RAMBLES OF A GEOLOGIST. 261 



to an upper Liasic bed So rich is the dark-coloured tena- 

 cious argil of the Inferior Lias of Eathie, that the geologist 

 who walks over it when it is still moist with the receding 

 tide would do well to look to his footing ; the mixture of 

 soap and grease spread by the ship-carpenter on his launch- 

 slips, to facilitate the progress of his vessel seawards, is not 

 more treacherous to the tread : while the Upper Liasic de- 

 posit which rests over it is composed of a dark slaty shale, 



dark lias will be strikingly contrasted with the white lime, and form 

 rather a pretty piece of natural mosaic. 11. Coming to a simple piece of 

 machinery for removing fragments of shale and stone from the clay, we 

 examined some of the bits so rejected, and found what we had no doubt 

 were fish-scales. 12. "We have yet to notice certain long slender bodies, 

 outwardly brown, but inwardly nearly black, resembling whip-cord in 

 size. Are we to regard these as specimens of a fucus, perhaps the filum, 

 or allied to it, which is known in some places by the appropriate name of 

 sea-laces ? 13. Passing on to the office, we were shown a chop of wood that 

 had been found in the clay, and was destined for the Banff Museum. It is 

 about eighteen inches in length, and half as much in breadth ; and, although 

 evidently water- worn, yet we could count between twenty-five and thirty 

 concentric rings on one of its ends, which not only enabled us to form some 

 conjecture of its age previous to its overthrow, but also justified us in re- 

 ferring it to the coniferae of the vorwelt, or ancient world." 



Mr Longmuir makes the following shrewd remarks, in answering the 

 question, " Whether have we here a mass of Lias clay, as originally depo- 

 sited, or has it resulted from the breaking up of Lias-shale ?' " The for- 

 mer alternative," says Mr Longmuir, "we have heard, has been main- 

 tained ; but we are inclined to adopt the latter, and that for the following 

 reasons : 1. This clay, judging from other localities, is not in situ, but has 

 every appearance of having been precipitated into a basin in the gneiss on 

 which it rests, having apparently under it, although it is impossible to say 

 to what* extent, a bed of comminuted shells. 2. The fossils are all frag- 

 mentary and water-worn. This is especially the case with regard to the 

 Belemnites, the pieces averaging from one to two inches in length, no work- 

 man having ever found a complete specimen, such as occurs in the Lias- 

 shale at Cromarty, in which they may be found nine inches in length. 3. 

 But perhaps the most satisfactory proof, and one that in itself may be 

 deemed sufficient, is the frequent occurrence of pieces of Lias-shale, with 

 their embedded Ammonites ; which clearly show that the Lias had been 

 broken up, tossed about in some violent agitation of the sea, and churned 

 into clay, just as some denudating process of a similar nature swept away 

 the chalk of Aberdeensbire, leaving on many of its hilla and plains the 

 water- worn flints, with the characteristic fossils of the Cretaceous for- 

 mation." 



