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acceleration in I860, which was the year when the new French 
Tariff came into operation. That commercial arrangement, and 
the consequent development of our trade, — which was greatly 
assisted by the International Exhibition of 1862, — has led to a 
steady increase in the home consumption of coal. This it is 
shown is not dependent upon the increase of population : it 
is evidently due to the activity of all our manufacturing 
industries. 
5. May we expect that this annual increase will continue 
in some such ratio as that observed during the last five years ? 
Let us consider for a moment what is the rate of increase at 
present. Mr. W. Stanley Jevons, in his excellent book on 
“ The Coal Question/' who has examined this point with great 
care, says, “We of course regard not the average annual 
arithmetical increase of coal consumption between 1854 and 
1863, which is 2,403,424 tons, but the average ratio or rate 
per cent, of increase, which is found by logarithmic calculations 
to be 3’ 26 per cent. That is to say, the consumption of each 
year, one with another, exceeds that of the previous as 103*26 
exceeds 100." Assuming this rate of increase, 3^ percent, per 
annum, to continue, we should in the year 1 900 draw from our 
rocks, more than 300 millions of tons, and in 1950 nearly 2,000 
millions. About 300,000 miners are now employed in raising 
rather more than 92 millions of coals ; therefore more than 
eight million miners would be necessary to raise the quantity 
estimated as the produce of 1950. One third of the present 
population of Great Britain would be coal-miners. “If our 
consumption of coal continue to multiply for 110 years at the 
same rate as hitherto, the total amount of coal consumed 
in the interval will be 100,000 millions of tons" (Jevons). 
Mr. Hull tells us that he estimates the available coal in 
Britain at 83,000 millions of tons, within a depth of 4,000 
feet ; therefore in one century from the present time we shall, 
according to this, exhaust all the coal in our present work- 
ings, and all the coal seams which may be found at a 
depth of 1,500 feet below the deepest working in the kingdom. 
The assumption upon which this estimate is based, is absurd 
from every point of view. Such a continued increase as 
that which has taken place during the last five years, cannot 
continue for the succeeding ten years. 
The increase in our exportation of coal has been during that 
period but very trifling. The price of coal is advancing, and 
with higher prices we must expect our exports to fall off. 
Although there is an extension of our pig-iron manufacture, 
there does not appear to be a corresponding enlargement of 
the trade in merchant iron, or of such manufactures as are 
required by the engineer. Large pumping-engines for use in 
