¶1It is made the duty of the Commissioner of the General Land Office, to issue patents upon such surveys only, as have been made in conformity to law. But it is proposed, by this suit, to compel the issuance of a patent upon a survey made confessedly contrary to the literal direction of a plain statute. (Laws 6th Leg. 128, ch. § 4.) There can be no better settled principle, by the oft repeated decisions of this court, than that a mandamus will not lie to compel a public officer to *564perform an act, which is not a duty clearly prescribed and enjoined by law. A mandamus will not lie to compel the performance of an act, contrary to the provision of a statute which is merely directory. (Horton v. Pace, 9 Tex. Rep. 81; Commissioner General Land Office v. Smith, 5 Id. 471; Cullem v. Latimer, 4 Id. 329; Bracken v. Wells, 3 Id. 88.)
¶2The words of the statute convey a plain meaning, which cannot be mistaken. There is no room to deduce a different meaning, by construction, from that which is plainly expressed; and we find nothing in the record to warrant the conclusion, that the legislature did not mean what they have expressed in words, if it were admissible to vary the meaning of a plain statute, by matter of fact outside of it. It is scarcely necessary to say, that a practice in disregard of a former statute, cannot have such authority as to require the court to sanction and enforce, by its direct action for that purpose, a like disregard of the present. There is no error in the judgment, and it is affirmed.
¶3Judgment affirmed.