Dippel's Oil (sometimes known as Bone Oil) is a nitrogenous by-product of the destructive distillation manufacture of bone char [1]. This liquid is dark colored and highly viscous with an unpleasant smell. The oil contains the organic base pyrrole. It is named after its inventor, Johann Conrad Dippel, who lived in the Castle Frankenstein and is said to be the influence for Mary Shelly's "Frankenstein."
Dippel's oil had a number of uses which are now mostly obsolete. These included medicinal uses,[2] use as an alcohol denaturant, as an ingredient in sheep dips, as an animal repellent (tradenamed as "Renardine"), as an insecticide, and as a chemical warfare harassing agent. By not being lethal, the oil was claimed to not be in breach of the Geneva Protocol. During the desert campaign of World War II, the oil was used to render wells undrinkable and thus deny their use to the enemy.[3][4]