X marks the spot

The R symbol is well known as the sign of a prescription, and it is often said that it is R_x, a shortened version of the Latin word recipe, take. But R is not R plus x; it is a corruption of a symbol that was once used by the ancient Egyptians to signify the utchat, the eye of Horus.

As with so many ancient gods, Horus had several manifestations, which are often confused with each other. Originally he was Horus the Elder, the falcon headed god of the sky. Other manifestations included a war god, two different forms of sun god, and various children of Isis and Osiris, also known as Harsiesis, Harpakhrad, Harpokrates, and Horus the Younger.

Horus the Elder had two eyes, the sun and the moon. Set, the god of night and darkness, evil and death, stole the sun, but Thoth made a treaty between them and allotted the day to Horus and the night to Set. Set was not content, however, and continued to make war on Horus by regularly cutting off parts of the moon, while Thoth renewed it each month. An interesting explanation of a natural phenomenon.

In Finnegans Wake James Joyce created a cod book title, “How to Pull a Good Horuscoup even when Oldsire is Dead to the World” (105.28). This alludes to another version of the story. Set killed Osiris and cut his body into pieces. Isis, the wife of Osiris, found all the pieces (except the penis, for which she fabricated a replacement), put them together, and conceived Horus the Younger. To avenge his father, Horus made war on Set, and during a battle lost an eye, which was then miraculously restored by Thoth.

Because of these restorations, the eye of Horus became a potent symbol of good fortune and healing, later adopted by the Greeks, Arabs, and others.

In the drawing on the left it is represented in a form that is recognisable as the source of the R symbol, although more often it was drawn as shown on the right—for example, on the Rosetta stone.

Horus had other medical connections. His four sons were guardians, each with one of the goddesses, of the enurned organs of the dead:

• Amset, the human headed god of the south, was guardian of the liver with Isis

• Hapi, the dog headed god of the north, was guardian of the lungs with Nephtys

• Duamutef, the jackal headed god of the east, was guardian of the stomach with Net

• Qebhsneuf, the hawk headed god of the west, was guardian of the intestines with Selqet.

Prior to embalming, these organs were removed, wrapped in linen, and placed in so called Canopic jars, the lids of which were shaped as the heads of the gods who guarded them. Examples are to be seen in the Louvre.

In recent years the belief that the sign R is formed from R (= recipe) plus x (somehow indicating an abbreviation) has led to the proliferation of numerous similar abbreviations, used as shorthand in case notes: H_x for history, S _x for symptoms, I_xfor investigations, D_x for diagnosis, M_x for management, Ab_x for antibiotics. I expect that before long we shall be seeing E_x for examination and perhaps even X_x for xray.

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