THE LIMITS OF OUR COAL SUPPLY. 223 



below the surface, and even beyond this limit ; but with this latter 

 quantity it is scarcely necessary that we should concern ourselves." 

 I shall presently show reasons for believing that the time may ulti- 

 mately arrive when we shall concern ourselves with this deep coal, 

 and actually get it ; while, on the other hand, that remote epoch will 

 be preceded by another period of practical approximate exhaustion 

 of British coal supply, which is likely to arrive long before we reach 

 a working depth of 4000 feet. 



The Royal Commissioners estimate that within the limits of 4000 

 feet we have hundreds of square miles of attainable coal capable of 

 yielding, after deducting 40 per cent, for loss in getting, etc., 146,480 

 millions of tons ; or, if we take this with Mr. Hull's deduction of 

 one twentieth for seams under two feet in thickness, there remains 

 139,000 millions of tons, which, at present rate of consumption, 

 would last about 1200 years. But the rate of consumption is an- 

 nually increasing, not merely on account of increasing population, 

 but also from the fact that mechanical inventions are perpetually 

 superseding hand labor, and the source of power in such cases is 

 usually derived from coal. This consideration induced Professor 

 Jevoiis, in 1865, to estimate that between 1861 and 1871 the consump- 

 tion would increase from 83,500,000 tons to 118,000,000 tons. Mr. 

 Hunt's official return for 1871 shows that this estimate was a close 

 approximation to the truth, the actual total for 1871 having been 

 117,352,028 tons. At this rate of an arithmetical increase of three 

 and a half tons per annum, 139,000 millions of tons would last but 

 250 years. Mr. Hull, taking the actual increase at three millions of 

 tons per annum, extends it to 276 years. Hitherto the annual in- 

 crease has followed a geometrical rather than arithmetical progress, 

 and those who anticipate a continuance of this allow us a much 

 shorter lease of our coal treasures. Mr. Price Williams maintain.* 

 that the increase will proceed in a diminishing ratio like that of the 

 increase of population ; and upon this basis he has calculated that 

 the annual consumption will amount to 274 millions of tons a hundred 

 years hence, and the whole available stock of coal will last about 360 

 years. 



The latest returns show, for 1872, an output of 123,546,758 tons, 

 which, compared with 1871, gives a rate of increase of more than 

 double the estimate of Mr. Hull, and indicate that prices have not yet 

 risen sufficiently to check the geometrical rate of increase.* Mr. 

 Hull very justly points out the omission in those estimates which do 

 not " take into account the diminishing ratio at which coal must be 

 consumed when it becomes scarcer and more expensive ;" but, on 

 the other hand, he omits the opposite influence of increasing prices 

 on production, which has been strikingly illustrated by the extraor- 

 dinary number of new coal-mining enterprises that have been 

 launched during the last six months. If we continue as we are now 

 proceeding, a practical and permanent coal famine will be upon us 

 within the lifetime of many of the present generation. By such a 

 famine, I do not mean an actual exhaustion of our coal seams (which 

 will never be effected), but such a scarcity and rise of prices as shall 

 annihilate the most voracious of our coal-consuming industries, those 



* From 1870 to 18SO the amount has risen from 110.431,192 to 146,818,022 tons per 

 annum, un average increase of 3,638,743 tons per annum. 



