79 
RECORDS AND COMPARISON OF THREE DEEP BORINGS IN THE 
MILLSTONE GRITS AT HALIFAX. 
BY WM. SIMPSON, F.G.S. 
Three deep borings have been sunk in the dip slope of the 
Grit Rocks of Halifax in search of an increased supply of water 
during the past few years, and in return for such geological 
information as I have been able to give. I was allowed to 
watch the operations and make notes of the strata passed 
through. 
Halifax is built on the Rough Rock, the top member of tlie 
Millstone Grit series. 
At the lowest part of the town, a little to the east of the 
railway line, the Grit series pass under the Lower Coal Measures 
which form the bold escarpment and conspicuous physical feature 
to the east of the town. From here the Rough Rock, which has a 
general datum level of about 400 feet where it disappears under 
the Coal Measures, rises at an angle of about 2' to the west and 
north-west to over the 1,000 feet datum. 
Further to the west and north-west of Halifax. Luddenden 
valley cuts through the various members of the Grit series, 
almost down to the Kinderscout rocks at the base. 
On the easterly terraced sides of this valley, and on the moor- 
lands to the north, the middle series of the Grit rocks are ex- 
posed, and doubtless gather a considerable amount of surface 
water, which following the dip. and directed and held by the 
impervious shales above and below, passes under Halifax at 
varying depths below the surface rocks. 
The Rough Rock, as its name would suggest, is generally 
coarse in grain, very felspathic, and much jointed, and carries 
a good supply of water held up by the underlying shales. This 
