SON PLATEAU. 237 



beds and the "red marl" beneath. Returning" to the main gorge, the 

 lower portion of it still exposes the red salt-marl, rising considerably above 

 the bed of the stream, the occurrence of salt being indicated by a chowhi. 

 Here the path to Amb leaves the bottom of the glen and ascends a steep 

 hill of limestone (the ascent having given a barometric depression of '6 of 

 an inch by aneroid) ; after which a slight descent leads into the smaller 

 valley within which that village is situated. The fault which longi- 

 tudinally traverses this smaller valley branches in 

 Amb village. 



. the neighbourhood of the village so as to include 



a wedge-shaped mass of the " speckled sandstone '^ gi'oup, having on one 

 side the '' red marl '' upon which the village stands, and on the other a 

 portion of a basin of the Jurassic, triassic, and carboniferous rocks. The 

 red marl is gypseous and stratified, dipping towards the north-east at 40° 

 to 50°, and just above it only the lower or shaly portion of the "purple 

 sandstone^^ is represented. The succession of the beds at the village is 

 as follows : — 



6. Caebonifeeous . . . Carboniferous limestone. Feet. 



[ Grey clays, yellow partings .,, ... ... 40(?) 



j Wbite sandstones, weathering greenish ... ,.. 79 



' I Greenish shaly lavers and conglomerates of meta- 

 STONE ... I J J o 



L morphic pebbles ... ... ... 50(?) 



'' Grey lumpy, sandy, shale ... ... ... 1"5 



2. PUEPLE SAND- I .^ , , , . , , ^^ , , „ 



STONE ^ Dark purple and greemsn clay ... 80 to 100 



(^ Purple flaggy shale ... ... ... 100 



r Compact white gypsum ... ... ... 25 



1. Salt-mael .,,.{ Grey and red shaly marl ... ... ... 4 



l^ Red salt-marl, gypsum veins ... ... ... 70 



The representatives of the " purple ^^ and " speckled ^^ sandstones (No. 3 

 Change in the Purple ^^^ ■^*^' ^) extend up the valley in an east-south-east 

 Sandstone group. direction, until they disappear beneath the car- 



boniferous limestone. A fractured segment of a basin containing newer 

 rocks than these lies below Amb, along the stream on the northern side 

 of which the village stands. From the heights above the village the 

 carboniferous limestones may be seen on the opposite hill-side dipping 

 in northerly directions, and passing beneath the newer and softer beds 

 along the course of the stream. 



( 337 ) 



