498 SCIENCE PROGRESS. 



At the present time the annual production of gold from 

 all these sources is about ^42,000,000 per annum, or double 

 the output of seven years ago. It is greater than at any 

 previous period in history, the nearest approach to it having 

 been made in 1853, when the river gravels of California 

 and Australia were at their best. The output was then 

 estimated at ^"38,000,000. 



Of the present output, washing processes, formerly in- 

 strumental in producing by far the larger proportion of 

 the gold won, are now probably answerable for no more 

 than 30 per cent. The amalgamation of crushed vein 

 stuff, now the most important process, produces about 55 

 per cent, of the whole gold production. The two wet 

 processes, chlorination and cyanide, account for some 1 1 

 per cent, of the output, of which about two-thirds are 

 contributed by the cyanide process, and, lastly, smelting 

 perhaps produces 3 or 4 per cent, of the total. In the 

 future, as placer gravels become exhausted more and more, 

 the proportion of the output derived from them will 

 continue to fall off, and the greatest increases will certainly 

 take place in the produce from stamp battery amalgamation 

 and the cyanide process. The output from chlorination 

 and from smelting has been for some years stationary or 

 declining, and their proportion of the world's production 

 will doubtless suffer a continued though gradual reduction. 

 It is obvious that by new discoveries the whole direction 

 and progress of the art might be modified. As the old 

 deposits become exhausted the miner is compelled to go 

 deeper into the earth and the metallurgist to treat poorer 

 and more refractory ores. " Such is the vast labour ex- 

 pended on the extraction of gold. And from this descrip- 

 tion I think it is clear that gold is hard to get as it is 

 difficult to keep ; and though all men long to get it, yet 

 when they have it they find as much pain as pleasure in 

 the use of it." l 



T. K. Rose. 



1 Diodorus Siculus, book iii., chap. 12. Quoted by B. H. Brough, 

 ioc. cit. an tea. 



