INDUSTRIAL STATISTICS. 



615 



factures, it is not at all improbable that the demand will be 

 considerably increased within the next decade or two ; so 

 that the period at which the anthracite fields will have be- 

 come practically exhausted will be materially shortened. A 

 production of 100,000,000 tons/which is about the annual 

 output of the coal-fields of Great Britain, would suffice to 

 exhaust our anthracite in the brief space of 45 years; though 

 the rapid development of the enormous deposits of bitumi- 

 nous coal in various parts of the country, and the exhaustless 

 supplies of this form of mineral fuel that are available in 

 nearly all parts of the country, render it scarcely probable 

 that the consumption of our anthracite will ever reach these 

 figures. It is well, nevertheless, that the popular notion that 

 our anthracite supply is practically exhaustless should be dis- 

 tinctly understood to be a most mistaken one ; and having 

 recognized this unpleasant fact, it will behoove our mine- 

 owners and operators to devise and introduce such improve- 

 ments in the manner of mining coal as shall reduce the pres- 

 ent large percentage of loss by waste to a more reasonable 

 amount. 



PRECIOUS METALS. 



The Engineering and Mining Journal, from the most re- 

 liable data in its possession, estimates the production of pre- 



