210 Observations on Underground Temperature. [April, 



of temperature is under discussion. In my communication to the 

 Koyal Society I have ventured to suggest that the discordant results 

 obtained at Rose Bridge and Dukinfield are to be attributed to the 

 difference in the inclination of the strata at the two collieries, and I 

 propose to enter a little more fully into the discussion of the ques- 

 tion here. I shall now describe in detail the position of the strata 

 in each locality. 



Sections showing relative positions of the strata at Rose Bridge 

 and Dukinrield Collieries. 









Rose Bridge Colliery. 







■*"c — 



CY 



T\ 





- 











- ' ~ — = 7, 







— -*y 





=== ^ 











±*LEY 



MINE J 



Dukinfield Colliery. 



Scale of Feet. 



Rose Bridge Colliery. — That part of the South Lancashire Coal- 

 field known as " the Wigan Coal district," is traversed by a series of 

 parallel faults, ranging in a north-westerly direction, with occasion- 

 ally very large displacements of the strata. These faults divide the 

 coal-field into sections or " belts ; " and where the strata are let down 

 between two faults, a " deep belt " is produced ; on the other hand, 

 where the strata are thrust up, "a shallow belt" is the result. The 



