All these lands thus proclaimed have been exempt from taxation. But since they were proclaimed at different periods, and also sold at different periods, so far as they are sold, it is necessary, in arriving at the value of this immunity, to ascertain what is the average period during which the lands, after being put into the market, are in the possession of the United States. This we are able to do from official returns of the Land Office. Here is a table now before me, from which it appears, that, of the lands offered for sale during a period of thirty years, large quantities were, at the expiration of the period, still on hand. Of the fourteen millions offered in Ohio during this period, more than two millions remained, while, of the nineteen millions offered in Missouri, more than twelve millions remained. Of all the lands offered during this period of _thirty_ years, more than half were still unsold.[83] And out of the aggregate of 289,961,954 acres proclaimed from the beginning down to January, 1849, notwithstanding the advancing tread of our thick-coming population, only 100,209,656 acres had been sold.[84] Now, without further pursuing these details, I assume, what cannot be questioned, as it is most clearly within the truth, that lands proclaimed are not all sold till after a period of fifty years. This estimate makes the average period during which the lands, after being surveyed and proclaimed, are actually in the possession of the United States, and free from taxation, twenty-five years. [83] Exec. Doc., 30th Cong. 2d Sess., H.R. No. 12, Table 2, p. 210. [84] Ibid., Table 6, p. 255. According to this estimate, 289,961,954 acres, proclaimed for sale, have been absolutely free from taxation during the space of twenty-five years; and yet, during this whole period, they have, without the ordinary consideration, enjoyed the protection of the State, with advantages and increased value from highways, bridges, and school-houses, all of which are supported by the adjoining proprietors, under the laws of the State, without assistance of any kind from the United States.