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others occurred much higher upon the flanks of the hills. This 
dolomitic conglomerate might be of any age from the base of the 
new red to the top, and the patch on which he was standing, he 
(Mr. Winwood) was inclined to think might be of Rhetic age, 
corresponding with that on the Butcombe side of the valley. He 
was strengthened in this opinion by the fact that his friend, Mr. 
Valpy, had found Rhetic fish teeth in a conglomerate close 
adjoining. If the members would ply their hammers and seek 
diligently they might settle the question. 
The engineer, Mr. Ollis, who had previously joined the party, 
now conducted them over the new works, which are of vast 
-extent. The river Yeo rises some distance up the valley, near 
Compton Martin, and the idea has been to intercept its progress 
by throwing a dam across the valley, in the form of a barrier or 
retaining wall, running northwards towards Butcombe, thus 
forming an artificial lake, the area of which will be about 350 
acres and the capacity 2,000 million gallons, with a depth in 
centre of about 36 feet. Of course to retain so large an area of 
water safely, and to prevent percolation, it was necessary that 
special attention should be paid to the foundation of the retaining 
wall; this has been done, and the depth on the Blagdon side is 
90 feet, and at Butcombe 180. When the works are finished, it 
is proposed to pump the water to Barrow, on the other side of 
the hill, where it will be duly filtered and conveyed to Bristol. 
The situation of the works at Blagdon is about 110 feet above 
sea-level. Mr. Ollis pointed out some specimens of the strata 
through which they had cut, and showed the difference in the 
conglomerate beds, one being of a very hard nature and six feet 
thick, the other of a honeycomb character and about three feet 
thick. The members having thanked Mr. Ollis for his kindness 
in giving them so much information, returned to the carriages 
which were waiting a short distance off. A start was now made 
in a homeward direction taking the south side of the Yeo valley 
through Langford. A short stop was made at Congresbury to see 
