the Pawnee, Osage, Choctaw and other western tribes.[216] In 1741, the so-called “Nation of the Serpent” entirely destroyed seventeen villages, killed all the men and older women, made slaves of the young women, and traded them for horses and other merchandise.[217] A report to the home government in 1720, concerning Natchitoches, declared that the most extensive commerce which could be carried on with the Indians of that section, would be in slaves, horses, skins, etc.[218] Another report sent by La Salle told of the Alabama Indians bringing twenty-seven or twenty-eight Mobile Indian women and children into the colony, and disposing of them to the French.[219]