Magnesia was originally a strip of land along the coast of Thessaly in eastern Greece. It was named for the Magnetes tribe who settled it. The origin of the Magnetes shades back into myth: Magnes and his brother Macedon were among the sons of Zeus who founded the various Greek tribes. When the Magnetes colonized other regions, they are believed to have founded two cities in Asia Minor, Magnesia on the Maeander and Magnesia ad Sipylum. Today Magnesia is a regional unit in Greece.
Magnets are named for Magnesia; the word originally came from magnítis líthos or Magnesian stone, which referred to what we now call magnetite. This is an iron ore that under certain circumstances can become magnetized naturally, producing a lodestone. These natural magnets introduced humankind to magnetism. An alternate explanation, cited by Pliny the Elder, involves a shepherd called Magnes who observed the effects of magnetite when the nails in his shoes were attracted to the stone he was walking across on Mount Ida on Crete. However, I'm inclined to file this one under "legend."
Along with magnetite, certain types of magnesium ores are found in Greece. Overall, magnesium is the eighth most common element in Earth's crust by mass, and incidentally the eleventh most abundant by mass in your body. Although magnesium is so common, it's rarely found alone because it's very reactive. Magnesium also came by its name from its early association with Magnesia. (Note that magnesium itself is not magnetic.)
The element manganese traces its name back to Magnesia too. The name magnítis líthos for magnetite became magnes, and it shared this name with another black mineral identified today as manganese dioxide. The name manganese for the element eventually evolved out of magnes. Slippery thing, language.
Finally we come to milk of magnesia, a suspension of magnesium hydroxide in water that has a milky appearance. It became known as a treatment for digestive complaints in the 19th century, and in 1873, Charles Henry Phillips gave the name Phillips' Milk of Magnesia to his magnesium hydroxide suspension, which was marketed as an antacid and laxative. The US Patent Office lists Bayer as the current owner of the trademark.
So there you go: from Zeus's children to magnets to magnesium and manganese to a laxative. Think of ancient Greece the next time you see one of those blue bottles.
- Information on magnesium in the human body from the Linus Pauling Institute's Micronutrient Information Center
- Newspaper clipping from the Stamford Historical Society giving a brief history of the Charles H. Phillips Chemical Co., which grew out of the work of C. H. Phillips in his Stamford, CT laboratory