Wiktionary
donkey pumps
n. (donkey pump English)
Usage examples of "donkey pumps".
A score of rocking-donkey pumps bobbed up and down in patient, unchanging motion, great metal monstrosities bringing up the thick crude and sending it into a long warehouse-like building where the actual refining and processing of the gas were accomplished.
To the north were at least a dozen rocking-donkey pumps, nodding away in the growing light.