JF Ptak Science Books Quick Post
This is a short Sherlockian episode found in the pages of the 1877 volume of Scientific American. It seems that people were becoming ill for unknown reasons (and not further specified in the short note) that soon was found to be: the color green. Green pigment. Green pigment in the fabric of the patients’ bedroom curtains.
It was found that once the curtains were removed, the patients recovered.
The green in this case was called Scheele’s Green, named for its inventor, the German/Swedish chemist Carl Wilhelm Scheele, who brought it into the world in 1775. Unfortunately it was found that this green was particularly toxic, as it employed a large quantity of arsenic, which proved to be unstable and became a noxious chemical pollutant.
It was replaced in the late 19th century by other greens (such as cobalt green), though it did have a short rebirth in the 1930’s when it was used as an insecticide. This was in marked contrast to its earlier use as a food dye for candies.