Notice is hereby given to all dealers in brandy, rum, malt, ... that the hydrometer, or brandy-prover, being the production of many years study ... is now brought to its utmost perfection.
Clarke, Richard,manufacturer.
London : printed and published according to Act of Parliament, and entered in the Hall-Book of the Company of Stationers,
[1746]
Directions for the use of the instrument.
MS. note on the B.L. copy reads: "Richd Clarke son of ye late inventor Mr John Clarke.
ESTC
Also reproduced on microfilm. Woodbridge, CT: Research Publications, Inc., 1983. The Eighteenth Century ; reel 381, no. 18.