Page:The American Cyclopædia (1879) Volume V.djvu/317

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COPAL COPE 313 Another variety of the copal tree is found on the coast of Guinea, where lumps of the resin are gathered from the sands by the negroes. Copal is of various colors, from a pale yellow hue to a dark brown, and of different degrees of transparency. It often includes insects and animal remains. It is harder than other gums, breaks with a conchoidal fracture, and has nei- ther odor nor taste. An excellent and durable varnish is prepared from it. It melts with the heat of a spirit lamp, giving out an oily sub- stance, and becoming deeper in color until it is converted into char- coal. Copal is not eas- ily soluble in alcohol, the greater part merely swelling up and soften- ing ; but pulverized and then dried at a moderate heat, it dissolves in alco- hol of 96 per cent. Cam- phor first dissolved in the alcohol increases its pow- er of taking up the co- pal. It is much more soluble in ether, and the solution may be diluted with alcohol without the copal precipitating. Dif- ferent kinds of copal are differently affected . by ether ; some dissolve readily, others with great difficulty. Var- nishes of different qualities may be thus ob- tained by the same solvent. After ether, some of the volatile oils are the best solvents of copal, as the oils of rosemary, lavender, and spruce. The oils of petroleum and turpentine have little action on crude copal. When fused, it dissolves more easily, but produces inferior qualities of varnish. Its composition, according to Dr. Ure, is carbon 79 '87, hydrogen 9, oxygen 11-1 ; be- ing of hydrogen 7'6 in excess above the quan- tity necessary to form water with the oxygen. An excellent recipe for varnish is the following given by Bottger : 1 part of camphor is dis- solved in 12 parts of ether ; 4 of copal are then added, and allowed to swell in it, when 4 parts of anhydrous alcohol and ^ part of rectified oil of turpentine are added. It is stated by Dr. Wight that on the Malabar coast a variety of this resin, called piney dammar, is made into candles which diffuse an agreeable fragrance, give a clear light with little smoke, and con- sume the wick without requiring snuffing. A fossil copal is described in the books of min- eralogy, which resembles the resin in its hard- ness, color, lustre, transparency, and difficult solubility in alcohol. It is found in the blue clay near London, and is called Highgate resin ; and also in flattened drops on calc spar on the walls of a trap dike at an old lead mine in Northumberland. ' A similar fossil has been also obtained in the East Indies. The compo- sition of the mineral is carbon 85*41, hydro- gen 11-78, oxygen 2-67, ashes 0-136. COPAN, a small town of Honduras, Central America, in the department of Gracias, 120 m. W. by N. of Comayagua, on a river of the same name, an affluent of the Motagua. It gives its name to the wonderful ruins in its vicinity, the remains of an ancient city, which cover a densely wooded tract more than 2 m. in length along the banks of the stream. A Fallen Idol at Copan. Among them are the walls of a vast building, 624 ft. long, supposed to have been a temple, a plaza paved with well squared stones, a tower or terrace with a grand stairway of many steps descending to the river, colossal monolithic statues elaborately carved, and other sculptures. These ruins excited the wonder of the Spanish conquerors, who sought in vain to learn something of their origin from the natives. They were described with great accuracy in 1576 by the licentiate Palacios. A full account of them is given in Stephens's "Central America." (See AMERICAN ANTI- QUITIES.) COPARTNERSHIP. See PARTNERSHIP. COPE, Charles West, an English painter, born in Leeds in 1811. He is the son of an artist, studied in the royal academy, and in 1831 ex- hibited his first picture, the " Holy Family," which was purchased by Mr. Beckford. In 1843 his cartoon of the "First Trial by Jury " gained a prize of 300 in the Westminster hall competition ; and in the succeeding year he obtained a commission to paint one of the six frescoes for the new house of lords. In 1844 he was elected an associate, and in 1848 a member of the royal academy. He also re- ceived commissions to execute additional de- signs for the new palace, illustrative of inci- dents in the history of England. His eight frescoes in the peer's corridor illustrate the historical incidents of the reign of Charles I.