J. F. CAMPBELL ON GLACIAL PERIODS. alah 
casus: after the water has run down from the hills, it gathers into 
four chief streams, which run east and west along the base of the 
hills as a gutter does under the eaves of a steep roof. All that I 
have been able to learn about the geology of these two mountain- 
ranges shows that wearing by rains and rivers is guided by the 
slope, but it is modified in direction by the structure of the rock, 
which is carved accordingly. The Geological Survey of India is not 
completed ; but, so far as I am informed, the Himalayan ridges and 
furrows are carved out of beds which are much crumpled and faulted, 
and which include sedimentary fossiliferous rocks of many periods, 
recent and very old, from Tertiary rocks to Silurian shales. Recur- 
ring earthquake-waves may have something to do with the joints and 
cleavage and fracture of these rocks. 
The Work of Rivers.—I had no local maps; I could get none of 
the district at the office of the Great Trigonometrical Survey of India, 
which is at Dehra. I was there referred by the Directors to Cal- 
cutta. When I got unfinished maps there, the area drained at 
Hirdwar is roughly a figure bounded by a quarter of a circle, with 
aradius of about 80 miles. The edges of this ribbed saucer are 
‘“‘snowy peaks” and a zone more than 20,000 feet high. Glaciers 
are marked on the maps about the edge of this hollow. Most of 
them are on the north side, towards the Sutlej. 
It is the custom of surveyors in a mountain country to follow 
levels and to draw contour lines. Sheep-paths and goats’ tracks and 
bridle-paths are laid out on the same principle. A sea-coast is a 
“contour line,” and roads in the Himalayas wind about in search of 
a level to walk upon. A straight course would be a continual climb 
up or down. In the ‘ General Report on the Operations of the Great 
Trigonometrical Survey of India during 1874-75,’ at p. 46 (23), 
“ Kumaun and Garhwal Survey,” Mr. F. C. Ryall, the reporter, di- 
vides his district into zones or belts, which are, as I suppose, tracts 
of country between “‘ contour lines.” These “ belts” surround the 
headwaters of the Ganges and neighbouring basins towards Nepal. 
The watershed which I saw, and sketched from a distance, is a sierra 
of peaks, comparable to the Lofoten Isles in Norway for sharpness. 
Beyond that ridge is the Sutle], flowing westward over high undu- 
lating ground, on a steppe which has been seen by the surveyors. 
The river plunges suddenly down from the frontier. One of the 
surveyors, Mr. Pocock, got to a height of 22,040 feet; another 
spoke of a friend who had reached to 24,000 feet. These exalted 
persons saw a great deal of the world with practised eyes, and I re- 
spect them and their information greatly. 
§ 1. The first zone on the Indian side of the watershed is about 15 
miles wide. The ground there undulates, as it does in Thibet. The 
land is utterly barren, very cold, and glacial. In that mountain 
region river-basins and minor ridges average from 14,000 to 
20,000 feet above the sea-level. In all mountain countries known 
to me there is a region of “high Alpine valleys” near the water- 
shed, in which water flows slowly, on gradual slopes. Contour lines 
drawn at regular intervals of altitude are wide apart. These are 
