Correspondence — Professor Prestwich. 



239 



(should be 155) of rock. These beds have also been assigned to the 

 Oxford clay, but Mr. Stackpole speaks of the rock below a depth of 

 265 ft. as referable to the Great Oolite ; but upon what evidence he 

 does not say. If, however, a nearly horizontal line (the dip of the 

 strata is nearly horizontal) be prolonged, from the level at which we 

 have placed the Oxford clay at Wytham, it will be found to coincide 

 almost exactly with the base of the clay at St. Clement's, and both 

 series would naturally fall into the same category." 



I conclude, therefore, that instead of being 600 ft. thick and more, 

 the Oxford clay in the neighbourhood of Oxford does not exceed 320 

 to 350 ft., and further, there is evidence to believe that the Lower 

 Lias itself thins out at no great distance, and even that the New 

 Eed Sandstone is at no great depth beneath Oxford. Besides its 

 geological bearing, this is important in case, at some future period, of 

 any attempt to search for coal in Oxfordshire or Buckinghamshire. 



E. — Section of Wytham Boring. 

 (From Phillips's " Geology of Oxford," p. 296.) 



" The following is a summary of the results obtained in this 

 remarkable boring, copied from a section presented to the Oxford 

 Museum in 1849, by the Earl of Abingdon. The terms employed by 

 the workmen are used in the coal-fields of Stafi'ordshire for strata 

 somewhat analogous : — 



1. Loamy ground ... 



2. Quicksand and water 



3. Blue cluncli 



4. Light clunch 



5. Blue clunch 



6. Clunch bines 



7. Blue clmich 



8. Clunch bines 



9. Blue clunch 



10. Brown clunch 



1 1 . Mingled ground . . . 



12. Strong grey rock 



13. Grey clunch 



14. Brown clunch ... 



15. Mingled ground .. . 



16. Blue clunch bines 



17. Mingled ground ... 



18. Blue clunch 



1 9. Mingled ground . . . 



20. Blue clunch 



21. Dark blue rock ... 



22. Dark parting clunch 



23. Dark blue rock ... 



24. Dark clunch 



25. Strong blue rock 



26. Dark parting clunch 



27. Strong blue rock 



ft. 



12 

 3 



68 

 1 



28 

 4 



29 

 2 



28 

 3 



11 

 1 

 2 

 1 



17 

 6 

 4 



17 

 9 

 5 

 3 

 

 2 



11 



10 

 1 

 5 

 





ft. 



in. 



29. Blue rock 



1 



6 



30. Clunch and clunch bines ... 



6 







31. Grey rock 



18 







32. Dark parting clunch 







6 



33. Light rock 



30 



a 



34. Light parting clunch bines 







9 



35. Light rock 



5 







36 , Very dark parting 



2 







37. Grey rock 



1 



4 



38. Dark parting 







8 



39. Clunch bines 



7 



6 



40. Grey rock 



3 







41. Dark parting 



1 



6 



42. Grey rock 



2 



6 



43. Blue Bines 



2 







44. Mingled ground 



3 







45. Blue rock 



9 







46. Dark ground 



1 



6 



47. Mingled ground 



7 



6 



48. Light rock 



16 



6 



49. Black bat 



2 







50. Eock 



35 



6 



5 1 . Mingled ground 



11 



6 



52 to 55. Mingled ground 



3 







56. L'onstone 







4 



g^,* [Clunch mixed with ironstone 132 







59. Dark clunch 



2 







28. Strong parting clunch 



'•'The boring was carried to the depth of 211 yards, the strata the 

 same as that at 596 feet." — C. Webb. 



" The borins: was made in 1829.' 



Joseph Prestwich. 



