8 
Measures was cut through, and then a little of the Pennant, 
followed by “a fault,” caused by the New Red coming in, much 
broken up, and out of which a large quantity of water came 
into the works. The Pennant again appeared, and was esti- 
mated to extend 1600 feet, with a depth of 400 feet, and then 
there succeeded about two feet of lower Coal Measures. A full 
account of the beds passed through when sinking the shaft on 
the Welsh side, which reached a depth of over 200 feet, is 
given in the President’s Address for 1876, in describing a visit 
of the members of the Club on the 17th August, 1875. At 
that time there existed much cause for apprehension that when 
the “Shoots” were reached deep fissures might stop the works. 
The Engineer then expressed himself confident of success, and 
although difficulties occurred in the progress of the under- 
taking which were not anticipated, owing to the very large land 
springs which at one time flooded part of the tunnel, the whole 
of it, which is four miles long, has now been completed, and 
the work is a fait accompli. 
The tunnel mouth on the Bristol side enters the alluvium, 
and the cuttings are full of interest, but required a longer time 
for examination than was at the disposal of the Club. The 
succession of beds from the surface is as follows:—About ten 
feet of yellow clay, one to two feet of peat, six feet of blue clay, 
one foot of peat, five feet of loamy sand, and then a mass of 
gravel 12 to 18 feet thick, resting upon the New Red Marl. 
There is evidence of the existence of at least four ‘ Pills” 
occurring at different levels, the bottom of the largest being 
about six feet below the present low water level in the channel. 
In the fine sand of the gravel marine shells were found, 
including Cardiwm edule, and Tellina solidula. — 
The bottom beds of the gravel were much coarser than the 
upper layers, and a short distance before they thinned out, 
were angular and little water-worn. There were large boulders 
in the gravel, pebbles of Quartz, Millstone Grit, Coal Measures, 
Sandstones, Slate from Cumberland, Lickey Pebbles, fine 
Quartzite, Old Red Conglomerate, Trap Rocks, and some rolled 
Lias Gryphites. | 
