MULL. GEOLOGY. 565 



With respect to composition, these strata are so similar 

 to those of Inch Kenneth that I need not repeat the 

 description. They are however seldom very acces- 

 sible, as they lie high in the cliffs, and are much over- 

 whelmed by the trap and rubbish above them. The 

 sandstones contain in some places alternate beds of lime- 

 stone ; more perhaps than I noticed, since great calcareous 

 infiltrations and stalactites may be found in the cavities 

 which lie under them ; but this, as is well known, may 

 arise from the calcareous particles in the rock. They 

 terminate by sinking under the trap or the sea, at the 

 point where the primary strata disappear. 



The small quantity of coal which has hitherto been 

 discovered in Mull is limited to two spots. The least 

 remarkable of these is a thin stratum found under the 

 trap at Ardtun ; too insignificant to be of any value in 

 an economical view, and offering no interest, in a geolo- 

 gical way, different from that of similar strata in corre- 

 sponding situations. The next is a bed of more consi- 

 derable dimensions, attaining a thickness of nearly three 

 feet. It is situated near Carsaig, in the strata already 

 described. Different attempts have been made to work 

 this coal ; since the entire want or great scarcity of peat 

 in many of the smaller islands, and the inconvenience and 

 expense of making it in all, at a time of the year when the 

 operations of agriculture require much attention, render it 

 both expensive and inconvenient; often indeed limiting 

 the fuel of a Highland family to a very insufficient allow- 

 ance. These attempts have however been successively 

 abandoned shortly after they were undertaken ; and it is 

 not now possible to procure any distinct information 

 respecting the cause, as neither the undertakers nor those 

 who were employed in the work are at present accessible. 

 It is probable that here, as in Sky, the difficulties have 

 arisen from the interference of the trap. The analogy 

 between the two cases is such as to render unnecessary 

 any further details respecting this coal, which evidently 



