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Scientific, Instrument, Physics, Electricity, Voltmeter, Antique, New Jersey, Early 20th Century, Prop Rental

Weston Electrical Instrument Co.
Portable Voltmeter and Ammeter
Newark, New Jersey: Early 20th Century
Wood, glass, metal and leather, electrical components
10 inches high, 12 inches wide, 4.5 inches deep

Antique volt and ampere testing meter in a wood box with a leather handle. There are two metal plates reading “Volts” and “Amperes” attached to the front with the patent information. The voltage patents were obtained in 1888 and 1890; the amperage plate lists five patents between 1894 and 1896, and has the serial number for this particular instrument. A paper label attached to the lower left corner of the front is stamped with a date that it was apparently calibrated, since it reads “Traceable N.B.S.” N.B.S. stands for the United States National Bureau of Standards. This helps date this instrument to after 1901, when the N.B.S. was renamed, having previously been known as the Office of Standard Weights and Measures.

Product description continues below.


The manufacturer, the Weston Electrical Instrument Corporation produced the first accurate portable voltmeters and ammeters. The company was founded in 1888 by Dr. Edward Weston (1850-1936). A prolific inventor, Weston got his start inventing and producing dynamos for the electroplating industry after he emigrated to the U.S. in 1870. He followed by inventing and manufacturing electric lighting systems and bulbs and became a leading supplier of arc lighting systems, including the lighting for the Brooklyn Bridge when it opened in 1883. By 1886 he had been granted 186 patents and shifted his focus to manufacturing measuring instruments. After some research and development, he closed his lighting company and started the Weston Electrical Instrument Company. In addition to portable voltmeters and ammeters, the company produced other innovative electrical products including the Weston standard cell and the first portable light meter. Edward Weston was an early contributor to the founding of the Newark Technical School, which eventually became New Jersey Institute of Technology. He is in the New Jersey Inventors Hall of Fame. Edward Weston was joined in business by his son Edward Faraday Weston.

Condition: Generally very good with the usual overall wear from use as expected from a utilitarian object. Leather strap replaced. Apparently in working condition though rented only as a vintage decorative artifact and curiosity, not for use with electricity or other power source.


“Weston Electrical Instrument Corporation.” FTL Design History of Technology. 28 September 2015. (20 October 2016).