228 



HA RD WICKE'S SCIENCE- G OSSIF. 



ance appear on the north side of the river opposite 

 Borstal, where there are two faults showing a down- 

 throw ; whilst at Borstal itself a small fault, with five 

 feet upthrow, can be seen half-way down the escarp- 

 ment, the chalk there being false bedded, with very 

 wide cracks or fissures filled with rubbly chalk and 



session is thus treated, the plane of the cut showing- 

 tiny dendritic markings of manganese dioxide (?) 



At Blue Bell Hill the chalk is full of iron-stained' 

 fissures, the largest one being sixty feet deep, one 

 foot wide at the top, and filled with clay and debris. 



Between Borstal, Chatham, and Luton, there 



Fig. 133 — Pit at Luton, Kent. Upper chalk, 100 feet exposed ; 

 dip6"N.W. A, B, two similar very hard iron-stained chalk 

 layers of 2 feet thick, c, d, two fissures i to i inch wide. 



Fig. 134. — Upper chalk cuttin? on one side of London Road, 

 Luton, commonly known as Chatham Hill, i mile (ro:ii 

 locality shown in Fig. 13:1, and part of same escarpment. 

 Dip N.W., 36 feet exposed. B, continuation of lower iron- 

 stained layer shown in Fig. 133 ; E, faults ; F, cheek of flint. 



titSCAR.''MENT 



Fig. 135.— Lane at Luton, 48 feet exposed, dip 6*^ N.W. a, b, pipe, 

 36 feet in depth, containing Thanet sands, green-coated and ordinary 

 flints. Fossils very rare here. 



Fig. 136. — Ventriculite. 



rain-wash. The whole aspect of the pit is very 

 peculiar. 



At the Luton Pit there are several cracks from top 

 to bottom of the section, from J-inch to one inch 

 wide (Fig. 133). One remarkable feature about these 

 fissures is that the flints and fossils (principally 

 ananchytes) found on either side are split clean in 

 two as if by a gi.int knife. A niicraster in my pos- 



occurs, on the top of the chalk, a triangular layer, six 

 inches in depth, of chalk rubble re-cemented_by car- 

 bonate of lime, and probably some silica and iron, 

 while the chalk in the vicinity of New Brompton^ 

 near the river, is capped with Thanet sands, at the 

 base of which occur those peculiar unrolled flints 

 coated green with glauconite, about which Professor 

 McKenny Hughes and Mr. Whittaker oiTer such a 



