TATE — ON THE GEOLOGY OF BEADNELL. 



69 



Beadnell. Some seem to be the burrows or casts of annelids, passing 

 either perpendicularly or obliquely through several layers of rock, the 

 upper surfac'e of the layers being pitted and the under projecting. 

 These casts or burrows are about two lines in diameter, and are so 

 crowded together in some rocks both at Beadnell and Kirkwhelpington, 

 as to give the stone a pock-marked appearance. Meandering furrows 

 about one line in width, with a ridge in the centre, are probably the 

 trails of an annelid : they occur also at Howick, North Sunderland, 

 and Haltwhistle. It has been suggested that these were tracks made 

 by small crustaceans, but the absence of all remains of the hard shell 

 renders this opinion doubtful, and more extended observations on 

 these borings and trails, and on the other markings associated with 

 them, are required before the true characters can be distinctly 

 determined. 



As confirmatory of the marine conditions of the rocks in which the 

 ripple-marks and annelids are found, I may add, that the flaggy 

 sandstone containing annelids at Howick has in some of the layers 

 Belleroijhon^ Euomphalus, Murchisonia, and Pleurotoinaria, shells un- 

 doubtedly of marine origin. 



The group of facts now noticed gives us a partial glimpse into a far 

 distant era. The Beadnell flaggy beds expose to our view an ancient 

 coast-line : we hear the waves breaking on the shore ; we perceive 

 currents rolling along masses of sand j the tide recedes, and ripple- 

 marks, long ridges and furrows, sharp and distinct, appear ; there, 

 too, are seen worms, some of large size, crawling over the surface or 

 burrowing in the sand. Marks left by the sea are often fugitive, — 

 the impressions made by one tide are obliterated by another ; but 

 here they are preserved ; the sand and mud are hardened, it may be, 

 by a warm sun breaking forth and baking the surface before the 

 return of the tide ; other deposits have covered over the markings, 

 and buried up and preserved the organic forms; and now, when 

 these rocks are laid bare and examined, they reveal to us that the 

 same physical laws operated during the Carboniferous Era as at the 

 present time, and that, though the aspects of vegetation were wonder- 

 fully different, and organic life specifically distinct, yet the animals of 

 the period were formed according to the same types, and were subject 

 to like conditions as those now existing. 



