Ixxvi PROCEEDINGS OE THE GEOLOGICAL SOCIETT. [June 1912^ 



separatel)', each one dealing with a single group of coal-areas or a 

 single branch of their enquiry. 



All the matters relating to the 'unproved' fields were put 

 into the hands of a committee of Geologists specially qualified to- 

 deal with them, who issued carefully reasoned and, on the whole, 

 extremely cautious reports on the areas entrusted to them. 



The figures issued by the Comissioners may be summarized in 

 round numbers, as follows : — 



^unions of tons^ 

 Coal available in 'proved ' fields (exposed and concealed) ... 100,000 

 Do. do. in 'unproved ' fields (concealed) 40,000 



Total 140,000 



In addition to this, about 5000 million tons were estimated as- 

 occurring below 4000 feet in the proTed coalfields. 



With regard to the probable duration of our coal resources, the 

 second Commission, like the first, althougVi it stated the facts very 

 fulh', did not commit itself to any definite opinion. The output in 

 1903, namely 230 millions of tons, was just double that taken by 

 the first Commission for 1870. This gives an annual increment of 

 3*6 million tons, or, as the Commission puts it, an increase of 2| 

 per cent, per annum in the output, and 4| per cent, per annum 

 in the exports. The Report adds : — 



' It is the general opinion of the District Commissioners tbat, owing to physical 

 considerations, it is liighly improbable that the present rate of increase of the 

 output of coal can long continue — indeed, they think that, some districts have 

 already attained their maximum output ; but that, on the other hand, tlie 

 developments in the newer coalfields will possibly increase the total output for 

 some yeai's. 



' In view of this opinion and of the exhaustiou of the shallower collieries, 

 we look forward to a time, not far distant, when the rate of increase of output 

 will be slower, to be followed by a period of stationary output, and then a 

 gradual decline.* 



The Commissioners, however, published, and in their final Eeport 

 called the attention of readers to, an elaborate series of tables 

 and curves contributed b}^ Mr. Price Williams, which state the 

 probable duration of the coal supply based upon different methods of 

 calculating the consumption. These tables give the output of coal 

 which will on certain assumptions be required to cope with the 

 increasing export and home consumption for each year from 1901 

 to 2200, and for each decade up to 2300. The estimated export of 



