It appears copper is still used on horses, but I won’t be telling my pony-mad nieces about that.For humans the references I found for these copper pencils are mostly medical journals from the late 1800’s and usually in relation to treating conjunctivitis and other eye-infections. Apply the pencil to the eyelids to burn off the infected and granulated flesh. They ain’t kiddin’. Here’s an extract from the memoirs of a British doctor in the Near East in the late 1930’s. It seems eye infections were extremely common amongst desert peoples.
“In the long summers most out-patients had conjunctivitis and they came by the hundred for 'drops'. The more threatening condition was trachoma which affected the upper lid and could deform the thin 'plate' that kept it in shape. This led to the eyelashes wiping the cornea and, when someone cut them short they scratched it. To prevent the cornea becoming opaque, the patient came as an out-patient to hospital for an operation. The common treatment for trachoma was to pencil the inside of the lid with the 'hajar gehennam', the 'stone of hell', a copper sulphate pencil.”
Here’s another bit of a shocker from the same doctor, “The thin strip of mucous membrane was cut from the patients lower lip. It was anaesthetised with a solution of cocaine. Cocaine has such a bad reputation these days that I must digress and mention how else it was so marvellous for us. A shepherd boy had been drinking water from a jar with a thin spout, pouring it straight down his throat. It contained a leech and when I saw him, it was hanging down from one of his vocal cords. It was with a solution of cocaine that I sprayed his throat so that he would not feel my instruments trying to grab the thing. We were both very patient and won in the end.”
Never let the facts get in the way of a good story. Well, I don't really know what it feels like to have a copper pencil used on you, maybe it's not all that bad, but the whole concept just seems painful and wrong. Copper sulphate isn't generally in the same nasty league as things like sulphuric acid, but I just don't see having a piece of 'the stone of hell' stuck in my eye as being an enjoyable experience.