William Ernest Dalby, Edward Bayzard Ellington,Arthur De Wint Foote, and Louis Bell

“ In many cases the prime mover is combined with the machine in such a way that the transmitting mechanism is not distinctly differentiated from either the prime mover or the machine, as in the case of the locomotive engine. ”

“ Machinery of any kind which is driven by energy made available by the prime mover. To this group belong all machine tools, textile machinery, pumping machinery, cranes-in fact every kind of machine which requires any considerable quantity of energy to drive it. ”

“ Prime movers, by means of which the natural form of energy is transformed into mechanical energy. To this group belong all such appliances as water turbines, steam turbines, steam engines and boilers, gas producers, gas engines, oil engines, &c. ”