546 



NA TURE 



\Oct. 31, 1872 



very beautiful ; we may notice particularly the gold myrtle wreath 

 found in an Etruscm tomb a few years ajo.^ The Ejyptiani 

 also used gold for inlaying, and it was beaten into leaf and uicd 

 fir gilding as early as 2000 B.C. In the Odyssey the gilding of 

 the horns of an ox about to be sacrificed is mentioned. 



Silver, like gold, is often found native, and from several of its 

 ores the metal may be extracted by the action of heat alone. It 

 has been known from the earliest ages, and was used chiefly for 

 ornaments and embroidery. Gold was used for moaey before 

 tilver, which was first known as " white gold." The oldest silver 

 Greek coin is a coin of .45gina, and wa?, perhaps, coined in the 

 eighth century n.c. But the oldest coins in existence are the 

 electnim staters of Lydia. Electrum consists of about three parts 

 of gold to one of silver. Probably the metals were first found in 

 nature thus alloyed, and as no method of separating them was 

 th»n known, tliey were worked up together. Electrum was so 

 called froii its resemblance as regards colour to amber (iJ-VfjcrpoK), 

 which received its name from ii\6')CTco/), the sun. It will be re- 

 membered incidentally that the science of Electricity was so 

 called by Gilbert of Colchester, because the attractive force w.is 

 first observed in amber. Amber is mentioned more than once 

 by Homer. Electrum as a metal is first mentioned in the Anti- 

 gone of Sophocles. It was found naturally alloyed, as in the 

 pale gold of the Pactolus, which contains a good deal of silver ; 

 and was also made artificially. Probably all very pale gold was 

 callel electrum ; Pliny states that gold containing a fifth part of 

 silver is called electrum. In the British Museum there are many 

 coins made of this alloy. 



Copper was in use before iron. It is, as is well known, usual to 

 denote various early ages by the substances then used for domestic 

 implements. Thus we have the "age of stone," the " age of 

 iron," &c. The stone age is followed by the age of copper, this 

 bv the age of bronze, and the age of bronze by the age of iron. 

 Homer wrote in the age of copper ; the shield of Achilles is 

 made of gold, silver, tin, and copper ; the arms and implements 

 and utensils of his heroes are of copper. Mr. Gladstone has 



argued at some length that by chalcos (xaXfcoi) Homer meant 

 copper, not bronze, as it is so often rendered. Chaleos is .spoken 

 of as a cheap and common metal, while tin was very scarce and 

 rare ; and it is scarcely probable that so many things, even down 

 to the commoner utensils, could have contained ten or twelve per 

 cent, of tin. Again, Mr. Gladstone points out that Homer 

 speaks of chalcos as ipuSpot, red, a term that could not apply to 

 bronze ; and he goes so far as to say, " If chalcos be not cop- 

 per, then copper is never mentioned in Homer" {Juvenilis 

 Mundi, p. 530). At the tame time we must remember that 

 copper is very soft for cutting-instruments, and a small quantity of 

 tin hardens it ; some of the Greek bronzes only contain \ per cent, 

 of tin. Dr. Percy found in a bronze bowl of great antiquity from 

 Nineveh, copper 99'5i, tin '63. Ancient nails have been found 

 containing copper 9775, tin 2 '25 ; and Mr. Gladstone suggests 

 that, as tin is sometimes found associated with copper in nature, 

 this may account for their composition. Copper is sometimes 

 found native, sometimes in the form of ores, from which the 

 metal is easily extracted. It appears to have been both cheap 

 and plentiful at an early date. Romulus is said to have coined 

 copper ; it was also used for money by the Egyptians. Great 

 confusion exists among old writers regarding the words signifying 

 bronze and copper : Pliny clearly did not understand the differ- 

 ence between copper and bronze. The words ivs and xo^"''' 

 appear to have been applied indiscriminately both to copper and 

 to alloys of copper containing a large proportion of that metal. 

 Copper was alloyed with tin at such an early date, because cop- 

 per is soft and is unsuitable for cutting-instruments, while the 

 addition of tin hardens it. The fusing point of copper is between 

 that of gold and silver, and is far below that of iron, whde the 

 fusing point of tin is only 446' I'\ Thus the two metals could 

 be alloyed without any special metallurgical dilhculties or the 

 requirement of an inordinate temperature. Copper was first ob- 

 tained by the Romans from Cyprus, where it was very plentiful ; 

 they called it -iV Cypriitm, which became corrupted into 

 Ctipndii, from which we get our present chemical symbol fo r 



Fig. I.— Gold Washing 1 Fusion and Weighing of the Melal, from e.irly Egyptian Tomb 



copper, Cu. According to Solinus <is was found at Chalkis, in 

 Euboea, hence xa^fos, the Greek word for copper. We read of 

 " ores of ces," and of brass and bronze being dug out of mine«, 

 whereas the term brass is applied by us to an alloy composed of 

 copper and zinc, and bronze to an alloy of copper and tin. Zinc 

 as a metal was unknown to the ancients, and brass appears to 



or golden copper, was the proper name for brass, .l-'.s i ; to b } 

 always translated copper or bronze, not brass, of which latter 

 very little use appears to have been made. Among other alloys 

 of copper, the ancients possessed the celebrated .A'j' Coriitthiacum, 

 which, according to Pliny, was formed accidentally during the 

 burning of Corinth, by Mummius, n.c. 146. There were four 

 varieties of this, one of which contained equal proportions of 

 gold, silver, and copper ; the others were most probably various 

 admixtures of copper and tin. Tlie commonest kind of ancient 

 bronze contained in 100 parts, 88 parts of copper, and 12 farts 

 of tin. Two specimens of bronze from Nineveh were found by 

 Dr. Percy to contain respectively — 



99 (io 



98-89 



have been made in Pliny's time by heating together metallic 

 copper, calamine (a native carbonate of zinc), and charcoal ; tlic 

 latter reduces the cabimine, and the metallic zinc and copper then 

 combine. According to Dr. Thomas Thomson, auruhaUhum, 



The pro]iortion of copper and tin (about 10 to i) is, remarkj 

 Mr. Layard, the composition of our best modern bronze, while 

 the increase of tin in the case of the bell proves that the Assy- 

 rians were well acquainted with the increase of sonorousness pro- 

 duced by changing the ]iroporti<ins of the metals. Modern bell 

 metal contains about 80 parts of copper to 20 parts of tin. Some- 

 times a small quantity of lead was introduced by the ancients 



