Xll 
INTRODUCTION. 
In 1825, I examined at leisure the limestone district of Castleton, 
and collected abundance of fossils. Parts of Wharfedale and Swaledale 
were afterwards reviewed ; W ensleydale next drew attention, some of 
its branches were investigated with considerable minuteness, and many 
of the mountains ascended ; drawings were made of waterfalls and 
contours of hills, and sections of strata measured. 
In 1826, I became permanently attached to the Yorkshire Philo- 
sophical Society, and made a long pedestrian tour in Scotland. Arran 
was then viewed with a close scrutiny, and a catalogue drawn up 
of the organic remains of the peculiar carboniferous system there. I 
returned by Troon, Ayr, Cumnock, Sanquahar, and Dumfries, to 
Carlisle ; crossed, for the fourth time, (by the new road then un- 
finished) the great limestone escarpment of Hartside to Aldstone moor ; 
and descended Teesdale. 
In 1827, I again visited Castleton, examined Dr. Henry’s collection 
at Manchester, accompanied him to Primrose near Clithero, and with 
Mr. T. Thompson ascended Pendle hill, and partially explored the 
limestone tract of Bolland. 
In the autumn of this year, a walk through the lake district with 
my friend Mr. T. George completed my survey of the Cumbrian slates, 
and a leisurely review of the Craven fault and its attendant phenomena 
enabled me to draw up for the Geological Society a memoir on that 
district which is printed in the Transactions, (New Series, Vol. III). 
The year 1828 and part of 1829, were devoted to the preparation 
of the first Volume of ‘ Illustrations of Geology of Yorkshire.’ 
In the summer of 1829, I saw and contrasted the mountain lime- 
stone district of the Meuse and the transition limestone of the Eyfel, 
and examined the public collections at Ghent, Namur, and Bonn, 
besides the valuable cabinet of M. Heinkzelius at Maestricht ; all 
of which were useful to my object. In the autumn of the same 
