CHAPTER XL 



THE BATH OOLITE PERIOD. 



THROUGHOUT England the upper limit of this large group of 

 rocks is very well marked by the highest bed, ' Cornbrash,' under 

 the Oxford clay, which is continuous across the country north of 

 Oxford. The lower limit is not so firmly settled, because the 

 * Inferior oolite,' which marks the boundary, is far from being 

 so continuous or so uniform in composition or contents as the 

 cornbrash. 



The strata composing the group were all fully studied and 

 named by Smith in the latter part of the last century, near Bath. 

 His series stands thus a : 



Cornbrash. 



Sand and sandstone (of Hinton). 



Forest marble (of Farleigh Castle). 



Clay over the Upper oolite (Bradford). 



Great or Upper oolite. 



Fuller 's-earth and rock. 



Inferior oolite. 



(Sand. Also classed with lias.) 



And it remains without alteration. 



In a general point of view, the whole is a succession of limestones, 

 oolitic or shelly, laminated or massive, alternating with clays and 

 sands locally hardened to sandstones. 



In the following Tabular View the proportions of the several 

 component beds appear as they may be seen about Cirencester and 

 Cheltenham. Some of the more characteristic fossils are mentioned 

 opposite the parts of the section where they are found to prevail. 



a 'Geological Table of British Organized Fossils,' in 'Stratigraphical System.' 

 4to. London. 1817. 



