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but mingled with these are many rounded fragments of 
granite and other crystalline rocks, whose original site is 
far distant. Some years since, the foundations of a mill were 
laid upon this gravel bed, but on its proving insecure, the 
gravel was found to be only a few feet in thickness and to be 
succeeded by a stratum of a soft peaty nature, so deep that 
a twenty feet pile did not reach the bottom. 
This district of the West Riding is composed of very 
high ground, branching from the great summit ridge of 
England, and intersected by numerous deep valleys, whose 
general direction is nearly east and west. That the 
boulders could have been drifted over this mountainous 
country without leaving some traces of their course, 
is, I think, clearly impossible; and I may here remark, 
that on the adjacent hills not a pehhle of any kind can 
he found. We must therefore look around for some other 
way of ingress ; and before entering upon this branch of the 
inquiry I will briefly allude to those accumulations of drifted, 
or, as it is sometimes termed, diluvial matter, which over- 
spread many parts of England, as well as of the Continent 
of Europe, and which have long engaged the attention of 
geologists. This drift exists in great abundance in the central 
and eastern parts of Yorkshire, the regular strata along 
the whole coast line being generally surmounted by it to 
a considerable depth. It is also plentiful in Lancashire. 
The composition of the detritus is remarkable. The bulk 
is usually clay, with rounded masses of rock of the greatest 
variety of formation and diversity of size, interspersed 
throughout without the slightest degree of stratification, im- 
mense blocks being confusedly mingled with small pebbles.* 
The action of water has usually been considered as the 
moving power ; but as any current would naturally give 
* For a minute description of this formation, see the 1st vol. of Professor 
Phillips's Illustrations of Yorkshire. 
