Sec.[Section] 1. Be it enacted by the people of the State of Illinois Represented in the General Assembly. That hereafter in all actions of Trespass quare clausum fregit, Trespass[,] and Ejectment and Forcible Entry and Detainer, as well as Forcible Detainer only, where any person or persons may be settled on any of the public lands in this State, When the same have not been offered at sale by the General Government, his, her or their possession, shall in the absence of paper title be considered on the trial as extending to the number of acres embraced by the claim of such person or persons, according to the custom of the neighborhood in which such lands may be situate; provided that such claim shall not exceed in the whole three hundred and Twenty acres, and be ascertained by land marks so plainly made, that the same may be designated from the other lands contiguous thereto, in the same neighborhood of Country And provided further that such claims shall not be plead or set up in bar of any action at any time commenced or to be commenced by a bona fide purchaser or purchasers of such lands from the United States,1 ^or person^