WILLIAM SIEMENS, F.R.S. 131 



the introduction of economical processes in the application of fuel. 

 In the case of the production of power, the economy effected in 

 onr best engines within the last 20 years exceeds 50 per cent., and 

 an equally important saving has probably been realised in the 

 production of iron and steel within the same period, as may be 

 gathered from the fact that a ton of steel rails can now be pro- 

 duced from the ore with an expenditure not exceeding 55 cwt. of 

 raw coal, whereas a ton of iron rails, 20 years ago, involved an 

 expenditure exceeding 100 cwt. According to Dr. Percy, one 

 large works consumed, in 1859, from 5 to (5 tons of coal per ton of 

 rails. Statistics are unfortunately wanting to guide us respecting 

 these important questions. 



Considering the large margin for further improvement in almost 

 every application of fuel, which can be shown upon theoretical 

 grounds to exist, it seems not unreasonable to conclude that the 

 ratio of increase of population and of output of manufactured 

 goods will be nearly balanced, for many years to come, by the 

 further introduction of economical processes, and that our annual 

 production of coal will remain substantially the same within that 

 period, which under those circumstances will probably be a period 

 of comparatively cheap coal. 



The above-mentioned speculation leads to the further conclusion 

 that our coal supply at a workable depth will last for a period far 

 exceeding the shorter estimated period of 250 years, especially if 

 we take into account the probability of fresh discoveries, of which 

 we have had recent instances, particularly in North Staffordshire, 

 where a large area of coal and blackband ironstone is being opened 

 up, under the auspices of his Grace the Duke of Sutherland, by 

 our member, Mr. Homer. 



"Wherever coalfields are found in Great Britain, they exist, 

 generally speaking, under favourable circumstances. The deposits 

 are for the most part met with at reasonable depths, the quality of 

 the coal is unsurpassed by that of other countries, and although 

 the coal and ironstone do not occur together in all the iron-pro- 

 ducing districts, the distance from the coal to the iron is small, 

 compared with that met with in other countries, and the insular 

 position of Great Britain renders water carriage, both for internal 

 communication and for the purpose of export, more readily avail- 

 able than elsewhere. These advantages ought to decide the 



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