Chap. II.] 
CAMBEIAN EOCKS OF THE LONGMYND. 
25 
ancient sediments of England and "Wales. Bearing the name of ( the Long- 
mynd,' these round-backed hills, which flank the western side of the road 
from Ludlow to Shrewsbury, attain heights varying from 1400 to 1600 
feet above the sea. Eanging from NVNYE.'to S.S.W., they rise boldly out 
from beneath the surrounding Silurian deposits, of which they form the 
mineral axis. 
The annexed woodcut conveys some idea of their form to the spectator 
looking from one of the transverse openings on the eastern slope towards 
the valley of Church Stretton. The elevations perceived beyond these 
hills are, first the Caradoc ridge, then the Wenlock Edge ; the Clee Hills 
appearing faintly in the distance. 
The Longmynd*. 
The lowest strata of the Longmynd, or those forming the base of their 
eastern escarpment, range along the western side of the Stretton valley. 
They are thin, fragile, glossy schists or clay- slate, with two or three 
minute layers of siliceous limestone, each scarcely exceeding an inch in 
thickness. These beds, partially interfered with by bosses of eruptive 
rocks, dip to the and are overlain by a vast and regular series 
of hard, purple or plum-coloured, greenish, and grey schistose flag- 
stones and siliceous grits. The whole of this series can be well observed 
in order of superposition along the banks of the small brook which de- 
scends by the Carding-mill to Church Stretton, and in other parallel 
transverse gullies. Quartz veins occur here and there ; but on the whole 
these strata consist simply of sandstone rock, both schistose and gritty, 
and often finely laminated, in which the lines of deposit, and even the 
rippled surfaces of the beds, are distinctly visible, the mass being but 
slightly affected by slaty cleavage. 
The rocks of the Longmynd proper, highly inclined to the W.N/W., are 
overlain in that direction by other masses of very considerable dimensions, 
including purple sandstones, conglomerates, and grey schists, which range 
* This sketch, and several others relating to for publication by my esteemed friend the late 
this tract, which were made use of in the publica- Mr. Arthur Aikin, but which he had put aside for 
tion of the ' Silurian Sytem,' were drawn by that some years, when, perceiving that I had discovered 
sound geologist, the late Mr. Thomas Webster, in this region an order of succession which had 
many years Secretary of the Geological Society, escaped him and his associate, he kindly placed 
These drawings were prepared to illustrate a ma- his materials at my service, 
nuscript on the geology of Shropshire, intended 
