TF. H. Hudleston — Creechharroiv in Purbeck. 151 



permitted us to ascertain whether there is any bedding in the 

 ' gravel.' The stones are of very unequal size, varying from flints 

 30 lb. in weight to quite small stones ; I did not at the time notice 

 any pebbles. The character of the flints here is just the same as in 

 all the Creechbarrow Beds ; the large ones have a partially "rounded 

 exterior consisting of white silica thoroughly degelatinized. Some 

 are degelatinized throughout, others have a brown core of gelatinous 

 silica still left ; most of them are very brittle and fly to pieces 

 on being struck by the hammer. At present it is not possible to 

 connect this particular bed of flints with those found in the pits 

 near the summit. That there are beds of flints occurring in 

 stratigraphical relation to the sands and clays of this hill is certain, 

 and they probably occur on several horizons. The manganese 

 nodules in the buff, ferruginous sand are very interesting and fairly 

 abundant. I shall refer to them again when dealing with the 

 lithology of the Creechbarrow Beds. 



The evidence obtained in this pit on the eastern spur goes to 

 confirm the supposition that the abundance of bedded flints of 

 Tertiary age in the upper part of Creechbarrow has materially 

 assisted the limestone in preserving the softer sands and clays from 

 denudation. Such an observation may be accepted as a general one, 

 applicable more or less to the whole hill. When we come to 

 particulars the limestone is more especially accountable for the 

 summit (A), whilst the unusual accumulation of flint 'gravel' is 

 more directly the cause of the eastern spur (B). 



3'. The Buff-coloured Clay. — Still dealing with the deposits 

 immediately below the limestone and ' marl,' we have seen that, on 

 the northern slope and some distance below the 500 feet contour, 

 the calcareous series rest on a few feet of sands with flint-gravel, 

 and that below this comes a very important deposit of buff-coloured 

 clay (Mr. Bond's clay-pit), which may occur as a lenticular mass, as 

 it does not appear to have any representative if followed in the 

 direction of the eastern spur. 



4. The lowest member of what I have termed the Creechbarrow 

 Beds are the ' Sands ' underlying the buff-coloured clay. These 

 can be studied at Mr. Bond's sandpit, where the following section 

 may be noted : — 



Creech Sandpit. 



ft. iu. 



a. Clay with rootlets ... ... ... ... ... ... 16 



b. Clay passing iuto sands ; flints occur, especially towards 



the base (? unconformity) 5 6 



c. Bedded sand 1 3 



d. Yellow clay with large flints at base and a pink line ... 10 



e. Yellow variegated sandy clay with a few small flints ... 16 

 /. Salmon-coloured sand with a black centre line, the colora- 

 tion probably due to manganese 3 



g. Very fine white sand with but little true bedding (not 



bottomed) 9 



20 



N.B. — a and h represent the base of the Creech brickearth or buff clay. 



