The Bagshot Beds of Bagshot Heath

Abstract

In the ‘Geological Magazine’ for August 1891 Dr. Irving advocates the adoption of a twofold division of the beds of the Bagshot Series of the London Basin, and in the ‘Proceedings of the Geologists’ Association′ for July 1891 Mr. Hudleston (p. 102) suggests a slight alteration in the system of subdivision at present adopted for that series. I must say I am opposed to these changes, and I may at once point out that Dr. Irving himself uses the terms “Middle Beds,” “Middle Group,” and “Lower and Middle Group” in the paper referred to—very good evidence, I think, of the practical convenience of the threefold division now in use. I think that a good deal of the controversy which has arisen in relation to these beds is due to the unfortunate adoption by Dr. Irving of the well-section at Wellington College as the type, instead of the much more satisfactory section at Goldsworthy Hill originally adopted by Prof. Prestwich in 1847. I call the well-section at Wellington College unsatisfactory for several reasons, one of which is that two accounts apparently of the same well are given in the ‘Memoirs of the Geological Survey,’ vol. iv. (1872) p. 425, which differ in material details. If they do both relate to the same well I should prefer the account given by Prof. Rupert Jones to that of the well-sinkers, even though they preserved a series of specimens. There is one light alteration which I think Dr. Irving, Mr. R. S. Herries, Leiut.