Page:Collier's New Encyclopedia v. 06.djvu/105

LEFT MAGIC 79 MAGNESITE their name was applied to anyone cele- brated for wisdom; hence, the wise men of the East who came to see Jesus are pimply called magi. MAGIC, the art or pretended art of putting in action the power of spirits; the science or art of producing preter- natural effects by the medium of super- natural means, or the aid of departed spirits, or the occult powers of nature. A belief in magic is to be reckoned among the earliest growths of human thought. The practice of magic had its origin in the belief in an objective connection be- tween two things — a man and a rude drawing or image of him, or two events — as between the birth of a child and the rising or setting of a particular star, when, in truth, the connection could only be subjective. Black magic : Magic proper, or that di- vision of it which in former times fell into the hands of unofficial persons, or was practiced with malefic intentions. Celestial magic : A supposed supernatural power which gave to spirits a kind of dominion over the planets, and to the planets an influence over man. Natural magic : The art of applying natural causes to produce effects apparently supernatu- ral. Superstitious or goetic magic: The invocation of devils or demons involving the supposition of some tacit or express agreement between them and human be- ings. White magic: (a) Magic practiced for the benefit of others, (b) The art of performing tricks and exhibiting illusions by aid of apparatus, excluding feats of dexterity in which there is no deception, together with the performance of such automaton figures as are actuated in a secret and mysterious manner. MAGIC CIBCLE, a circle invented by Franklin, founded on the same principles and possessing similar properties with the magic square of squares. MAGIC LANTERN, an instrument by which the images of objects, usually, but not always, transparent, and paint- ings or diagrams drawn on glass are exhibited, considerably magnified, on a wall or screen. MAGIC SQUARE, a square figure formed by a series of numbers in math- ematical proportion, so disposed in paral- lel and equal rows that the sum of the numbers in each row or line, taken per- pendicularly, horizontally, or diagonally, are equal. MAGNA CHARTA (kar'ta), or MAG- NA CARTA, originally the Great Char- ter of the liberties of England and sub- sequently of the whole civilized world (Magna Charta Libertatum), signed and sealed by King John at the deniand of his barons, at Runnymede, on June 15, 1215. It was several times confirmed by his successors. MAGNA GR.fflCIA (gre'shia), or MAJOR GR^CIA, in ancient history, the name applied by Greek writers to their colonies formed on the S. shores of Italy, Cumae having by general consent the precedence in point of antiquity, though the date of its foundation 1050 B. C, is not to be relied on. There is much un- certainty as to the precise dates of the various settlements; but the greater number of them were probably made between 735 B. c. and 685 B. c; Sybaris, 720 B. c, and Crotona, 710 B. c, the two most powerful cities, were founded by the Achaeans. Tarentum, a Spartan col- ony, was established about 708 B. c; Metapontum by the Achaeans, 700-680 B. C; and Locris by the Locrians, about 700 B. c. MAGNESIA (-ne'shia), in mineralogy, the same as periclase. Used as a drug, if administered in small doses, magnesia acts as an antacid; if in quantity beyond what is necessary to neutralize acids in the stomach, it passes undigested into the intestines, and may form concretions. The salts of magnesia are purgatives. It is given as a lithontriptic, from its power of dissolving uric acid, and in gouty diseases. MAGNESIAN LIMESTONE, a lime- stone composed of carbonate of lime and carbonate of magnesia, the proportion of the latter sometimes being nearly 50 per cent. It effervesces much more slowly with acids than common limestone (car- bonate of lime). It is sometimes earthy, sometimes hard and compact. One variety of it is Dolomite (g. v.). MAGNESITE, a widely occurring mineral, consisting of magnesium car- bonate, MgCOs. It is mined in California, British Columbia, New Jersey, New York, Washington, Quebec, India, Austria, and Greece. It occurs in three forms — crys- talline, massive, and earthy, the two latter being white in color and frequently mixed with other magnesium salts. Its princi- pal use is in the manufacture of refrac- tory linings for furnaces and retorts, and for this purpose it is of great value in the cement and metallurgical industries. It is also used in the preparation of Epsom salts (magnesium sulphate) and other salts of magnesium. A strong cement is made by mixing calcined mag- nesite with chloride of magnesium. Other uses are in the manufacture of paper and pigments and for heat insulation.