The Weston cell, is a wet-chemical cell that produces a highly stable voltage suitable as a laboratory standard for calibration of voltmeters. Invented by Edward Weston in 1893, it was adopted as the International Standard for EMF between 1911 and 1990.[1] This is a type of standard cell, which is a battery that produces a precisely known voltage in laboratory conditions at 20 degrees centigrade.[2]Brass cylinder with 4 connections at top. Two marked 'A' and the other two marked 'B'. Black plastic nob in the centre top. Written at top Weston Normal Cell I-0183 INT VOLTS AT 20 degrees CWeston Normal Cell H Tinsley & Co, London S E No 50498 No 8910weston cell, wet-chemical cell, stable voltage, voltmeters, edward weston, scientific instrument

The photronic cell used in electrical experiments to demonstrate control of currents and lighting.Black bakelite circular case with two socket pins. Circular open top with tiny copper pins around the edge. Box Black and whiteName of maker and item: WESTON PHOTRONIC CELL MODEL 594 PAT PEND NEWARK N J U S Aweston, photronic cell, socket pins, copper pins, bakelite, experimental, electrical currents, lighting

Two Weston Cells, H.Tinsley & Co London