¹* * * If the said Association shall be desirous to dispose of any premises purchased by the said Association from the East India Company, the said East India Company shall the right of pre-emption, and the price shall be fixed by two appraisers, the one named on the part of the said East India Company, and the other by the Directors of the said Association; and if the said appraisers shall not agree on a price, the price shall be fixed by an umpire named by the said appraisers.