William R. Day,
United States v. Biwabik Mining Company…
“ The contract was a 'lease,' the receipts were 'royalties,' and royalties, being rentals, are inherently income and have been commonly so considered. All these things seem to have affected the conclusion of the court, but, after all the dominating thought appears to be that, when land is devoted to mining it is put to only one of those productive uses of which it is capable, and that the product of the use should be called income. The land itself is the chief thing. After the mining is finished the land remains suitable for other uses ”
