577 
glacier approached these conditions, the larger the proportion 
of scratched stones we might expect. Now we do find 
evidence of the great extent of the ancient ice streams, and, 
moreover, see, as before noticed, that the oldest drift of which 
we know anything in this district, and which contains the 
largest proportion of scratched stones, lies in the sheltered 
and embayed parts of the hill country. 
ON A SYSTEM OF ANTICLINALS IN SOUTH CRAVEN. BY LOUIS C. 
MIALL, ESQ., CURATOR OF THE BRADFORD PHILOSOPHICAL 
SOCIETY. 
The Carboniferous district of Yorkshire may be conveniently 
divided into three parts: (1.) the Coal Field; (2.) South 
Craven, in which the southern type of lower Carboniferous 
rocks prevail; (3.) the tract north of the Craven Fault, 
which includes the valleys of the Yore, Swale, and Tees, with 
a considerable mountain district in which those streams rise, 
and is characterised by the complex northern series of strata. 
The typical northern and southern series may be found in 
the writings of Sedgwick and Phillips, but I must add two 
or three explanations to prevent misconception. 
1. The two series are not to be taken as uniform over 
considerable areas. A distance of two or three miles is often 
sufficient to produce important variations, and we find the 
southern series gradually passing into the northern one by 
the sub-division and increased thickness of the beds. Perfect 
regularity of deposition is quite consistent with great local 
variations in vertical sections. 
2. In many parts of South Craven, particularly near 
Skipton, the southern series becomes even less divided than 
the table would indicate. The limestone shales are repre- 
sented by a dark, laminated limestone, which passes upwards 
into black or ferruginous shales, and downwards into the 
