Wellcome, Wounded Man.

Depending on if you prefer sacred or secular coffee either the Quaker headquarters or the Wellcome museum 100 yards further down the road  from Euston Station provides excellently and  always includes food for thought whilst waiting for connections.
Today, one of the side exhibitions at the Wellcome was the ‘ Pharmacy of Colour’, a huge pharmacological cupboard holding a variety of exotic crushed, dried and powdered plant and other things in old fashioned jars and flasks. They had been chosen because each was used medicinally in the Middle Ages and at the same time would produce a pigment that could be used for art work.
Intriguingly, there are some art works showing the illness and cure painted with the appropriate pigment. The Wounded Man is one such. The picture is really a Physicians manual,  graphically showing every place that a body could be stabbed. The realistic blood is painted with Lac, a sticky pigment, that was also used (in the mediaeval way of thought that what resembles, must cure) to spread on wounds – probably holding the edges together quite well.
Lac's origins are in the Indian tropical forest where the bright red lac beetles pupate in their millions on the branches of trees, smothering  themselves for safety with a thick layer of hard lac. But of course, this avails them not and they are crushed to a powder and processed into pigment, medicine or varnish before they hatch.
Thus, Shellac for us, hard lac for them.