NEW YORK ACADEMY OF SCIENCES 633 



compares with it. In this connection it may be also remarked 

 that there is no more interesting chapter in the history of civil- 

 ization than that which concerns itself with the use of the met- 

 als and with the development of methods for their extraction 

 from their ores. Primitive man was naturally limited to those 

 which he found in the native state. They are but few, viz., 

 gold in wide but sparse distribution in gravels; copper in occa- 

 sional masses along the outcrops of veins, in which far the 

 greater part of the metal is combined with oxygen or sulphur; 

 copper again, in porous rocks, as in the altogether exceptional 

 case of the Lake Superior mines ; iron in an occasional meteorite ; 

 which, if its fall had been observed, was considered to be the 

 image of a god, descended from the skies; 1 silver in occasional 

 nuggets with the more common ones of gold; and possibly a 

 rare bit of platinum. Besides these no other metal can have 

 been known, because all the rest and all of those mentioned, 

 when locked up in their ores, give in the physical properties 

 of the latter but the slightest suggestion of their presence. 

 Chance discoveries must have first revealed the possibilities 

 of producing iron from its ore — really a very simple process 

 when small quantities are involved; of making bronze from 

 the ores of copper and tin; of making brass with the ores of 

 copper and zinc ; of reducing copper and lead from their natural 

 compounds; and of freeing silver from its chief associate, lead. 

 All of these processes were extensively practised under the 

 Chinese, Phenicians, Greeks, Romans and other ancient peoples. 



As the need of weapons in war, the advantages of metallic 

 currency, and the want of household utensils became felt, and 

 as the minerals which yield the metals became recognized as 

 such, the art of mining grew to be something more than the 

 digging and washing of gravels; and in the long course of time 

 developed into its present stage as one of the most difficult 

 branches of engineering. Chemistry raised metallurgical pro- 

 cesses from the art of obtaining some of a metal from its ore, 

 to the art of obtaining almost all of it and of accounting for what 

 escaped. It is, in fact, in this scientific accounting for every- 



1 As in the case of Diana of the Ephesians and the deity of the 

 Carthaginians. 



