GLACIAL MAEKINGS IN THE KED MARL. 
231 
contorted in a remarkable manner, as if they had been subjected to 
an intense grinding action, and this peculiarity I have noticed to be 
very common in the neighbourhood. 
The section, however, to which I especially wish to call attention 
occurs near Small Heath, at Mr. Sames’s brickworks, situated at the 
junction of Garrison Lane and Cattell Eoad. When I first saw the 
pit I put it down as merely a section of red marl, but a closer inspec¬ 
tion revealed many points of interest, and that the lower part only 
is red marl, with the usual bands of white shale. Above this is a layer 
about three feet in thickness of an unusually hard shale or sand¬ 
stone, called by the brickmakers roche, and surmounting all a bed of 
very tenacious clay which varies in thickness according to the 
surface, but in its deepest part is about thirty feet, including about 
four or five feet of soil and gravel. The dip of the beds is about 
5° S.S.E., and they are faulted shortly afterwards against the 
waterstones, the next lower division of the Trias formation. The 
I 
fault runs right through the town, extending in fact from Barnt 
Green to Sutton Coldfield. The hard band is not found else¬ 
where in the neighbourhood, which is probably owing to the 
slight dip and the fact that this clay pit is situated on the 
highest point in the immediate locality. The height is in fact 430ft. 
above mean sea-level, while the next elevation near is only 420ft., the 
hard band indeed determining the escarpment which runs for some 
distance as a steep hill overlooking the whole town of Birmingham. 
The clay above the hard band contains some of the grey bands, but 
much twisted and broken. It is of a very different quality from the red 
marl, and bricks made from it fetch twice the price of those made 
from the latter. 
Dr. A. Hill has very kindly made for me a chemical analysis of the 
different beds, which I reproduce here :— 
Red Marl. 
Hard Band. 
Boulder Clay 
Silica 
.. 63-07 
37-55 
54-38 
Peroxide of Iron .. 
.. 8-30 
4-82 
15-65 
Alumina 
.. 10-54 
8-16 
16-58 
Calcium Carbonate 
.. 4-53 
25-80 
1-02 
Magnesium Carbonate 
.. 9-05 
13-29 
7-27 
Potash 
.. 1-26 
3-05 
4-47 
Sodsi • • • • • • 
.. 0-48 
0-04 
0-15 
Water 
.. 3-43 
6-99 
0-94 
100-66 
99-70 
100-46 
This analysis shows a 
considerable 
difference in 
the 
percentages 
of silica, and alumina in the Bed Marl and Boulder Clay, when 
we take into consideration the fact that the samples were taken from 
the same section, but it is uncertain whether the discrepancy can be 
attributed to the results of Glacial action. There is a remarkable 
difference in the proportions of the soluble constituents, which might 
possibly be caused by the dissolving out of these substances during the 
rearrangement of the strata. We cannot learn much, however, from 
