221 THE INDUSTRIAL REVOLUTION OF 1946 — No. 10 The folly of 'fudging a reckoning' The greatest enemy of fuel efficiency, for which the call is so insistent still, is lack of precision. Without full records of fuel consumption in relation to output, no management can know how well—or ill—the drive for more work from less fuel is going. Without proper instruments no boiler- house or process staff can check the thermal efficiency of their plant and practice. The job that must be done now can't be done by guess-work.