m 



great intensity, and the igneous rocks then driven up through the strata 

 proved the force with which they acted ; a fine example of which may be 

 observed iu the coal field at Clee Hill, in Sbropshiro. These "faults" 

 are very numerous, and the coal beds were downcast or upcast according 

 to the circumstances of each. These "faults," in many cases, brought 

 the coal to the surface, otherwise we should never have been able 

 to get at it. The denudation iu the valleys consequent also upon the 

 volcanic disturbances, by washing away the upper rocks, often brought 

 us nearer the coal measures. Sometimes, indeed, the coal itself was wa.shed 

 away, as was the case probably in this county. A great part of Hereford- 

 shire may at one time have been covered by the carboniferous rocks and the 

 coal measures ; but the denudation caused by the great volcanic disturbances 

 which threw up the trap rocks of the Malvern hills washed them all away, 

 and left the still older rocks, the Old Red Sandstone, at the surface. There 

 are several varieties of coal. 1. The bituminous or caking coal, like the New- 

 castle, composed of bitumen, charcoal, and a little earthy matter. 2. The 

 anthracite or stone coal, like most of the Welsh coal, which is almost 

 plumbago itself, and emits no smoke. 3. The lignite. 4. The cannel ; and 

 .5. The culm or slaty coal. We must remember also that the diamond is 

 supposed to be crystallized carbon, or coal in its purest form. Amber and 

 jet are also forms of coal. The best coal was always the blackest, that is, 

 composed more purely of bitumen .and carbon. Besides the coal of the true 

 carboniferous series, there was undoubtedly coal in other formations, as in 

 lias, oolite, &c. ; but it was impure in quality and generally small in quantity ; 

 and there were also extensive deposits of tertiary coal in Germany, Prussia, 

 North America, Australia, and New Zealand. 



With reference to the origin of coal it was composed, as they all knew, 

 of vegetable matter under a peculiar chemical condition, from the combined 

 action of heat, submersion, and of great and long continued pressure. The 

 heat was not necessarily tropical, but the warm, moist heat of a climate like 

 the Brazils. The plants were mostly of a succulent nature and of a peculiar 

 character. They were Monoeotyledonous plants, or Endogens, and so much 

 changed and compressed that generally it was very difficult to get good, or 

 complete specimens. There were numerous tree ierns—Pecopteris, Odontopteris, 

 Nenropteris, &c. — the Lepidodendrons, trees partaking of the character of pines 

 and club mosses, the beautifully-marked i'igUlmia, and their numerous roots, 

 (called Stigmaria), Catamites, Pines and Palms, &c. The trees now so numerous 

 on the earth had then no existence, and those of the coal formations in them- 

 selves pointed out a peculiar atmosphere and a high temperature. The chief 

 constituent element of plants, as they knew, was carbon, which either pre- 

 viously existed, or was formed by vegetation from the simple elements of 

 the atmosphere, and the time it must have required to form such enormous 

 coal-fields was almost inconceivable. Much carbon must of course have been 

 evolved during the period. Heat, pressure, and submersion continued fo» 



