PART 4.] 
Mediicott: Note on the Geology of Nepal, 
95 
follows the liroad bed of a torrent, to near the very summit, where it turns up a steep gully, 
partly artificial. Here I noticed a strong bed of ochreous clay. A similar rock is very com¬ 
mon in a like position in the passes south of the Debra-Dun. Boulders of from 12 to 20 
inches cube are common in the bed of the torrent, though it is rare to see stones of this size 
in the conglomerate forming the cliffs on each side, from which, it would he assumed, all 
must he derived. Near the foot of the steep rise I observed a huge block of quartzite, 
measuring 10' X 7' X 6'. Deference to it will be made further on. 
In the Rapti, immediately under Etoundah, there are outcrops of the rusty sandy clays 
and greenish-gray sandstone at the base of the section north of the dun. They dip at 60° 
to north-by-east. Wherever observed along the road, this dip (with slight variation in amount) 
was found constant, and there is hut little change in the character of the rock. It is clearly 
an ascending section : clays occur, but very subordinately ; the sandstone becomes somewhat 
softer in the higher beds, and there are here several layers of thin conglomerate. In no 
single feature is there any precise resemblance to the series in the outer range. The strata 
closely correspond with the Nahan group of the north-west, and with that described by 
Mr. Mallet at the base of the Sikhirn Himalaya. At Etoundah the formation is about a mile 
wide, which would give an accumulated thickness of about 10,000 feet, there being nothing 
to suggest repetition by faulting or flexure. A blank covered space of fully 100 yards, 
between the last outcrop of the sandstone seen on the road section and the first outcrop of 
the slates, conceals the contact. It is probably, as usual, very steep, if not overhanging. 
Mr. Mallet has adopted for the Sikhirn ground the view I put forward regarding this main 
feature of the mountain-structure in the north-west, that it is not primarily a faulted rock- 
junction. There is no sign at the base of the section, nor as a remnant along the junction, 
ot any older tertiary rocks that might represent the eocene group of Subatlm. The inner 
limit of these sandstone hills is well marked by narrow longitudinal valleys of denudation. 
The first rocks seen north of the tertiary sandstone are some earthy schists, with a 
crushed dip of 50° to north-by-east, quite parallel in strike to the sandstone. A thin hand of 
blue limestone occurs in these beds, and further on a strong band of black schistose slate, 
in which are some irregular vein-like nests of impure carbonaceous matter. All these beds 
within a few hundred feet of the boundary, though decidedly subfoliated, are less altered 
than any rocks to the north of them, and also less highly- inclined. They are overlaid by 
more silicious rocks, flaggy schistose quartzite, nearly vertical, or folded in zigzag contor¬ 
tions. There is again a small appearance of more earthy schist, or possibly a reappearance 
of the former band, for tbe beds are greatly contorted, although the northerly underlie sooms 
constant. A trappoid rock occurs here; but its intrusive character is not well marked. It is 
the only rock of this kind that I observed in Nepal. The thin quartzites come in again and 
pass up into stronger beds of the same rock, which are overlaid by massive white crystalline 
limestone, all dipping at 70° to 80° to north-by-east. This limestone must he several hundred 
feet thick. The sample I brought with me is not dolomitic. At Bhaiusi Daman, where the 
river takes a bend, and above it for some miles, the rooks are much broken and confused. 
Great masses of the white limestone form irregular cliffs on both sides, the underlying rocks 
being concealed by vegetation and valley-deposits. 
It would seem as if the ascending section from the boundary to Bhainsi Daman here 
passed into a broad, broken and contorted synclinal basin. The east-by-soutk general strike 
is maintained throughout; it was observed in some quartzites a mile below Bimphcdi, which 
stands at the bead of tbe valley close under tbe steep ridge of Chessa-garhi. This glen of 
Nimbua-Tanr on the upper course of the Rapti is one of the most picturesque I have ever 
seen. 
