1 80 THE CRUISE OF THE BETSEY ; OR, 



paper of Mr Sedgwick and Sir R Murchison "On the Old Red 

 Sandstone of Caithness and the North of Scotland generally," 

 which forms part of the second volume (second series) of the 

 " Transactions of the Geological Society," and with the de- 

 scription which it furnishes, among many others, of the rocks 

 in the neighbourhood of Thurso. Calcareo-bituminous flags, 

 grits, and shales, of which the paving flagstones of Caithness 

 may be regarded as the general type, occur on the shores, in 

 reefs, crags, and precipices ; here stretching along the coast 

 in the form of flat, uneven bulwarks ; there rising over it in 

 steep walls ; yonder leaning to the surf, stratum against stra- 

 tum, like flights of stairs thrown down from their slant posi- 

 tion to the level ; in some places severed by faults ; in others 

 cast about in every possible direction, as if broken and con- 

 torted by a thousand antagonist movements ; but in their 

 general bearing rising towards the east, until the whole cal- 

 careo-bituminous schists of which this important member of 

 the system is composed disappear under the red sandstones 

 of Dunnet Head. Such, in effect, is the general description of 

 Mr Sedgwick and Sir R Murchison, of the rocks in the neigh- 

 bourhood of Thurso. It indicates further, that in at least 

 three localities in the range there occur in the grits and shales, 

 scales and impressions of fish. And such was the ascertained 

 geology of the deposit when taken up last year by an inge- 

 nious tradesman of Thurso, Mr Robert Dick, whose patient 

 explorations, concentrated mainly on the fossil remains of 

 this deposit, bid fair to add to our knowledge of the ich- 

 thyology of the Old Red Sandstone. Let us accompany Mr 

 Dick in one of his exploratory rambles. The various organ- 

 isms which he disinterred I shall describe from specimens be- 

 fore me, which I owe to his kindness, the localities in which 

 he found them, from a minute and interesting description, for 

 which I am indebted to his pen. 



Leaving behind us the town at the bottom of its deep bay, 



