part 1] aAFLT and lower geeexsais^d jstear leighton. 



4a 



have once extended over a wide area in the district, as I found 

 traces of it in 1904 under the main outcrop of the Gault east of 

 Tharae, between Kingsey and Aston Sandford, in the then -un- 

 finished cuttings for the Great Central Eailway. At the north- 

 western end of a cutting in Gault, I saw a poor exposure of" 

 ferruginous sandy loam full of bits of ironstone and lydites. The 

 Gault was a dark-blue rather silty clay, with ' Belemnites minimus ' 

 and small brown-coated phosphatic nodules, seen to a dejDth of 

 8 feet. 



When it became evident that the fossiliferous material obtained! 

 by the Geological Survey in 1885 from Long Crendon was- 

 identical, both lithologically and palseontologically, with the dis- 

 puted Shenley rock, steps were taken by the Geological Survey to^ 

 re-investigate the section, now entirely obliterated by slips and 

 overgrowth. The requisite permission having been obtained, a 

 trench was dug, in the autumn of 1920, in the sliding clay-slope- 

 above the old stone-pit, and was carried across the base of the 

 Gault and its accompanying beds. From my examination of 

 the cutting soon after it was made, I obtained the information 

 shown in the following figure. 



Fig. 18. — Section in flie trench at the east side of Long Crendon 

 Windmill pit ; September 24th, 1920. 



Surface at the top of the slope, about 400 feet O.D. 

 E. W. 



Scale: Vertical and horizontal 



\ Old 

 \ stonc'pit 



1 alu& 



The trench, a foot and a half wide at the top, 2| feet at the lower part, was cut in 

 steps, tbe upper part entirely in sliding Gault, but the lower part touching Gault 

 in place, or onl^^ slightly displaced. AH the beds were more or less affected by 

 surface weathering. 



T7iicJcne$9, 



Z. Brown, passing down into blue, cla3'^ey soil, with scattered"^ 



flints (the largest seen, 4 inches in diameter) , passing >■ about 2 feet, 

 down into — ) 



Z. Rather pale blue-grey mottled clay (Gault), somewhat dis- 

 4 turbed, with some shattered small brown-coated phos- 

 phatic nodules seen about 2 ft. 



