TRANSACTIONS OF SECTION E. 583 
rock, succeeded by another of isolated low hills following the northern base and 
‘the course of the Brahmaputra, and generally lying to the north of it. The last 
outcrop is seen at Dhoobri, and thence it is no doubt continuous across the delta 
to similar outcrops of Bengal gneiss on the Ganges, thus connecting this axis of 
elevation with that of peninsular India. The above range is convex to the south, 
curving up to the N.E. in the Lhota Naga and Nowgong Hills, and to the 
W.N.W. in the Garo Hills. 
The Burrail range forms another subsidiary line of elevation to the above from 
the Naga Hills to Jaintiapur, and falls away dipping under the Sylhet bhzls,! to reap- 
_ at the most S.W. point of the Garo Hills. From its highest point in the Naga 
ills (Japvo), where the strata become nearly horizontal, it merges into and throws 
off the hich N. and 8. ridges that bound the Munipur valley on the west, to join the 
Lushai Hills on the south. This I would call the Western Munipur and Arakan 
range. It has no granitoid axis; but to the N.E. of Munipura great mass of 
intrusive rock occurs at the high peak of Shuruifurar, and thence a high line of 
elevation runs N.N.E. to Saramethi Peak, and to the south forms the eastern boun- 
dary of the Munipur valley, and might be called the eastern Munipur range. It 
is the water-parting between the above valley and that of the Kyangdweng. 
We can, in a measure, exemplify the structure of the Himalaya by that of the 
bones of the right hand, with fingers much elongated and stretched wide apart, of 
which the wrist and back may represent the broader belt of granitic rocks of the 
eastern area, the thumb and fingers the more or less continuous ridges of the N.W..,. 
some less prolonged than others to the north-west,such as the Chor axis, which may 
be represented by the thumb, terminating on the southern margin near the Sutlej. 
The left hand placed opposite will represent the same features to the west of the 
Indus. We will even carry this simile further, and as a rough illustration suppose 
the intervals or long basins between the fingers to be filled with sedimentary 
deposits, and the fingers then to be brought closer together, producing a crushing 
and crumpling of the strata. At the same time an elevation or depression, first of 
one or more of the fingers, then of another or of the whole hand has taken place, and 
you are presented with very much what has gone on upon a grand scale over this 
vast area. As these changes of level have not taken place along the whole range 
from E. to W. in an equal extent, but upon certain transverse or diagonal lines, 
undulations more or less great have been the result, and some formations have at- 
tained a higher position in some places than in others, producing, very early in the 
history of these mountains, a transverse system of drainage lines, leading through 
the long axial ridges. 
The last efforts of these rising, sinking, and lateral crushing, and, as I believe,. 
very slowly acting forces, are to be seen at the southern face of these mountains in 
the tertiary strata that make up the Sub-Himalayan axis (Sivalik), a topographical 
feature which is most striking by reason of its persistence and uniformity for some 
1,600 miles ; for, although a similar and synchronous elevation of the Alps has taken 
place, the same regularity of orographical features has not been the result, most 
probably from the difference in the original outline of deposition in the latter area. 
One object in this address will be to endeavour to point out and compare some of 
the physical features of the two great European and Asiatic chains, 
From Assam on the east to the Panjab on the west, bending round and extend- 
ing to Scinde, this fringing line of parallel ridges is found at the base of the 
Himalayas, sometimes higher, sometimes wider, often forming elliptical valleys. 
Only in one part of the belt east of the Teesta are they absent altogether, and 
for a distance of fifty miles the metamorphic rocks rise directly from the plains 
of India,” a feature representing a great break—the correct interpretation of which 
will tell us very much of the past history of these mountains. These formations 
are of vast thickness, and in the Panjab, where they attain their greatest width and 
elevation between the Chenab and the Indus, cover an area of 13,000 square 
tuiles. 
1 ¢ Bhil’ or ‘jhil’—Hind., a marsh. 
2 Godwin-Austen, J. A. 8S. B. 1867, p. 117. Memoirs of the Geological Society of 
India, Medlicott, vol. iv. pp. 392 and 435. j 
