SALTER — A CHRISTMAS LECTURE ON COAL. 



125 



hangings in the studio of the geologist. Who will try copies from 

 nature for this purpose ? 



Fig. 7.— Sigillaria elegans. Fig. 8.— Sigillaria Defrancii. 



Patterns of bark Sigillaria. Pattern of the markings on the bark. 



But Sigillaria is not always found lying prostrate. It is very often 

 upright, as it grew ; so many instances are known of this that it is 

 almost useless to repeat them. A stump, ten feet high, is figured in 

 Dr. Mantell's "Wonders,"* a book worthy of every young geologist's 

 ambition. Others have been noticed by Sir Charles Lyell, and a whole 

 forest of short stumps was discovered in 1838, near Chesterfield, during 

 the diggings for a railway. There were no less than forty trees — a 

 few feet apart — on this one spot. In Durham, at Newcastle, and in the 

 South Wales coal-basin, others have been found. Hugh Miller, in 

 his interesting book — "First Impressions of England and the Eng- 

 lish," (p. 233J — has described his visit to the celebrated Wolver- 

 hampton coal-forest. Here seventy-three stumps, in three tiers, 

 one over another, are closely packed : and three successive forests 

 — on the same spot — seemed to him the best way of accounting for 

 it. I think we have a better explanation; but I am not sure of that. 



But, then, these trees have roots to them ; and the discovery of these 

 roots has opened up a new chapter in the history of coal. ISTay, it 

 has deciphered that history ; for till Sir W. Logan found that every 

 coal-bed had its underclay full of roots, and till Mr. W. E. Binney, of 

 Manchester, traced these roots (which are called Stigmaria, (fig.), 

 to their connection with the tree, we never truly knew how coal was 

 formed. 



2nd Edition. — By T. Rupert Jones, Esq., Vice- Sec. Geol. Society, 1858. 



