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DUNDRY HILL. 



The Oolites of Dundry Hill, near Bristol, have always presented 

 a problem of some difficulty to Cotteswold Geologists, who have 

 found it no easy matter to apply their own local subdivisions to the 

 30 or 40 feet of rags and freestones there developed, so as to bring 

 the two sets of deposits into harmonious relations with one another. 



Mr. Lycett, though evidently entertaining some doubts respect- 

 ing the true correlation of these beds, offers a solution of the question 

 as follows : He says, " at Dundry the quarries are capped with 

 rag-stones, which seem to belong to the Spinosa Stage ;, this is under- 

 laid by useful building freestones, and by sandy Oolite, in all nearly 

 50 feet thick, which, probably, represent the Fimbria Stage. The 

 Cynocephala Stage is here represented by only half-a-yard of ' Sands ' 

 overlying the Tipper Lias Clay." "We have here the Cotteswold 

 series apparently identified at Dundry, and I visited the quarries 

 with the expectation of being able to recognise the equivalents of 

 the three stages as laid down by Mr. Lycett ; but I am bound to 

 record as the result of my observations, my persuasion that the 

 Dundry beds are a repetition and extension of those at Lympley 

 Stoke and Charlcombe, having the Trigonia and Spinosa beds at the 

 base, and resting on the " Sands "as in the last-named localities, 

 but with a greater extension upwards of the freestones, which like- 

 wise assume at Dundry a purer grain, and more even and regular 

 characters. 



The Freestones at Dundry occupy the eastern extremity of the 

 hill, from which point, followed along their line of strike, they 

 rapidly attenuate, so that within an area of less than a mile from 

 their point of greatest extension, they cease to be any longer trace- 

 able. The principal quarries are near the Church, and in what is 

 known as the "Upper Quarry " the following beds are exposed : 



1. Eubbly beds 4 feet. 



2. Hard gritty rock 9 



3. Freestone beds 6 



In these beds fossils are by no means abundant, or of good 

 differential type ; but lying amongst the debris which surround the 

 margin of the quarry, I found a block of stone precisely identical in 

 characters with the "basement-bed" at Lympley Stoke, and like 

 that charged with Trigonia Costata and Rhynchonella Spinosa. Whence 

 derived was the question, and an inspection of that and the adjoining 

 excavations affording no satisfactory explanation, I awaited the re- 

 turn of the quarrymen from their dinner to obtain information on 

 the subject ; and learnt, in reply to my enquiries, that the rock in 

 question lies at the bottom of all, and reposes upon a stratum of clay, 

 which in its turn rests upon Sand. The clay was described as a 

 water-bearing stratum, and in sinking a well for water in the 

 quarry, the workmen had brought up the blocks of " Trigonia and 

 Spinosa grit " from the position indicated. The clay band would 

 appear to be a merely local and accidental deposit ; and I heard a 



