aperature in different Mines in Cornwall and Devonshire, and 
ere, with a few exceptions (distinguished by an asterisk), made in 
2 2 4 s 2 
= P= = . 2 
|} 23 3 eS -3 aay Eis) Pee 2 | Ratio of Depth 
ils = : u 
| Depth in ES pe Depth in EH |/2es #2) sus to a given 
| Fathoms 2346 Fathoms. a4 2 sas 99) faqs Increase of 
ie . Bs ass a we £2 & § | Temperature 
a o = 10° 
a & og & alia 2 ae 10°, 
EE ff", 
| 45 
| _—<$$$_—$_<—_ | __. 
- {Surface = 50° 
ao fe 
o uw 
or 
f—] 
ie) 
bo 
oO 
ir) 
66°35 se a 
50°00]) .-. «.. D ‘ 10-13 jor72°81 = 10° 
16°35 104-00) 131-86 = 70° 
16:26 100-00 
50:00 
66°26) 100-00 
