From and after the first day of September next, it shall be lawful for the secretary of the land office to issue warrants for any vacant and unappropriated lands within the limits of the purchase made of the Indians in the year 1784, and lying east of the Allegheny and Conewango creek, either improved or unimproved, at the rate of twenty-six dollars and sixty-six cents for every hundred acres.
64 P.S. § 112