Duboscq Colorimeter, Medical - Scientific Curiosity Device, Analysis J.PETER LYON This monocular device for the simultaneous observation of two colored liquids was designed in 1854 by Jules Duboscq (1817-1886), an optical engineer and son-in-law of Jean Baptiste Soleil, whose activities he took over under the name Maison Duboscq, before joining forces with François Philibert Pellin (1847-1923), with the Duboscq-Pellin company. This type of device was used until the 1950s, replaced by more precise electric photometers. Condition: Used: An item that has been used. See the seller's description for more details... Used: An item that has been used. any imperfections. Period: 1900 - 1950 Type: Medicine Subtype: Instrument Country of manufacture: France Material: Metal