16 FORMATION OF THE SOCIETY: UNPUBLISHED RECORDS. 
whole of the coal measures of a district were deposited during a 
period of comparative repose, during which there were only gradual 
risings and fallings of the land, the general dip of all the beds should 
be pretty nearly uniform, if during the deposition there were oc- 
casional convulsions the successive beds should have occasionally 
different dips. 
These points I mean to notice as worthy of investigation since 
the lecture is to be published, and I should feel obliged to you if you 
could suggest to me any other topics which may have escaped me 
that appear to you from your local knowledge to be such as are 
worthy to occupy the attention of a Society, having for its object 
the investigation of all the natural phenomena and the development 
of the mineral resources of the district. 
The offer of a drive to Wharncliffe tempted me as you saw to 
stay longer than I intended in Yorkshire, I got to Durham about 
five o'clock this morning. 
With kind regards to Mrs. Embleton. 
Believe me, my dear Sir, 
Yours very truly, 
James F. W. Johnston. 
T. W. Embleton to Prof. Johnston. 
MiDDLETON, 22nd Jane, 1838. 
My Dear Sir, 
I was favoured with your letter yesterday, I regret I did not 
meet with you in Leeds on Saturday. I understood you had left 
your hotel, and I had not an opportunity to call again ; I hasten to 
answer your enquiries. 1st, The Cleet " seldom or ever runs parallel 
with the water level, and consequently not at right angles to the dip, 
the general dip being to the S,E. 2nd, It is tolerably uniform in 
direction in the same seam, but is not affected by the regular dip of 
the strata. 3rd, It is somewhat different in each seam, worked in the 
same pit, that is, an upper seam will have the Cleet dissimilar to 
that succeeding it, but the next will have it the same as the first and 
so on, the different layers in each seam present the same phenomena. 
4th, No two water level drifts, commenced from the same points in 
different seams, will coincide with each other, inasmuch as the thick- 
