File:Bausch & Lomb Duboscq Type Colorimeter - DPLA - f519b463bb81f79786995cc9618140ad (page 2).jpg

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Bausch & Lomb Duboscq Type Colorimeter   (Wikidata search (Cirrus search) Wikidata query (SPARQL)  Create new Wikidata item based on this file)
Creator
InfoField
Bausch & Lomb Optical Company
Title
Bausch & Lomb Duboscq Type Colorimeter
Description
Cast iron base attached to a sloping cast iron upright supporting the reader, prisms, sample cups, and a mechanism for raising and lowering the sample cups on a focusing rail; metal knobs on each side control the height of the sample cups; two scales on the back indicate the height of the sample cups; a metal tag on the front of the upright identifies the manufacturer; a swiveling mirrored plate is mounted on the base; cast iron cover protects the sample cups and prisms. The Duboscq type colorimeter was invented by Jules Duboscq in 1870. It was a popular and enduring design, manufactured by several companies well into the 20th century, including this later model made by Bausch & Lomb. A Duboscq colorimeter determines the concentration of a substance through a visual comparison of the substance's color intensity against that of a standard solution--hence the two adjacent sample cups. This method of identification was revolutionary when first introduced, but the colorimeter was superceded by the development of the more precise spectrophotometer in the early 1940s.
Date Undated
institution QS:P195,Q5090408
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Public domain
Public domain
This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
United States
United States
This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.

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current00:53, 5 October 2022Thumbnail for version as of 00:53, 5 October 20223,287 × 4,883 (1,018 KB)DPLA bot (talk | contribs)Uploading DPLA ID f519b463bb81f79786995cc9618140ad

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