The proviso of the seventeenth article just mentioned required that the lands therein ceded should be surveyed, after the manner of surveying the public lands of the United States, and should be appraised by two commissioners, one of whom should be appointed by the United States and the other by the Cherokee Nation, such appraisement not to average less than $1.25 per acre. After such appraisement, the lands were to be sold under the direction of the Secretary of the Interior on sealed bids, in tracts of not exceeding 160 acres each, for cash, with the proviso that nothing should forbid the sale, if deemed for the best interests of the Indians, of the entire tract of "neutral land" (except the portion occupied by actual settlers) in one body to any responsible party for cash for a sum not less than $800,000. An exception was made as to the lands which were occupied by bona fide white settlers at the date of the signing of the treaty, who were allowed the privilege of purchasing at the appraised value, exclusive of their improvements, in quantities of not exceeding 160 acres each, to include such improvements. The language of this seventeenth article being somewhat obscure and subject to different interpretations as to the actual intent concerning the method of disposing of the "Cherokee strip," no action was taken toward its survey and sale until the year 1872, when by an act of Congress[601] provision was made for the appraisal of that portion of it lying east of Arkansas River at not less than $2 per acre, and the portion west of that river at not less than $1.50 per acre. Further provision was also made, by the same act, for its disposal on certain conditions to actual settlers, and any portion not being rendered amenable to these conditions was to be sold on sealed bids at not less than the minimum price fixed by the act. A considerable quantity of the most fertile portion of the tract was thus disposed of to actual settlers, though, as an encouragement to the sale, Congress was induced to pass an act[602] extending the limit of payment required of settlers to January 1, 1875. The price fixed by the act of 1872 being so high as to render the remainder of the land unattractive to settlers, a subsequent act of Congress[603] directed that all unsold portions of the said tract should be offered through the General Land Office to settlers at $1.25 per acre, for the period of one year, and that all land remaining unsold at the expiration of that period should be sold for cash at not less than $1 per acre. This act was conditional upon the approval of the Cherokee national council, which assent was promptly given, and the lands were disposed of under its provisions.