368 adamson: sections exposed in skipton and ilkley railway. 
then entered about 400 yards in length. The greatest depth is 
31 feet, and here the Yoredale Rocks are exposed. They consist 
largely of black shales, but contain also beds of earthy and sandy 
limestones and sandstones. In this cutting the beds observed were 
black shales dipping to the S E., at an angle of 25 degrees, and a 
little further on were beds of black limestone, which had been stained 
by decomposed organic matter, for, on breaking pieces off, a peculiar 
fetid smell was felt, somewhat resembling that from petroleum. The 
dip soon caused these strata to disappear, their place being taken by a 
drab-coloured, fine-grained gritstone, containing specks of mica. This 
was evidently a valuable stone, as it had been used for bridges, &c. 
We emerged upon an embankment about 350 yards in length, and 
from this point excellent views were obtained. Another cutting, about 
300 yards long follows, not yet commenced. We now arrived at 
the deep, well-wooded ravine of Lob Gill, cut through the Yoredale 
shales by the action of a small rivulet. Here and there the shales 
were exposed, weathering into their original state of clayey mud. 
The ravine will eventually be crossed by a viaduct of five arches, at 
a height of 70 feet above the bed of the stream. The Cutting 
No. 10a was now traversed about 300 yards in length, with a 
maximum depth of 26 feet. The black shales were extremely 
bituminous. Another short embankment, about 200 yards in length, 
was then crossed to Cutting No. 11, about 250 yards in length, with 
a maximum depth of 17 feet. For about 70 yards at the Skipton 
end of the cutting a yellow clay was noted filling up a depression in 
the strata. Then the gritstones re-appeared, the latter becoming as 
we passed more shattered in their character, and containing con- 
cretions or nodules largely charged with iron. When broken these 
nodules displayed a number of concentric coats. In this cutting, 
also, nearer the Ilkley end, the sandstone was observed interbedded 
with shales, the former in one great example stretching like a tongue 
into the latter. Crossing another embankment, a little over 300 
yards in length, we entered Cutting No. 12, about 530 yards long, 
with a maximum depth of 10 feet. This was cut through a yellow 
stony clay, but no large boulders were seen. An embankment, nearly 
600 yards in length, had now to be traversed to reach Cutting 
