TIDDEMAN : CARBONIFEROUS ROCKS IN UPPER AIRE-DALE. 489 
from this, budding off as it were from it on the North, near Airton, 
and this is succeeded by (5) A small syncline lying just south of the 
village of Malham. 
We have already stated that the white limestones are only 
sporadic in their distribution. We may also state that they occur 
on at least tw^o, and probably more horizons. Referring to the Table 
of Rocks, we may say that they occur both in the Clitheroe Limestone 
and in the Pendleside Limestone. They are far more abundantly 
distributed on the former horizon in the Clitheroe District than in 
this northern part. On the other hand they are commoner in this 
part on the horizon of the Pendleside limestone than on any other. 
The. great anticline of limestone so much worked near the Leeds 
and Liverpool Canal to the north east of Skipton at Haw Park and 
Skibeden is mostly of black limestone. It is probably of the same 
horizon as the Bold Venture Quarries at Chatburn, and certainly 
belongs to the Clitheroe set of Limestones. 
The big patch of limestone extending from Otterburn by Winter- 
burn and Hetton to Rylstone, is on the Clitheroe horizon, and is all 
of the black limestone, except a small patch on its surface at Haw 
Crag Quarry, above Bell Busk, where the limestone has a decided 
reef character, and perhaps also on the hill east of Winterburn, but 
this is more doubtful. This anticlinal area of limestone shows a 
thickness of upwards of 2,000 ft. without a base. 
Limestones of reef character also occur near Pot House and 
Holmes Gill Green, but they are much disturbed, and cannot be 
regarded as typical examples of reef-knolls. 
The Pendleside Limestone is separated from the Clitheroe Lime- 
stone below by a thickness of 2,000 or 2,500 feet of shales with 
impure limestones and mudstones, which may be seen in the Winter- 
burn Valley, in the Aire Valley from Newfield quarry to and beyond 
Kirby Malham, east of Rylstone, and in other places. 
The great interest attaching to them lies in their approaching 
with this thickness so near to the faults in this area, though entirely 
absent to the north of them. The range of the Pendleside Limestone 
may be followed on the maps without much difficulty. It crosses 
the Aire Valley between Kirby Malham and Malham. A good 
