140 THE BATH OOLITE PERIOD. CHAP- 



Crossing over to the drainage of the Nene, and still proceeding 

 north-eastward, we find the series enlarged and thickened in parts, 

 viz. : 



Cornbrash . . . 8 or 10 feet. 



Forest marble and clays . . . . . . . 5 to 10 feet. 



White oolite . . 20 or 30 feet. 



Blue clay ... . . . . . .15 feet. 



Variable sands, white, grey, and yellow . . . 10 to 20 feet. 



(Occasional and variable limestones) . . . . 20 to 30 feet. 



Ironstone . . . . . . . . . 10 to 30 feet. 



In the country north-east of Northampton we find these strata 

 continued ; and in addition, it is believed by Mr. Sharp, toward 

 the lower part of the series, probably above the variable sandy 

 zone, a thick bed of oolitic limestone comes in, which may 

 perhaps with confidence be referred to the upper or middle portion 

 of the Inferior oolite of Cheltenham. This oolite is continued into 

 Lincolnshire, with great part of the superincumbent beds. 



Regarded in a general manner, then, the Bath oolite series, in 



o 



Cornbrash and Forest Marble. 

 . G R E A T O L I ? E< 



LIAS. 



its course eastward from Cheltenham to Stamford, may be repre- 

 sented in a sectional Diagram, as above ; wherein the fuller's-earth 

 is found in thickness to die out eastward, and the Inferior oolite 

 first to be contracted to almost a line above the lias, and then 

 to be expanded again in two or three parts, the lowest being an 

 ironstone band. 



The subdivisions of this great oolitic mass are not yet fully traced 



