260 
PROCEEDINGS 1849 — 1858. 
research to slate rocks. Rounded and concretionary grains included 
in the slate matrix were found to be greatly elongated and distorted, 
or broken up in such a manner as to indicate that there was a con- 
siderable change of dimension ; the results are summed up in the 
following sentence : — " I may state my firm conviction that there is 
abundance of facts to prove that the slate rocks have undergone a 
very considerable change of dimensions, to which the cleavage is 
distinctly related, having been greatly compressed in a line perpen- 
dicular to its plane, and elongated in that of its dip." Such a change 
would necessarily alter the arrangement of their ultimate particles 
from that which is found in rocks not having cleavage, and hence 
develope a line of structural weakness in the direction in which it 
occurs. 
The Society at this period does not appear to have been in a 
very flourishing condition. The honorary secretary resided at a con- 
siderable distance from the area of its operations, which naturally 
rendered it difficult for him to give that careful and ready attention 
to the details of management which are essential to secure success. 
Mr. Thorp decided to resign his post, and intimated his intention to 
Mr. Thomas Wilson. The latter communicated with some of the 
principal members, and sought their help in placing the Society in a 
position of greater financial security. The letter following was sent 
to Mr. T. W. Embleton. 
3!r. Wilsoji to Mr. Embleton. 
Crimbles House, Leeds, 
My Dear Sir, ^6th August, 185 Jf. 
Mr. Thorp wrote to me a few days ago, saying that he had written 
to Mr. Denny, to resign the office of secretary to the Geological 
Society. He had previously, some two months since, expressed to 
me an opinion that the Society could not be carried on. 1 had there- 
fore previously to, and independently of his resignation, turned my 
thoughts to the present position of the Society and to the considera- 
tion of the question, whether it must be given up or could still be 
carried on. I own to the greatest disinclination to abandon it without 
every eff ort being made to continue it, because I conceive it has 
already been of great service to the cause of local Geology, and may 
