Only a handful of theater enthusiasts would know the name Joseph Kesselring. However, many would recognize one of his most famous plays, “Arsenic and Old Lace.” His original title was “Bodies in the Cellar.” and perhaps that is the theme of this Syntax of Color.
So many colors and names of pigments have disappeared. A few names are barely recognizable. In this case, the pigment Scheeles Green, is one of those. However, its chemical relative, Emerald Green, is still used as a pigment name today. In fact, a few manufacturers still make a color that closely resembles the original Emerald Green, but contains very different materials.
Scheeles Green is a copper arsenite compound. It was discovered by the Swedish chemist, Carl Wilhelm Scheele in 1778. Scheele was a scientist of extraordinary talent. Unfortunately, his was a victim of bad luck and timing. Eight years earlier in 1770, Scheele had discovered “fire-air,” the gas we know as oxygen. Unfortunate for Scheele, Joseph Priestley made the same discovery two years later in 1774, but managed to publish his findings in 1776 and beat Scheele to claim the accolades. Scheele’s book on oxygen was distributed in 1777.
Several decades later, in an attempt to improve on Scheeles green, a copper acetoarcenite green was developed between 1800 and 1814 and was called Emerald Green as well as a host of other names. Wilhelm Sattler began manufacturing the pigment in large quantities in his German colorworks. The pigment had a hard time maintaining a solid identity. Scheeles Green had been known as Paris Green, Veronese Green, Mineral Green and Swedish Green. Emerald Green was called Mitis, as well as Paris and Veronese Green. Both their chemistry and name became intertwined and confused. Sattler’s mass production of aceto-arsenite of copper, was bestowed the name Schweinfurth Green, after the location of his color production plant. Sattler was not the only master of tortuous materials naming. During his life, Scheele had a penchant for long, convoluted names. Besides oxygen, Scheele also discovered chlorine. However, he referred to it as “dephlogisticated marine acid.” It is speculated that the complicated and ever changing name of Emerald Green was a marketing ploy to hide the fact that it contained highly toxic materials.
Emerald green can best be described as akin to permanent green light, with a higher chroma. It is a bright intense green that was not accustomed to friendly behavior and co-habitation with other pigments. It was reported to react with cadmium colors and rendered them black by a sulfur-related chemical reaction between the two pigments. A majority of lake pigments fared poorly with Emerald Green as well. On top of that, the copper arsenic compound is highly poisonous to humans and animals alike.
A modified version of the color was a popular insecticide for fruits. While one sees no indication of its use today in farming, we are reminded of copper-based preservatives in the distinct color of treated lumber used in decks and other outdoor wood construction. The biological barrier of aceto-arsenite of copper was well known in the nineteenth century as well as today.
Emerald Green took the color and designer’s world by storm. Wallpaper and paints contained Emerald Green as a colorant. It was noted that wallpaper, susceptible to insect infestation because both the paper and the paste are desired by insects, remained untouched in cases where Emerald Green was employed.
Returning now to Carl Scheele; he must have been a dare-devil, a mother’s nightmare-child who had to be watched so that he would not have the opportunity to blow up the family home. His experiments with dangerous substances continued throughout his life. Scheele worked with arsenic, cyanide and hydrogen cyanide in many experiments. With safety issues somewhat unknown or unheeded, Scheele’s health deteriorated and he died in 1786 at 43 years old. Sadly, only two days before his death he married the widow of his previous scientific collaborator so that she would inherit his business.
So the next time you come across Emerald Green, recall the “Bodies in the Cellar.” It is the complex, hidden story of people, stories behind stories, the commercial manufacturing industry and a quest for scientific discovery. Lots of stories, so little time to tell them.
Now back to reading “Arsenic and Old Lace.” Thank you, Miss Brewster, I do think I will pass on your lovely offer of a glass of homemade elderberry wine.
The Syntax of Color
Original Grammar of Color Essay
Vol: 1 No. 3 (Published: 03-09-05
(Edited 2016)