IRONSTONE FORMATION OF THE FOREST OF DEAN. 269 



I may cite, as a capital instance of the kind of fault produced by 

 erosion, the Horse," which occurs in the Goleford High Delf Yein, 

 and which has been followed over two miles in length, presenting an 

 average breadth of 260 yards. "Mr. Buddie has described the circum- 

 stances connected with this fault, and has represented certain minor 

 phenomena, of apparently the same description, known as the Lows," 

 as tributaries to the ancient main channel (" Geological Transactions," 

 Vol. YI). I am inclined, however, to refer the greater number of the 

 ** Lows," or so-called subsidiary channels, to the same origin as the fault 

 at Ruardean, which I have just described, and I am supported in this 

 view by the fact, that the quartz pebbles and rolled pieces of coal, 

 which are found in the sand and drift (now converted into sandstone), 

 that occupied the main channel, do not occur in the " Lows," — which, 

 moreover, are not all of them connected, as represented in Mr. Buddie's 

 plan, with the Horse." 



In the sandstone of the coal-measures many instances occur of 

 irregular and oblique lamination, affording a proof that the beds were 

 not formed by the gradual deposition of particles mechanically 

 suspended in the water, but rather by drifts of sand pushed along the 

 bottom by the action of currents. The following section was sketched 

 near Cinderford Bridge : — 



(1 



b 



Lign. 4.— Drift-bedding in Sandstone, near Cinderford Bridge.— a, b, c, d, e, Beddings inclined at 



various angles. 



Ikon Ore roRMATioN, 

 I have mentioned, incidentally, that between the double veins of the 

 Woorgreen and Starkey coals, and beneath the Upper Trenchard Yein, 

 there occur in beds of shale bands of ironstone of sufficient thickness and 

 value, in places, to be worked. These ironstones are all of a similar 



