WORGRET HILL AND WAREHAM WATER SUPPLY. 167 



round Dorchester" (1899). In the former memoir the author 

 (page 3) speaks of several hundred feet of sands, interbedded 

 with numerous lenticular masses of carbonaceous loam or clay 

 containing fossil leaves, as resting on the London Clay. These 

 are the Bagshot Beds, the strata being mainly of fluviatile origin. 

 It is evident from the position assigned to the principal pipeclay 

 beds round Poole Harbour, viz., about 200 feet above the London 

 Clay, that they hardly occupy the same position in the Bagshot 

 system as the great series of claypits between Creech Grange 

 and Corfe Castle. 



In the " Geology of the country round Dorchester " the same 

 author remarks (p. 25), that "At the eastern margin of the area 

 described in this memoir, the Bagshot Sands are of the same 

 type as those round Poole and Bournemouth." That is to say 

 that the Bagshot Beds are mainly constituted of sands mixed 

 with lenticular clay bodies. As regards the total thickness of 

 the Bagshot system in the Wareham district we have no direct 

 information from Mr. Reid, but the following passage (p. 25) 

 may possibly throw some light on the as yet unproved strata 

 below the termination of the Worgret borehole. " Close to 

 Organ Ford, and for nearly a mile to the westward, white pipe- 

 clay mixed with carbonaceous clay can be seen in the road south 

 of the stream. This bed is apparently equivalent to the stratum 

 that is worked at its southern outcrop round Creech, though at 

 its northern outcrop it does not appear to be more than 50 feet 

 above the London clay." The statement is important as showing 

 that in the neighbourhood of Organ Ford, rather more than 

 three miles due north of Wareham, the Pipeclay series, towards 

 its northern outcrop, is quite low down in the Bagshot system. 

 Now, when we come to consider the bearing of these facts on 

 the hypothetical estimate of 85 feet for the " Remainder of the 

 Bagshot Beds unproved," as given for series E. in the Tabular 

 Column (Fig. 4) attached to the Report, it seems to encourage 

 the belief that, when the boring rod reached 215 feet from the 

 surface of the Worgret Hill plateau, 85 to 100 feet would be a 

 fairly liberal estimate of the thickness of the remainder of the 



