68 
Company’s well in Lewis Lane, after emptying the well by 
continued pumping, and found it 50° Fahrenheit. This water 
was taken at 331.00 ft. on Ordnance datum, and quickly rose 
in the well to 351.20 on Ordnance datum, at which it stood. 
Then took the temperature of the water in an old Roman well, 
at Messrs Crippr’s Brewery adjoining, (in Cricklade Street) 
17 ft. to 20 ft. deep, at 343.00 on Ordnance datum, and found 
it to be 46° Faht. Difference 4° Faht. 
Second experiment at Chalford, 27th March, 1886, 4.50 p.m.: 
air temperature 55° Faht. Spring issuing out of pipe into 
stone trough, near Chalford silk mills, 243.00 ft. on Ordnance 
datum, 512° Faht.: springs on opposite side of valley, issuing 
from under Penny Hill wood, taken inside face of tunnel 
adjoining Great Western Railway, 53° Faht.: spring issuing 
from small pipe near Hyde farm, thrown out by the Fuller’s 
Earth, about 520.00 ft. on Ordnance datum,-—46° Faht. Air 
temperature at 6 p.m. here was 52° Faht. 
Difference of temperature of the springs thrown out by 
the Upper Lias and by the Fuller’s Earth 53° to 7° Faht. 
Difference of level 277 ft. 
Mr J. G. Symons, Iam informed, has made an admirable 
series of observations on the increase of temperature at various 
depths, and it has been ascertained that for every 50 or 55 feet 
in depth the water increases in temperature 1° Fahrenheit. 
At the Rosebridge Colliery, at Ince, near Wigan, the deepest 
mine in this country, having reached a depth of 2,445 feet, 
experiments on temperature, whilst sinking the pit, showed an 
average increase of about 1° Faht. for every 54 ft., whilst the 
Royal Coal Commission, in their calculations, adopted 60 ft. 
for every degree Faht. This would not alone explain the dif- 
ferences of temperature, as my observations were made at 
Chalford at the spring outfalls, and not underground, but, if 
taken in conjunction with the increase of heat due to hydro- 
static pressure, they will help to do so. 
We have now traversed some 300 sq. miles of our Cotteswold 
district, with about 100 sq. miles of the hill-side around Old 
Swindon, and have noted some of the circumstances and facts 
