calorimetric measurements have shown that the efficiency of the human machine is about one-fifth, i.
"The Mechanism of Life"
Stéphane Leduc
The investigation of Lord and Haas in this country, Mabler in France, and Bunte in Germany, all show that Dulong's formula gives results nearly identical with those obtained from calorimetric tests and may be safely applied to all solid fuels except cannel coal, lignite, turf and wood, provided the ultimate analysis is correct.
"Steam, Its Generation and Use"
Babcock & Wilcox Co.