10 candle power, pentane burner; calibrated control tap; rotating burner head with two blueglass filters. Used for sensitometry as standard light source. No 241. With certificate of measurement of accuracy. Dibdin Argand standard lamp 1898
1 candle power; pentane burner. Used as standard light source for sensitometer. Simmance standard lamp
Ceramic acetyline burner giving a cyclindrical flame, protected from draughts by cylindrical shield. In cylindrical lamphouse, on stand. Design proposed by Sheppard and Mees, as sub-standard light source, 1910. Acetylene standard lamp 1910-1920
Standard lamp with paper shade, unsigned, United Kingdom, 1941-1975. Used in lounge of volunteers' flat at the Common Cold Research Unit, Harvard Hospital, Harnham Down, Wiltshire, England. Standard lamp from Common Cold Research Unit volunteers' flat 1941-1975