526 Geological Notes. By G. A. Lebour, M.A., F.G.S. 



grains of ironstone from some of those same shales, of whinstone 

 (dolerite) from the dyke that crosses the country, and of a num- 

 ber of miscellaneous stones from the drift deposits. 



Calc- Tuff is -pevha-pshetter shown near Elsdonthan anywhere 

 else in Northumberland, Springs throwing up the hard water 

 and depositing the light, porous, limy travertine abound here, 

 and a little to the east of Dykenook, the soft greyish mounds 

 cover quite a large extent of ground. If situated in some fashion- 

 able neighbourhood these springs would long ago have won 

 renown as " petrifying '! wells. 



Alluvium, the result, to a great extent, of Eainwash, sandy, 

 gravelly of every degree of coarseness, loamy, and in a few cases 

 clayey, occurs here in some quantity, forming the great flat 

 haughs by the river Eede, which, near Elsdon, is at its deepest 

 and most sluggish, and the smaller ones by Elsdon Burn and 

 the other minor streams that water the country. It will be 

 noticed that when gravelly, the stones are chiefly of sandstone, 

 limestone, and (sparingly) of basalt, not (except perhaps a few 

 rare pebbles derived from the drift) of the Cheviot Porphyrite 

 which is so common in the gravel alluvia of Ooquetdale. 



Peat also abounds, from that now forming in the wet bogs so 

 numerous on the heights round the village, to ancient peats show- 

 ing where similar bogs once were, and might be once more, should 

 the ancient natural conditions — altered by human agency — ever 

 be allowed to prevail again. 



The Sub-recent Deposits are not specially well shown in the 

 district, but they are represented by the so-called peat marls, or 

 white and yellow clayey deposits, which occur at the base of al- 

 most every peat moss. These can be seen in drainage cuttings 

 in the large bogs about Harwood. 



The term Moor Gravels was applied by the writer a few years 

 back to some problematical pebbly deposits, found in the western 

 part of this county, in irregular patches and mounds on high 

 moorlands, far above the ordinary kaims or eskers to which they 

 otherwise bear some resemblance (1). Gravels of this kind are 

 widely though thinly spread to the East of Elsdon. 



Moraine heaps. A beautiful example is to be seen in the 

 little Lisle Burn Valley, near East Woodburn, some distance, it 



(1) See Lebour's "Outlines of the Geology of Northumberland," (1878), 

 p. 14. 



