42 Dr Black on some appearances connected with the 



on elevated grounds ; but in other instances I have observed 

 them to lie immediately under a thin soil and the green sward 

 — evidently shewing, in the majority of cases, that the causes 

 which gave rise to their disintegration and arrangement ex- 

 isted before the period of the great diluvial deposits, which, 

 on their part, give much and strong evidence of a great por- 

 tion of their materials, both rocky and sedimentous, having 

 been transported from distances more or less remote. When 

 the beds under our notice have reposed on the surfaces of tlie 

 mother rocks, which were much inclined, I have observed the 

 laminated fragments to assume a greater horizontality than 

 the subjacent surface of the compact rock ; which affords some 

 evidence that the individual fragments had at one time some 

 liberty of motion, which allowed them to yield a little to the 

 laws of gravity ; though I must say this characteristic has never 

 been observed to be very distinct. (Fide the Sections, Plate II. 

 Figs 1 and 2.) 



- Such being some of the more common features of these 

 fragmentary beds, the next object is to investigate the cause 

 and mode of their formation. I must say, that I at first in- 

 curiously took these beds to be the rough fragmentary de- 

 tritus of neighbouring rocks accumulated in their respective 

 situations by the strong currents of some primeval liood ; but 

 on further consideration, the general parallelism of the frag- 

 ments as they lay in the beds rather militated against this sup- 

 position ; for, if they had been drifted from any moderate dis- 

 tance, they would have been deposited in all directions, verti- 

 cally, inclined, and horizontally. To confute still further the 

 idea, that they were transported by aqueous violence from any 

 distance, the fragments, on a more close examination, were 

 found, however separated and turned round on their vertical 

 axes, to be of the same nature and character with the rocks 

 immediately subjacent. The uppermost layers might shew, in 

 some beds, considerable displacement and disturbance, but the 

 mineralogical similarity, if not identity, of texture could at all 

 times be satisfactorily traced to the parent or solid rock beneath. 

 It was also easy to perceive that these disintegrated beds 

 were in no probable manner occasioned by the general and 

 deep convulsions which had fractured and disturbed tlio sub- 



