Mummy, unicorn's horn, and bezoars appealed to the imagination because of their unusual character, but even the most commonplace substances might develop supposedly medicinal virtues if they had unusual or gruesome associations. Usnea was a substance of this nature. It was moss; not ordinary moss, but moss scraped from the skull of a criminal who had been hung in chains. Usnea was an official drug in the pharmacopeia until the nineteenth century; it was carried by all apothecary shops, and the first edition of the Encyclopedia Britannica devoted a section to its curative properties. Usnea was present in the prescriptions of the best physicians over a period extending from the Middle Ages until well after the American Revolution.
Source: Howard W. Haggard, Devils, drugs, and doctors (1929).

Paracelsus recommended the 'moss', or lichen, that grew on a dead man's skull for seizures and 'disorders of the head', and to bind wounds, on the basis that the 'vital spirit' released at death would be transferred from the skull into the lichen that started to grow on its surface. The fact that these skull-grown lichens were quite rare only increased the value of the cure. Skull moss seems to have been a particularly popular remedy in England and Ireland, perhaps because in these countries dead criminals were often left on public display until their flesh started to rot away and things began to grow on their bones. In 1694 it was reported that London druggists sold suitably mossy skulls for 8 to 11 shillings each, depending on the size and the amount of growth on them. . .

There were reports of people growing moss on stones and then spreading it onto the skulls of criminals, as a way of harvesting the tiny green plants for sale. In practice, apothecaries probably used anything that grew on skulls, and some things that did not grow on skulls, to maintain their supplies.

Suddenly, I was immersed in the brightest light I have ever seen. I moved my head from side to side and all I could see was bright white light, similar in appearance to arc welding light. This next part is strange. I distinctly remember feeling weightless, and that my feet were no longer touching the ground. For some reason, it felt like a number of seconds transpired, even though I realize that lightning strikes are instantaneous. A deafening explosion followed, and I found myself on the ground with the others. Sean was collapsed and huddled on his knees. Smoke was pouring from his back. I rushed over to him and checked his pulse and breathing. He was still alive. I put out the embers on his back and elbows and carried him down the path towards the parking lot, with the rest of the group following.

Charlotte Wolfe had three rotten teeth, so she went to Max Feldman, a dentist specializing in oral surgery, to have them pulled. When the surgery was over, however, Wolfe complained of pain in a strange place: the pinky finger of her right hand. It turned out to be a possible fracture, and she sued Feldman.

Feldman countered that it wasn't his fault, and he told the judge this story:

Wolfe was strapped to the dentist's chair (apparently a common procedure then), and was given nitrous oxide, an anesthesia better known as laughing gas. What happened next was no laughing matter.

Defendant's story is that plaintiff was strapped to the operating chair; that a short time later, after plaintiff was in the excitement stage of nitrous oxide anaesthesia and as he moved closer to the chair to adjust the suction aspirator, plaintiff, despite the limited movement of the strapped wrist, clutched his testicles with a painful grip, which required the use of great force to release.

It was incumbent on him, during the time the patient was in the so-called 'fighting stage' reached by patients undergoing anesthesia by nitrous oxide, not to place his body in such a position as to permit plaintiff's hands to interfere with him to such an extent as to require the application of force sufficiently severe to cause her physical injury.