Editing Benjamin Thompson (section)

===Light and photometry===
Rumford worked in [[photometry (optics)|photometry]], the measurement of light.  He made a photometer and introduced the [[Candela#History|standard candle]], the predecessor of the [[candela]], as a unit of [[luminous intensity]].  His standard candle was made from the oil of a sperm whale, to rigid specifications.<ref>{{cite book
 | title = International Encyclopedia of Ergonomics and Human Factors
 | author = Waldemar Karwowski
 | publisher = CRC Press
 | year = 2006
 | isbn = 978-0-415-30430-6
 | page = 1478
 | url = https://books.google.com/books?id=tl5YAj10BcsC&q=benjamin-thompson++photometry+candle&pg=PA1478
 }}</ref> He also published studies of "illusory" or subjective complementary colours, induced by the shadows created by two lights, one white and one coloured; these observations were cited and generalized by [[Michel-Eugène Chevreul]] as his "law of simultaneous colour contrast" in 1839.<ref>{{cite book
 | title = The Complete Works of Count Rumford, Vol. 5
 | author = Benjamin Thompson, Count Rumford
 | publisher = American Academy of Arts and Sciences
 | year = 1876
 | url = https://books.google.com/books?id=udu4AAAAIAAJ&q=%22count+rumford%22+experiments+coloured+shadows&pg=PA51}}</ref>