112 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [JuiXG 9, 



ings in the quarries. He says that the crevice or fissure where it 

 occurred was not larger than a man's fist, and so completely shut in, 

 that even water could not have found an entrance from the surface 

 until the rock was broken up by gunpowder. Mr. White did not 

 obtain the specimen himself, but is quite convinced that it was 

 discovered in the place and under the circumstances stated. 



The coal sent to me is highly bituminous, and burns readily, with 

 a bright flame. In external characters it closely resembles the com- 

 mon bituminous coal of the Scottish coal-field. "When examined 

 under the microscope, it exhibits traces both of cellular and fibrous 

 structure, sufficient to show its vegetable origin. Its occurrence in 

 this position is very remarkable*. 



Supposed organic remains. — The only indications of organic re- 

 mains that I have observed, besides the carbonaceous matter above 

 mentioned, are of a very uncertain character. On the exposed sur- 

 faces of some of the soft black rocks near Oban, markings occur like 

 those of the annelids or fucoids seen in some of the older rocks. In 

 general form they very closely resemble the Palceochorda minor of 

 M'Coy f. Their true nature is, however, uncertain ; and such rude 

 and obscure forms can have httle value in determining the age of 

 the beds. Prom the same place I also obtained a curious conical 

 body, like the fragment of an Orthoceratite, but too obscure to allow 

 me to be certain even of its organic origin. 



Stratification of the slate. — In the Easdale quarries, the slate forms 

 beds of considerable thickness, weU known to the workmen from the 

 change that takes place in the quality of the rock in passing from 

 layer to layer. The stratification is, however, very indistinctly 

 marked, and is often so obscured by the cleavage, that it may be 

 entirely overlooked without great care. The beds are disposed in 

 great rolls or undulations, of which three at least are clearly seen ; 

 but, on the whole, they dip at a high angle to the west or north- 

 west. In the rocks near Oban the stratification is more clearly 

 marked, but vsdth very great diversity both in the amount and direc- 

 tion of the dip. The beds, indeed, appear to have been so broken up 

 and crushed together as to destroy aU regularity in their position. 



* Last smnmer (July 1858) I again visited Easdale, and examined into the 

 facts in reference to this coal. The place where it occurred was pointed out by 

 the workmen who found it. It was in the fine of a very narrow crack or slip la 

 the beds, scarcely more than ^^th inch wide, but reaching to the surface. This slip 

 is nearly parallel to the cleavage, but transverse to the bedding. The coal was not 

 enclosed in the solid rock, but in soft clay. On the surface of the mass of coal 

 the vegetable structure is distinctly seen, as in the common coal from the central 

 district of Scotland, of which it seemed to be a portion. It has, of course, no 

 bearing whatever on the geological age of the slates ; but the mode of its intro- 

 duction into such a narrow fissure seems a problem of much difficulty. — J. N., 

 January 1859. 



t Sedgwick and M'Coy, ' Palaeozoic Fossils,' pi. 1 a. figs. 1 & 2. These figures 

 are very tolerable representations of a specimen in my possession. They are 

 fi*om the black slates of Skiddaw, in which Professor Sedgwick mentions the 

 occurrence of carbon (Journ. Greol. Soc. vol. iv. p. 220). The mineral character 

 of the beds thus adds to the probability that the Easdale slates belong to the 

 same period with the Skiddaw slates. 



