rare c. 1905 american antique industrial commercial building basement power plant switchboard analog voltmeter designed and fabricated by the weston electric instrument company, newark, nj. the antique electrical measuring instrument is comprised of cast iron with original copper-plated finish largely intact. the ornamented faceplate contains an analog display with pointer that moves along a scale in proportion to the voltage of the circuit. a diminutive riveted joint yellow brass plaque contains a multitude of instrument patent dates. the manufacturer markings and foliated scrollwork are lightly embossed around the detachable circular-shaped face plate. standard voltmeters are used for measuring electrical potential difference between two points in a given electric circuit. the analog type contains a pointer that moves along a scale in proportion to the voltage of the circuit. the weston electrical instrument corporation was founded in new jersey by edward weston in 1888, the company's innovations included the weston standard cell, the first accurate portable voltmeters and ammeters, the first portable lightmeter, and many other electrical developments.