284 J, F. BLAKE AND W. H. HUPLESTON ON 



grounds in which Mr. Smith, and others before him, have worked, 

 and where first the name " Coral Rag " was applied ; others, which 

 have been admirably illustrated by Mr. Win. Lonsdale, in the 

 1 Transactions ' of this Society, 2nd series, vol. iii. pt. 2 ; others 

 again, on which the officers of the Geological Survey have written* ; 

 and others that have come under the study of the geologists of 

 Oxford, among whom must be particularly mentioned Mr. Whit- 

 eaves, who gave a list of all the fossils found by him in these 

 rocks f, and Prof. Phillips J, who added various particulars and 

 comparisons. By all these we have profited, especially by Mr. Lons- 

 dale's work ; but our studies in the field have thrown much further 

 light even on this area than we had previously been able to obtain. 

 Our separate sections commence with, 



1. The Westbuky District. 



The chief interest of the Corallian beds in this neighbourhood un- 

 doubtedly centres in the iron-ore, which, at the time of our visit, 

 was being energetically worked. The large excavations on either 

 side of the railway-station afford excellent sections for study. The 

 deposit appears to be of very limited extent, occupying a narrow 

 strip of ground running nearly north and south ; although its actual 

 boundaries have not been traced, it is stated to terminate in both 

 these directions at a very short distance from the extreme workings, 

 which are not more than half a mile apart. To the west it crops 

 out; and to the east it dips beneath the Kiinineridge Clay. How far 

 it may extend beneath the surface in that direction is not known. 

 A well sunk about halfway between the town and the railway- 

 station, after passing through about 50 feet of Kimmeridge Clay, 

 showed that the ore had diminished to a thickness of 2 feet. When 

 last seen it is under the influence of a local rise; but its general dip 

 is from 3° to 4° to the east. A fresh-cut surface in a working north 

 of the railway gave the following : — 



Section of the Westbury Ironstone. 



Baring : — ft. in. 



Soil and top clay 3 



Sand and marl in pockets (quaternary ?) 6 



Stiff unstratified clay (redeposited Kimmeridge) 5 



Mixture of ferruginous sandy clay and iron oolite 1 



Ore :— 9 G 



1. Dark earthy friable stone, rather oolitic: contains a band of 



hard blue shelly rock 2 



2. Dark green blocks of earthy and oolitic stone §, in layers from 6 in. 



to 9 in. thick, with much ferric hydrate along the joints and 



lines of bedding 7 



3. Band of oxidized stone 3 



4. Dark oolitic stone to floor of working 4 



13 3 



* Explan. of Sheets 13 & 34. t Ann. Nat. Hist. 1861, ser. 3, vol. viii. p. 142. 



% Geology of Oxford. 



§ In tlie Jermyn street Museum are specimens of these ores with analysis 

 attached, showing 42 per cent, of iron in the brown portions and 37| in the 

 green. 



