The gentleman's and trader's guide containing, the description and use of a new-invented instrument, for preventing frauds by counterfeit gold - Bradford, William ([s.n.], 1754)
"The instrument is neatly made in brass, and very easily portable in the pocket ... Any person, by sending to the authors, may have an instrument made to weigh and prove any larger coin or utensils of gold or silver, than this instrument is design'd for.". - Abstract of His Majesty's royal letters patent: p. [1]-[4]. - Advertisements (5 p.) at end. - Goldsmiths'-Kress no. 08933. - OCLC, 23864353. - Reproduction of original from Goldsmiths' Library, University of London
Keywords: aAssaying apparatus; aCounterfeits and counterfeiting; aGold xAssaying; Assaying apparatus; Counterfeits and counterfeiting; Gold -- Assaying