PART 4 .] 
Medlicoll: Note on the Geology of Nepal. 
07 
some single beds ave found low down. The schistose limestone of which the monoliths 
of Katmandu and Patun are made is quarried low down on the Kirthipur ridge at Choubal, 
where it is well seen at the gorge of the Baghmati. There are some thin bands of limestone 
also in the gorge at Pashpati. The prevailing rock is a peculiar massive, very fine schistose 
quartzite with a trifling percentage of carbonate of lime, yet to this minimum ingredient is, 
I believe, largely duo the physical condition of this mountain zone—its deep erosion, as chiefly 
exhibited in the basin of the Nepal valley. This rock is very prone to decompose, by the 
abstraction of the small calcareous element in it, and is therefore seldom found in clear out¬ 
crops. It is well exposed in the little stream at the north-west side of Sambunath. For 
the most part it forms at the surface an ochrey sandy clay. When only partially decomposed 
it forms what might be called a sandstone (freestone). In this state it is quarried at the base 
of Nagarjan for building. 
From the frequent reappearance of similar rocks across a broad zone of more or less 
vertical strata, one might of course presume that there is repetition by folding; but this 
condition is independently established: both Cliendragiri and Nagarjan ridges, and those 
flanking Phuleliok, are on synclinals. There would thus seem to be from the Pinouni into 
Nepal a repetition of the structural feature observed in the outer zone along the Kapti 
valley—an ascending section, only affected by minor foldings, through thinly bedded qnartzose 
schists into a broad many-folded synclinal, in which axr upper group of calcareous strata is 
frequently repeated at the surface. There is also sufficient likeness in the two series to suggest 
that they belong to the same formations, the most marked difference being the concen¬ 
tration of the calcareous element at the top of the southern section and its dispersion in the 
upper part of the northern one. 
I would further venture to suggest that this series may be the continuation of the 
Krol and underlying formations of the Simla region. The flaggy quartzites of the lower 
horizons in the Nepal sections would very fairly represent the thin silioious beds that form 
so large a part of the Simla slates, or infra-Blini zone. Cases have, moreover, been recorded of 
the Krol limestone being represented elsewhere by more or less calcareous sandstone : a re¬ 
lation quite analogous to that now suggested between the strong quartzite and limestone of 
Bhainsi Daman and the calcareous quartzites of Nepal. Katmandu is in about the same 
zone of the mountains as Simla and Almora, being only thirty miles in a direct line from the 
plains. There are two points of contrast between the section here and iu the Simla region, 
supposing the rocks representative : the contortion and the metamorphism of the strata in 
the latter position are local and partial, whereas in Nepal they are general and more or less 
complete. The limestone on the crest of the Chendragiri pass between Chitlong and Nepal 
is somewhat less altered than usual; in it I noticed some small facets of spar having a 
central puncture, and which I took to be crinoidal; but Dr. Waagen could not say positively 
tkat.they were so. 
On the north-north-east side of the valley the alluvial deposits rest against gneiss at the 
base of the Sheopuri range. The white patches so conspicuous along this edge of the valley 
are slip-faces in this rock where it is deeply decomposed. It is a coarse felspathic gneiss with 
much silvery mica and schorl. Its debris is a prominent ingredient of the valley deposits 
at Katmandu. On the spur north of Bodlinath and that connecting Sheopuri with Nage" 
jan, one finds very fine mica schists, first alternating with, and then succeeding to, the gneiss. 
The compression of the whole is so excessive and the underlie so variable, that it would he 
impossible to conjecture, without very detailed study, what the normal order of the strata 
maybe. On nearing Nagarjan the underlie sets towards it; but the flaggy quartzites of 
Chitlong, which certainly underlie the calcareous zone, are not specifically recognisable in the 
