696 



GEOLOGY. 



Great Britain. Near which furnace the author discovered many new coal-mines, ten 

 yards thick, and iron-mines underneath, which coal-works being brought into perfection, 

 the author was by force thrown out of them, and the bellows of his new furnace and inven 

 tion by riotous persons cut in pieces, to his no small prejudice, and loss of his invention of 

 making iron with pit-coal." He informs us, further on, that this had been " of late a 

 mighty woodland country ; " and proceeds, " NOAV if the coals and ironstone so abounding 

 were made right use of, we need not want iron as we do, for very many measures of iron 

 stone are placed together under the great ten yards' thickness of coal, and upon another 

 thickness of coal two yards thick, not yet mentioned, called the bottom coal or heathern 

 coal, as if God had decreed the time when and how these smiths should be supplied, and 

 this island also, with iron ; and most especially that this coal and ironstone should give 

 the first and last occasion for the invention of making iron with pit- coal, no place being 

 so fit for the invention to be perfected in as this country for the general good, whose 

 lands did formerly abound in forests, chases, parks, and woods, but exhausted in these 

 parts." Many subsequent attempts with furnaces supplied with air from leathern 

 bellows, worked by oxen, horses, or human labour, were failures, for additional resources 

 from mechanical powers were needed before the blast could be rendered sufficiently 

 powerful to enable pit-coal to be applied to the smelting of iron. The required assistance 

 was at length provided in the steam engine, improved and perfected within a few miles 

 of one of the great coal and ironstone districts. 



The beds of coal in a coal-field, though of a considerable number, are far less numerous 

 than the alternating strata of sandstone, and shale, called rock measures, and far less in 

 the aggregate thickness. At Anzin, near Valenciennes, a pit less than 100 yards deep 

 passes through 50 layers of coal, small and great ; at Liege 61 have been ascertained ; 

 the single mountain of Duttweiber, near Saarbruck, includes 32 ; at Newcastle the 

 Killingworth pit, within 230 yards, traverses 25. The total' thickness of the coal in the 

 English and Scottish fields is stated to be from 50 to 60 feet, divided into 20 or more beds, 

 which vary in thickness from a few inches to six feet, and alternate with from 20 to 100 

 times as great a quantity of rock measures. Mr. W. Forster, in the following table, 

 represents the alternations of the coal and rock measures in the Newcastle district, with 

 the thickness of each : 



yds. ft. in. yds. ft. in. 



yds. ft. in. yds. ft. in. 

 Brown post, or grindstone sill 24 

 Coal . 006 



Rock measures - - 10 



Coal - - 008 



Rock measures - - 22 



Coal ... 006 



Rock measures - 15 2 6 



Coal - 010 



Rock measures - 1 1 1 



Coal . . 006 



Rock measures - - 7 1 



Coal ... 008 



Rock measures - - 6 1 



Coal . 008 



Rock measures - - 19 1 



Coal 1 



Rock measures - - 16 



Coal (High Main) - . 200 



Rock measures - - 1 1 



Coal (metal coal) - 017 



Rock measures . - 6 



Rock measures 



Coal (stone coal) - 



Rock measures 



Coal (yard coal) - 



Rock measures 



Coal 



Rock measures 



Coal (Bensham) - 



Rock measures 



Coal 



Rock measures 



Coal 



Rock measures 



Coal 



Rock measures 



Coal (Low Main) - 



Rock measures 



Coal 



Rock measures 



Coal 



Rock measures 



- 10 1 2 



- 19 7 



- 7 1 



- 18 11 



- 26 6 



- 9 1 10 



-110 



- 9 2 9 



- 27 



- 15 



- 12 O 



1 2 



1 



006 



1 3 



1 6 



1 2 



009 



206 



1 6 



006 



