LOWEK GREENSAND. 45 



It will be noticed that the source of the Medina at Chale Green 

 is situated on the upper of these two terraces. The valley of the 

 river gains in depth northwards, while the strata, except for some 

 very gentle undulations, remain horizontal. It is probable that the 

 depth thus gained is sufficient, to let the stream reach the " foliated 

 sand and clay," and that this may account for the width of the 

 alluvial flat ; but there is no section to prove it. The hills are 

 capped by bitff and white sand, while their sides are formed of 

 brown and grey sands with an occasional seam of iron-oxide. 



The Sand-rock Series is exposed at Chale Farm, Gotten, and 

 at the north end o£ St. Catherine's Down, with its usual character 

 of fine soft white sand. But its outcrop, though broad, is partly 

 overspread by Gault, which, owing to the influence of percolating 

 water, has flowed down ovei' the intervening Carstone. 



We now enter the drainage area of the (East) Var. Blake 

 Down, here forming the watershed between this river and the 

 Medina, is a long spur of the uppermost beds of the Ferruginous 

 Sands, capped Avith flint-gravel. As the river is about 100 feet 

 below the highest strata of this spur, the ^' foliated sand and 

 clay " might be expected to be reached. There can be little 

 doubt that this is the case, for a terrace, closely resembling that 

 of Pyle, Corve, and Kingston, runs through Godshill, north of 

 SandiEord, towards Lessland, and perhaps to Branston. From 

 the foot of the bold brow which terminates this terrace at Gods- 

 hill springs wander through wide peaty marshes, as at Corve, 

 while the brow itself is composed of a ferruginous sand and 

 greyish green sand, exposed to considerable depth in the road- 

 cuttings. 



The lower beds of the Sand-rock Series are seen in a pit near 

 Sibbecks, which gives the following section : — 



Feet. 

 Soft sand ^vith seams of clay - - . - 20 



Soft yellow and white sand-rock (perhaps the third 



sand-reck of Fitton) - - - - - 18 



Thin-bedded yellow and white sand with brown loamy 



partings --_... g^ 



Similar beds are seen in l,he grounds of Wydcorabe, Red hill, 

 Fairfields, and under the gravel at Ford Farm. Near Itchall 

 a pit exposes the top of the series, namely, white sandstone, 

 more than fifteen feet thick, overlain by eight feet of Carstone. 

 The base of the series is difficult to fix throughout the neio-hbour- 

 hood of Chale Green, but a blue clay seen in the brook south 

 of Roud, in the lane at Russell's Farm, and in the high-road 

 north-east of this farm, is presumably the same bed which we 

 have already noticed at the top of the Ferruginous Sands at 

 Slianklin. 



The characteristic scenery produced by the Sand-rock Series 

 and the overlying Carstone is admirably shown around Sainham 

 and Godshill Park. The base line of the Carstone, the beds being 

 nearly horizontal, meanders round a number of short but deep 



