I'm not harshin' on ya, nu-be, just throwing in a few extra bits of info:

"As I remember, it's also the origin of the 'Rx' in perscriptions."

This bit is somewhat controversial, as there isn't really sufficient information to make the connection. I've seen a lot of the sites out there that say there is and few of them are academically credible.

"Ancient Egypt was known to the ancients as 'Khem', whence comes chemistry..;)"

To add to that:

alchemy - 14c., from O.Fr. alkemie, from M.L. alkimia, from Ar. al-kimiya, from Gk. khemeioa, all meaning "alchemy," perhaps from an old name for Egypt (Khemia, lit. "land of black earth," found in Plutarch), or from Gk. khumatos "that which is poured out," from khein "to pour." Possibly a confusion of the two.

Also:

E.A. Wallis Budge (THE egyptologist) notes in "Egyptian Magic" (pg.55-58) that this is the Eye of Horus. While it is sometimes seen in pairs -- one black, the other white -- as the eyes of Ra and Osiris, or the sun and moon: "... speaking generally, when the Egyptians wore the Utjat as an amulet they intended it to bring them the blessings of strength, vigor, protection, safety, good health and the like, and they had in their minds the Eye of Horus, probably the white on, or the Sun."