Geology of England and Wales, ''^ ^c. 227 



inense manufacturing establishments, is deeply realized in 

 Great Britain.* 



Englishmen look forward, not without some anxiety, to 

 the period, when their coal mines will be exhausted. The 

 following calculation, from the work before us, shows that 

 such a time is yet quite remote. It applies, however, on- 

 ly to the great coal field of Northumberland and Durham. 

 "To form an idea, says Dr. Thomson, of the quantity 

 of coal contained in the formation called the coal meas- 

 ures, let us suppose it to extend in length from north to 

 south twenty-three miles, and that its average breadth is 

 eight miles. This makes a surface amounting to rather 

 more than l80 square miles, or 557,568,000 square yards. 

 The utmost thickness of al! the beds of coal put together 

 does not exceed forty-four feet ; but there are eleven beds 

 not workable, the thickness of each amounting only to a 

 few inches. If they be deducted, the amount of the rest 

 will be thirty six feet, or twelve yards. Perhaps five of the 

 other beds likewise should be struck ofT, as they amount 

 altogether only to six feet, and therefore at present are not 

 considered as worth working. The remainder will be ten 

 yards ; so that the whole coal in this formation amounts to 

 5,575,680,000+ cubic yards. How much of this is already 

 temoved by mining 1 do not know, but the Newcastle col- 

 lieries have been wrought for so many years to an enor- 

 mous extent, that the quantity already mined must be con- 

 siderable. I conceive the quantity of coal exported yearly 

 from this formation exceeds two millions of chaldrons, for 

 the county of Durham alone exports l~ millions. A chal- 

 dron weighs 1. 4 ton, so that 2. 8 millions of tons of coals 



* Although an unpoetic subject, its importance drew forth a stanza from 

 one of their earliest poets. 



" Had he our pits, the Persian would admire 

 No sun, but warm's devotion at our fire : 

 He'd leave the trotting whipster, and prefer 

 Our profound vulcan'bove that waggoner. 

 For wants he heat, or light, or would have store 

 Of both? 'tis here: and what can suns give more ? 

 Nay, what's the sun, but, in a different name, 

 A coal pit rampant, or a mine on flame ! 

 Then let this truth reciprocally run, 

 The sun's heaven's coalery, and coals our sun." 



t The three la«t cyphers are omitted in the original work ; which is oh* 

 viously a mistake. 



