COPPER 



1572 



COPPER 



of Irish parentage, and studied under Peter 

 Pelharn, a \vrll-knmvn painter and engraver. 

 Copley gained a reputation by painting por- 

 traits of the aristocrats of colonial society, 

 many of which are highly prized by their 

 descendants of to-day because of their rich 

 coloring and dignified and distinguished treat- 

 ment. His portrait of Mrs. Thomas Boylston, 

 in the Memorial Hall of Harvard University, 

 and that of Mary Storer, in the Metropolitan 

 Museum of New York, represent the highest 

 types of portraiture. After 1775 he lived in 

 London, where he began a series of celebrated 

 historical paintings. Among these are the 

 Death oj Lord Chatham and the Repulse of 

 the Spanish Batteries at Gibraltar. In 1783 

 Copley was elected to the Royal Academy. 



COPPER, hop' cr. Many centuries ago the 

 Greeks and Romans obtained a red metal 

 from what is now the. Island of Cyprus in the 

 Mediterranean Sea. The Romans called this 

 metal cyprium, a word derived from Kypros, 

 the Greek name of the island. In later Latin 

 the word became cuprum, and the English 

 name for the metal is only another variation 

 of the same word. Almost everyone is famil- 

 iar with copper in some form or another. It 

 is used for the bottoms of wash boilers, for 

 tea kettles, and various other household uten- 

 sils. Copper wire is a common article of com- 

 merce, and copper nails and tacks are occa- 

 sionally seen. 



Copper is one of the metals most exten- 

 sively used in the arts. It is about nine times 

 heavier than water, melts at 2,000 F., and 

 when cold can be drawn into fine wire and 

 rolled into very thin sheets. It is more elastic 

 than any other metal except steel, and ranks 

 next to silver as a conductor of electricity. 

 It remains bright in dry air and pure water, 

 but when exposed to damp air it turns a 

 reddish-brown, owing to the formation of an 

 oxide, and long exposure to such an atmos- 

 phere causes the formation of a green sub- 

 stance commonly known as verdigris. Copper 

 articles found in the tombs of the ancient 

 Egyptians are covered with verdigris, and it 

 gives them a very ancient appearance. The 

 same effect can be produced in a few hours 

 by the use of acids, and unscrupulous dealers 

 often impose upon tourists as objects of great 

 antiquity articles of modern make that have 

 been subjected to this treatment. 



Uses of Copper. Besides those already men- 

 tioned, there are many other uses to which 

 copper is put. It forms a part of many alloys, 



as brass, gun metal, bell metal and various 

 other bronzes. It is used by all nations in 

 making an alloy for small coins, like the 

 American and the Canadian cent, and a small 

 portion is added to silver in making silver 

 coins. It is extensively used in the manu- 

 facture of electrical machinery and apparatus, 

 and hundreds of thousands of miles of copper 

 wire are in use for carrying electric current, 

 for light, power and telephone and telegraph 

 systems. The trolley wires on street car lines 

 are copper. It is occasionally used for cov- 

 ering roofs, and is very generally employed 

 in sheathing the bottoms of ships used on 

 the ocean, because salt water will not corrode 

 it. It is also very essential in making casings 

 for ammunition for the great guns used in 

 modern warfare. 



Copper Ores. Copper ores are widely dis- 

 tributed, being found in North America, nearly 

 all countries of Europe, in Japan, Africa, Aus- 

 tralia and South America, where there are 

 extensive mines in Chile. In Canada, large 



Arizona 

 382 



Montana 



Michigan 

 181 



'Figures Represent Millions of Pounds 



COPPER PRODUCTION 



The figures represent an average annual pro- 

 duction covering five years. 



deposits of copper ore are found in British 

 Columbia; at Sudbury, Ontario, where it is 

 combined with nickel; and in and about 

 Sherbrooke, Quebec. The Canadian output is 

 about 75,000,000 pounds yearly. In the United 

 States is produced more than half of the 

 world's supply. It is found in Keweenaw Pen- 

 insula, Mich., in and around Butte and Ana- 

 conda, Mont., in Arizona and Utah, and in 

 small ' quantities in a number of other states 

 and in Alaska. Contrary to very general be- 

 lief, Michigan does not lead in copper pro- 

 duction, as it once did, but that state produces 

 the best quality of the metal. Michigan has 

 been succeeded as the greatest producer by 

 Montana, and in turn Montana has fallen 

 behind Arizona (see diagram). 



