Note 116 — Chapter VIII

The fact here referred to is easily seen if it is supposed that an engine is supplied with steam at a temperature of 400° above absolute zero and works it, without waste, down to a temperature of 200°. Suppose one inventor to adapt the engine to the use of steam of a range from 500° down to 200°, while another works his engine, with equally effective provision against losses, between the limits of 400° and 100°, an equal range with a lower mean. The first case gives an efficiency of one-half, the second three-fifths, and the third three-fourths, the last giving the highest effect.