72 



Prof. J. Prestwich. 



Locality, 



111. Norley Coal Co., Wigan 



112. Aberdare, Upper Duffryn* 



Colliery, No. 1 Station. 



55 55 2 „ 

 q 



55 55 " 55 



55 55 ^ » 



113. „ New Tredegar Colliery,! 



No. 1 Station. 



o 



55 55 35 



55 55 3 „ 



4. 



55 55 ^ 55 



114. ,, Dowlais Colliery, Iron- 



stone Mine. 



115. „ Cwmbach 



116. Hetton Colliery, DurhamJ 



lit. South Hetton Colliery, 

 Durham. 



118. Rosebridge Colliery, Wigan 



II 



Place of observation. 



Coal pit 



III 



Height of 

 surface 

 above 

 sea-level. 



IV 



Mean 

 annual 

 tempera- 

 ture of 

 surface. 



Feet. 



ITahr. 



157 



48° 





55 



55 



5) 

 55 



400 



48 -5 



1220 





1330 



•■• 



1540 





720 



48? 



679 





1495 





1287 





1170 



47 



55 



480 



„ 



48'5 



1300 



55 



400 







55 



55 



» 

 55 



55 



204 



55 

 55 





55 



157 



55 

 55 



48 



55 

 55 



# Beyond No. 2 station the circulation of air was partially stopped, and beyond 

 No. 3 station entirely stopped, that part of the colliery having been abandoned for 

 18 months. The other Aberdare experiments were in collieries that were working 

 at the time, and the air not shut off. The temperatures taken 4 feet deep in the 

 coal. 



f Although the surface at No. 3 station is 124 feet lower than at No. 4, it is 



