Reviews — Report of the Coal Commission. 519 



Mr. Prestwich shows that there are grounds for believing in the 

 existence of coal on the south side of the Mendips, and under adjacent 

 parts of the Bristol Channel, but at a depth of not less than 1500 to 

 2000 feet; and he mentions also a small new Coal-basin in the 

 Severn valley, near New Passage. 



In regard to the future exportation of Coal, Committee B report 

 that although a large increase has taken place since the year 1855, 

 yet this increase has merely averaged one per cent, each year, and 

 there is reason to doubt whether much further increase will take 

 place in this direction. 



The large increase which in recent years has taken place in the 

 consumption of coal has an intimate connexion with the introduc- 

 tion and extension of railways ; moreover the town-population, which 

 represents the chief coal -consuming population, is increasing in a 

 far more rapid ratio than the population of the kingdom generally ; 

 and the extension of machinery and improvements for economizing 

 labour cause the consumption of coal to be constantly increasing. 



Adopting four thousand feet as the limit of practicable depth in 

 working, excluding all beds of coal less than one foot in thickness, 

 and deducting an amount for the waste and loss incident to working 

 the coal, it is estimated that in known Coal-fields in the British 

 Isles there is an available quantity of coal equal to 90,207 millions 

 of tons, while the coal which probably exists at workable depths 

 under the Permian, New Eed Sandstone, and other superincumbent 

 strata in the United Kingdom, is estimated at 56,273 millions of 

 tons, making an aggregate quantity of 146,480 millions of tons 

 which may be reasonably expected to be available for use. From 

 careful calculations respecting the duration of this coal, taking into 

 account the increased consumption, it is estimated that this quantity 

 of coal would represent a consumption of 276 years. 



There is, however, a large amount of coal excluded from these 

 estimates, namely, that lying beneath Permian and newer strata, at 

 depths exceeding 4,000 feet. The amount at depths from 4,000 to 

 10,000 feet is estimated at 41,144 millions of tons, to which may be 

 added 7,320 millions of tons at greater depths than 4,000 feet within 

 the area of the known Coal-fields, making a total of 48,465 millions 

 of tons. It is entirely a matter of conjecture whether any or what 

 portion of this coal can ever be worked ; but the absolute exhaustion 

 of coal is a stage which will probably never be reached. 



In order to investigate the probable quantity of coal contained in 

 the known Coal-fields of the United Kingdom, the area was divided 

 into thirteen districts, which were assigned to different members, or 

 to gentlemen specially acquainted with the areas. Thus, Mr. Vivian 

 reported on the South Wales Mineral Basin westward of " Grlyn- 

 corrwg Fault," and Mr. G. T. Clark on the eastern division of the 

 South Wales Coal-field. Their reports are accompanied by elaborate 

 tables showing the calculations of the areas and quantities of coal in 

 the field. 



Mr. Dickinson reported on the quantity of coal remaining un- 

 wrought in the Coal-fields of Lancashire, Cheshire, North Wales, 



