228 



CERTAIN SAND MOUNDS OF 



the middle of the fifteenth century. Toward the close of the century, in 1494, 

 they were abandoned, but reopened early in the sixteenth century and operated 

 intermittently. According to Jervis these are among the richest copper mines of 

 Europe. The ores are sulphides. 



Another copper mine of importance is that of Ravamonte, near Agordo, in the 

 Venetian Alps, which was operated, according to Jervis {pp. cit., Vol. I, page 332), 

 so far back as the fifteenth century. The process employed there for the extraction 

 of copper is described by Haton, Percy, and Rivot. 



Percy (Metallurgy, Vol. I, page 439) says : " The process appears to be of 

 comparatively ancient date ; but I have not been able to trace its history with cer- 

 tainty. At the present time (1861) it appears to be carried on with great skill at 

 Agordo, where it is stated to have been first introduced in 1692 by a Prussian of 

 the name of Weyberg." 



The copper, according to Schnabel's Metallhiittenkunde, contains : — 



" Arsenic 



0*64 per cent 



Antimony 



. 0.04 



Lead 



. 0-20 



Silver 



. o-io 



Sulphur 



. 0-04 



We shall not occupy space with farther analyses of Italian copper, the impuri- 

 ties of which, as a product of sulphide ores, the reader is by this time in a position 

 to divine. 



Now let us consider results of analyses of copper used by Indians after contact 

 with the Whites. 



We are indebted to David Boyle, Esq., of the Canadian Institute, Toronto, for 

 a fragment of copper taken by him from a grave of the Tobacco Huron s, near that 

 place. In these graves are articles unquestionably of European origin. 



This fragment submitted to Dr. A. R. Ledoux, was analyzed and reported upon 

 as follows : — 



"Copper 

 Silver 



. 98-970 per cent 

 . 0-084 



Iron 



. 0-057 



Arsenic 



. 0-160 



Antimony 

 Nickel and cobalt 



. 0-130 

 . 0-070 



Lead . 



. 0-300 



"The sample contains no bismuth, tin or zinc. The low percentage of copper is 

 partially due to oxygen which it was impossible to remove entirely from such thin 

 samples. This copper is, as you will note, of inferior grade." 



The considerable collections of post-Columbian Indian relics of Mr. W. W. 

 Adams, of Cayuga Co., N. Y., largely made on the spot by him, contained no 

 specimens of early post-Columbian copper other than ears of copper on two kettles 

 of brass, and in one instance copper rivets joining together two sheets of brass 



