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six and a half inches in circumference. In a brick-field at 
the Reformatory School, Hunger Hill, many of the bricks, 
which were newly made, exhibited the impressions in the soft 
clay caused by the hailstones ; one of these bricks was burnt 
and sent to the Museum of the Philosophical and Literary 
Society of Leeds, in which is one hole two inches in diameter, 
by two and a half inches in depth. — Henry Denny. 
ON THE BASALTIC FORMATION OF THE SOUTH STAFFORD- 
SHIRE COAL FIELD. BY CHARLES TWAMLEY, ESQ., 
F.G.S., OF LONDON. 
The South Staffordshire coal field consists of a long 
wedge-shaped mass of the carboniferous formation, lying 
immediately upon the Wenlock limestone and shale of the 
Silurian system, which has been thrust up through the 
permian and new red sandstone deposits. From its base, 
near Hales Owen, where it is about six miles wide, 
and which there gradually rises from underneath the 
permian and new red sandstone, it extends in a direction 
N.N.E. towards the town of Rugeley, a distance of 
about twenty-three miles, bounded on its two sides 
by two large faults, which converge towards each 
other until they meet near that town. These faults bring 
this wedge-shaped mass of Wenlock limestone and shales, 
and coal measures, into immediate and abrupt contact with 
the permian and new red sandstone, on its east and west 
sides ; but this is somewhat interrupted on the eastern 
side, near Walsall, by the elevation to the surface of the 
Wenlock shale and limestone. The effect of the elevatory 
force which raised this great mass, was to bring the Wenlock 
shale and limestone, and the coal measures, which were 
previously covered with the permian and new red sandstone, 
F F f 2 
