452 TRANSACTIONS OF SECTION B. 
The knowledge of metallurgical testing and analysis was shown to be 
indispensable when the varying composition of commercial brands of crude 
copper and the multitudinous uses to which refined copper is put are taken into 
consideration. 
Manufacturers should never lose sight of such fundamental considerations as 
the following :— 
1. To what degree the various impurities may be eliminated during refining 
operations. 
2. To what specifications (however imperfect such specifications may be) the 
resulting changes may have to conform. 
3. To what extent impurities may mutually react to the improvement or 
detriment of the resulting material. 
The author has given special attention to the influences of oxygen and 
arsenic, whilst bismuth, lead, nickel, antimony, silicon, iron, phosphorus, 
manganese, &c., are all dealt with in turn. 
The evidence of the microscope was called largely into requisition and the 
importance of various kinds of testing was emphasised. 
