h- n. 
REPORTS OF THE PROCEEDINGS 
OF THE 
GEOLOGICAL & POLYTECHNIC 
I 'society 
OF THE 
WEST EIDING OF YOKKSHIRE, 
1851 . 
L'E 
:i 
■Y6I 
i\*n 
Contents* 
Page 
Meeting at Sheffield, June 
5th, 1851— 
“ On the Microscopical Struc- 
ture of the Calcareous Grit of 
the Yorkshire Coast,” by Hy. 
Clifton Sorby, Esq., F. G. S. . 197 
“ On the Use of the Barometer 
in Coal Mines, and a Cheap 
Form of Instrument for that 
Purpose,” by Wm. Sykes 
Ward, Esq., F. C. S., of Leeds 206 
“ On some Phenomena and Ex- 
periments upon Capillary At- 
traction,” by Mr. Thos. J. 
Pearsall, F. C.S.,of Leeds... 209 
Meeting at Bradford, Oct. 
17th, 1851— 
Statement of Accounts 213 
Page 
“ Description of a Direct- Acting 
Steam Fan for the Better 
Ventilation of Coal Mines,” 
by James Nasmyth, Esq., of 
Patricroft, Manchester 214 
“ Description of the Fan erected 
for the Ventilation of the 
Hemingfield Pit, belonging to 
Earl Fitzwilliam, at Elsecar,” 
by B. Biram, Esq 215 
“ Description of an Improved 
Safety Valve for Steam 
Boilers,” by J. Nasmyth, Esq. 218 
“ On the Contorted Stratifica- 
tion of the Drift of the Coast 
of Yorkshire,” by Hy. C. 
Sorby, Esq., F.G.S 220 
I. E E D S : 
PRINTED BY EDWARD BAINES AND SONS. 
1852. 
