"[T]he new theory is opposed, not to the real fundamental principle of Carnot, but to the addition "no heat is lost;" for it is... possible that in the production of work... a certain portion of heat may be consumed, and a further portion transmitted from a warm body to a cold one; and both portions may stand in a certain definite relation to the quantity of work produced.<!--p. 17->"
January 1, 1970
https://en.wikiquote.org/wiki/Rudolf_Clausius