Upon proof by the authorized agent of the State, before the Secretary of the Interior or such officer as he may designate, that any of the lands purchased by any person from the United States, prior to March 2, 1855, were “swamp lands”, within the true intent and meaning of the Act entitled “An Act to enable the State of Arkansas and other States to reclaim the swamp lands within their limits”, approved September 28, 1850, the purchase money shall be paid over to the State wherein said land is situate; and when the lands have been located by warrant or scrip, the said State shall be authorized to locate a like quantity of any of the public lands subject to entry, at $1.25 per acre, or less, and patents shall issue therefor. The decision of the Secretary or such officer shall be first approved by the Secretary of the Interior.