Such parts of the act passed March 20, 1811,¹ entitled “an act providing for the settlement of certain disputed titles to lands north and west of the rivers Ohio and Allegheny and Conewango creek,” as have expired, are hereby revived and re-enacted, and all agreements heretofore made, or which hereafter shall be made, within two years from the first day of April next, in conformity to the provisions therein contained, for any of the said lands lying north and west of the rivers Ohio and Allegheny and Conewango creek, including the unsold depreciation surveys, shall be as valid as if the same had been made within the time specified in said act.