
    O’Neal vs. Duncan.
   Where a tract of land was sold by the sheriff under au execution against the defendant, in an action of trespass to try titles, by the purchaser against the defendant, the defendant will not be permitted to give evidence that the title of the land was not in himself, but in another whose tenant he was.

The Sheriff’s title, (being the organ of the law to convey the defendant’s right,) is considered as the deed of the defendant, and operates as an estoppel.  