Mercury
Mercury names 4 different subjects across the 6 encyclopedias on this shelf. Each is set out below.
Mercury an important metal
Aiton's Encyclopedia (1910)
an important metal. It is found in a pure state to some extent, but usually in combination with sulphur, from which it is separated by roasting. The ore, called cinnabar, is found chiefly in Austria, Spain, and California. It is noteworthy that the greatest American supply of mercury should have been discovered in California during the gold excitement at the very time and place it was most needed. Otherwise the miners would have been at the inconvenience and expense of obtaining mercury from far away Spain. When cinnabar is roasted to a temperature of 357.25 deg. F., the mercury rises in a vapor and is caught and condensed. Ordinary mercury, or quicksilver, is a dense liquid, 13.6 times as heavy as water. It is sensitive to change of temperature and is much used in the construction of thermometers. It freezes at--39.5 deg. F. The union of mercury and any one of several metals is called an amalgam. Placer miners nail slats across their troughs or sluices, above which they pour a little mercury. The rolling grains of gold are heavy and are caught by the mercury, forming a gold amalgam from which the mercury is separated by heat and used again. Tin amalgam is used extensively in coating the backs of mirrors. Mercury is used in the manufacture of the explosive substances of gun caps. In corrosive sublimate mercury is a rank poison. Calomel is a preparation of mercury much used in medicine. Mercury, taken in excess, remains in the system, enters the bones, and rots them. In the Austrian cinnabar mines the extreme limit of life is six years. It is said the bones of the skeletons of the miners are so loaded with mercury that quicksilver can be shaken from them. One of the most noted uses of mercury is its employment in the making of barometers. Under ordinary conditions, a thirty-inch column of mercury at the sea level is about as heavy as a similar column of air extending to the upper limits of the atmosphere. Producers put up mercury for sale usually in flasks of seventy-six and one half pounds. About 100,000 flasks are produced yearly, of which, roughly speaking, Spain furnishes a half, the United States a fourth, Austria and Italy the remainder. See Placer Mining ; Barometer
Mercury the planet nearest the sun
Aiton's Encyclopedia (1910)
the planet nearest the sun. From its brightness and quick way of shifting its position, the Greeks gave this planet the appropriate name of Mercury, the winged messenger of the gods. It is so near the sun that it appears as an evening or as a morning star . As a morning star it is seen to better advantage in March and April. It is a brilliant evening star in September and October. Mercury is the swiftest, the smallest, and the lightest of the planets. It has no satellites. It rotates once in eighty-eight days, the length of time required to pass around the sun; that is, a rotation for each revolution. It occasionally passes between the earth and the sun. A transit occurred in 1894, and another in 1907. See Saturn
Mercury the son of Jupiter and Maia
Aiton's Encyclopedia (1910)
the son of Jupiter and Maia. In Roman mythology he is the messenger of Jupiter. He is represented usually as an active young man wearing a winged hat and a pair of winged sandals. Mercury was a divinity of many natures. He was the god of darkness; hence the protecting divinity of thieves. He was by turns the god of agriculture, of science, and of commerce. He was also the patron of art and the protector of the herdsman, the traveler, and the athlete. Mercury was charged with conveying the shades of the departed to Hades. His Greek counterpart is Hermes.
Mercury Or quicksilver
An Encyclopaedia of Occultism (1920)
Or quicksilver. A metal which has been known of for many centuries, and which has played an important part in the history of alchemy. In its refined state it forms a coherent, very mobile liquid. The early alchemists believed that nature formed all metals of mercury, and that it is a living and feminine principle. It went through many processes, and the metal evolved was pure or impure according to the locality of its production.
What Has Changed in the Last Century
Aiton's 1910 claim that the planet "rotates once in eighty-eight days" stood until 1965, when radar at Arecibo showed Mercury turns three times on its axis for every two orbits, a 59-day spin; NASA's Mariner 10 flew past in 1974-75 and MESSENGER orbited from 2011 to 2015, mapping the whole planet and confirming water ice in polar craters. The metal has fared worse: mass poisonings at Minamata, Japan, from the 1950s onward made mercury a byword for industrial toxicity, and the 2013 Minamata Convention, in force since 2017, phases out mercury thermometers, batteries and mining. The great mines the entry names are shut, Almaden in Spain in 2002 and Idrija (then Austrian, now Slovenian) in the 1990s, with China now the main producer. Only the mythological Mercury is untouched: the winged messenger, patron of thieves and guide of the dead, reads exactly as it did in 1910.
Written for this edition, 2026.