28 FORMATION OF THE SOCIETY : UNPUBLISHED RECORDS. 
substitute for the common pumping engine ; after which a conversa- 
tion ensued between Mr. Holt and Mr. Hartop, relative to the appli- 
cation and economy of this machine ; which ended in a request from 
the meeting that Mr. Holt would institute a further examination into 
the merits of the invention, more especially with reference to its 
effective power, first cost, wear and tear, and its general adaptation to 
coal mines. Mr. Holt promised to comply with the request, and lay 
the result of his inquiries before a future meeting. 
Mr. Briggs, of Overton, produced a model of an improvement 
which he had made in the pulley frame placed at the top of a pit for 
drawing coals, the principle of which he described. He also exhibited 
some round and flat rope, constructed of wire, which he had himself 
made, after reading a description of those used in the Hungarian 
mines. He stated that a wire rope of one inch circumference is 
equal in strength to a hemp rope of four inches ; that the wire rope 
is lighter than, and as pliable as the hemp, and will perform nearly 
double the work. 
The Rev. ^Y. Thorp, of Womersley, read a paper on the 
Yorkshire and Lancashire coal fields. Mr. Thorp's lines of argument 
tended to prove that there were many data in favour of the identity 
of the two coal fields ; in fact, that at one time they were a continuous 
tract. It is impossible to give more than a meagre outline of the 
large mass of information that he had collected on the subject, es- 
pecially as much of that information requires to be elucidated by the 
numerous sections he exhibited. He first described and traced on 
his map the various axes of elevation in the two coal fields, and 
showed the effects produced by those elevations. Again, he followed 
the line of Millstone Grit which underlies both the Yorkshire and 
Lancashire coal fields, and next, the range of two seams of millstone 
grit coal, better known in this neighbourhood by the name of the 
Halifax beds — beds similar to those he pointed out as occuring 
in Lancashire, under the same peculiar circumstances in which they 
are found in Yorkshire. He noticed also the singular fact of the 
deposit of marine shells (Pecten papyraceus) in this part of the 
millstone grit formation. He also pointed out the appearance of the 
flagstone in each field, as another proof of their identity in structure. 
