The Mallet brothers, Pierre and Paul, eighteenth-century French voyageurs from the "Mizuri" country, explored a vast part of what became the Louisiana Purchase. In 1739 they made a trip across the plains from the Missouri River to Santa Fe. In 1740 they encountered and descended the Canadian River, crossing the Panhandle of Texas. They continued down the Arkansas and Mississippi rivers to New Orleans. The Sieur de Bienville, governor of Louisiana, commissioned André Fabry de la Bruyère to accompany the Mallets on a return trip and map the route. The party ascended the Arkansas and entered the Canadian in 1741. Because of the river's dry bed, little progress could be made. Fabry returned to Arkansas Post and to Le Poste des Cadodaquious for horses. By the time he returned to the Canadian, the Mallets had pushed on.
Fabry returned to New Orleans via Le Poste des Cadodaquious in 1742. The Mallets made little progress and were forced to return down the Canadian and Arkansas rivers. They continued exploring out of Arkansas Post. In 1750 Pierre and three hired companions ascended the Red River, obtained horses and supplies at Le Poste des Cadodaquious, then traveled overland to the Canadian River and proceeded to Santa Fe, again across the Texas Panhandle. Pierre was arrested and sent to Mexico City and eventually to Havana. Except for Fabry's assignment, the French paid little attention to the Mallets' geographical discoveries. From them the Spanish, through depositions, gained accurate descriptions of the Arkansas River and its tributaries, but the knowledge was protected and forgotten. Fabry apparently failed to leave any evidence of what the Mallets had reported. Zebulon M. Pike, who consulted with the French, shows the course of the Canadian River as too short and southerly. Because neither French nor Spanish cartographers benefited from the Mallets' discoveries the Río Colorado of New Mexico (the Canadian River) was considered the source of the Red River until around 1820.