174 WORGRET HILL AND WAREHAM WATER SUPPLY. 



developed on Highwood Heath and the Luckford Valley. To 

 this succeeds (2) a very strong and well-marked clay series, 

 which varies to a certain extent and produces the phenomena 

 known as "clay knaps" in Dorset. At West Holme this clay 

 series is well developed, and there is every reason to suppose 

 that its upper surface was eroded before the overlying sandy 

 series was deposited. 



The following may be taken as the general section of this clay 

 series as proved on the north side of the hill at West Holme : 



Ft. In. 



Bed of greyish white pipeclay (sometimes 



missing) . . . . 3 o 



Strong variegated clays with blood-red specks 



and blotches on a whitish ground . . 6 o 



White clay . . . . 2 o 



Passing downwards into stiff yellow clay 3 o 



Yellowish waxy clay with a ferruginous line 



towards the top . . . . 3 o 



Horizon of the main ironstone, often of a 

 blood-red colour and associated with 

 variegated clay . . . . . . 2 o 



Clay rather iron-stained towards the upper 



part . . . . . . ..40 



Grey clayey sand without concretions 3 o 



Band of flaggy ochreous ironstone o 4 



Total .26 4. 



The above sequence of beds rests conformably on sands which 

 are believed to belong to No. i, and the clays are capped 

 unconformably by another sandy series (No. 3), which consti- 

 tutes the summit of West Holme Mount, under protection of an 

 irregular spread of gravel. This third series dips away towards 

 the north-east, but is lost to sight in the valley flats of the 

 Frome. 



