The Wealth of Nations by Part 2 Chapter 3 Page 7

other pays his profit and the rent of the landlord; and thus constitutes a revenue both to the owner of this capital, as the profits of his stock; and to some other person, as the rent of his land.

Of the produce of a great manufactory, in the same manner, one part, and that always the largest, replaces the capital of the undertaker of the work; the other pays his profit, and thus constitutes a revenue to the owner of this capital.

That part of the annual produce of the land and labour of any country which replaces a capital never is immediately employed to maintain any but productive hands. It pays the wages of productive labour only. That which is immediately destined for constituting a revenue, either as profit or as rent, may maintain indifferently either productive or unproductive hands.