GREEN OR CHLORITE SAND. 71 



roads*, and I know not in any country a better material. It is usually 

 disposed in irregular beds in the sandstone, but occasionally forms veins, 

 which intersect the strata ; I call the beds irregular, because they vary 

 much in breadth and appear not to continue far. 



"The Whinstone-j- shows a transition into the sandstone, and they 

 are certainly of contemporaneous formation. In some situations near 

 Petworth, great lenticular masses of this substance are imbedded in the 

 friable sandstone, and these follow the same sedimentary hne as the 

 beds of sandstone, although separated from each other by very wide 

 intervals : they are therefore unquestionably in situ. These masses 

 frequently measure eight or ten feet by two or three, and are invariably 

 surrounded by a more friable and ochraceous sandstone than the rest of 

 the strata." 



The Whinstone is sometimes traversed by veins of chalcedony, and 

 it also contains cavities lined with mammiUated concretions of the same 

 substance '^. 



At Parham, near the village of Storrington, and in the adjoining parish 

 of Rackham, the sand is highly ferruginous, and contains irregular con- 

 cretions of ironstone. These beds, which are peculiarly interesting from 

 the abundance and variety of their organic remains, were first noticed 

 by my brother, through whose kindness I have obtained a fine series 

 of specimens. 



In Parham Park, the seat of Lord De-la-Zouche, the sand appears 

 immediately beneath the turf, disposed in the following manner : 



1 . Surface soil, consisting of sand and vegetable earth ; in some parts 

 of a deep brown coloui*, approaching to black. 



2. A thin layer of ferruginous sand, with small nodular masses of 

 ironstone. 



* It was also noticed on Bexley Heath, and on the sides of Blackdown Hill, by Mr. 

 Lyell. ' 



■f- Whinstone, the name by which the chert is distinguished in Western Sussex, is probably 

 of Saxon origin ; it is unknown in the south-eastern part of the county. 



J This circumstance was communicated to me by the Rev. C. P. N. Wilton, M. .4. &c. of 

 Blakeney, Gloucestershire. 



