In the laws of the republic of Texas, a certificate issued under authority of an act of 1839, which provided that every person immigrate lng to the republic between October 1, 1837, and January 1, 1840, who was the head of a family and actually resided within the government with his or her family should be entitled to a grant of 640 acres of land, to be held under such a certificate for three years, and then conveyed by absolute deed to the settler, if in the mean time he had resided permanently within the republic and performed all the duties required of citizens. Cannon v. Vaughan, 12 Tex. 401; Turner v. Hart 10 Tex. 441.