CU ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



Lie sources from "which to give an estimate. It is confidently 

 asserted, however, that the combination of last year between 

 the great mining and carrying companies to restrict and ap- 

 portion the output of anthracite coal had a favorable effect 

 upon the bituminous trade, which would otherwise have suf- 

 fered a considerable falling-off of production by reason of the 

 continued depression of manufacturing industries and high 

 rates of transportation. From all the facts at our disposal, 

 we infer that the production of bituminous coal during the 

 past year will be found not to have varied notably from that 

 of 187728,000,000 tons, but rather under than over this 

 figure. 



OUR SUPPLY OF ANTHRACITE AND ITS DURATION. 



By the courtesy of Mr. R. P. Rothwell, Mining Engineer, 

 and the editor of the Engineering and Mining Journal, we 

 are enabled to present in the Record, from a forthcoming 

 historical treatise on the Anthracite Coal-fields of Pennsyl- 

 vania, the subjoined tabulation, which we believe is entitled 

 to be considered as a closer approximation to the actual 

 facts regarding the anthracite coal supply and its duration 

 than any previous- statements that have appeared. 



The following figures, which may be looked upon as being 

 as strictly reliable as the nature of the subject will permit, the 

 estimates of average thickness of coal in the several regions 

 and the quantities of the mineral being carefully deduced 

 from extensive practical observation and study, are interest- 

 ing and instructive in several ways. They show, in the first 

 place, most glaringly the remarkable crudity and wasteful- 

 ness of the existing methods of getting coal, the percent- 

 age of waste even in the most favored region reaching: at the 

 present time as high as 50 per cent, of the amount actually 

 marketed; and they indicate that the amount of anthracite 

 actually available for the future is much less than has gen- 

 erally been supposed even by those well informed on the 

 subject. At the present rate of consumption say about 

 25,000,000 tons annually and allowing the same proportion 

 of waste that occurs in present mining practice, the whole 

 available supply of the anthracite region will be exhausted 

 in 180 years; but as the rate of consumption must surely in- 

 crease in the future, to keep pace with the growt.li of maim- 



