PART 4.] 
McMahon : The Simla Himalayas. 
211 
and which must, I think, be a Krol rock. Below it (I examined the descending series 
for about 1,500 feet in vertical height) are carbonaceous shaly schists and slaty schists which 
become somewhat ckloritic. Above the limestone are silicious and garnetiferous mica-schists, 
which possibly belong to the “ central gneiss” or crystalline series of rocks, and if so, we have 
here an instance of the extreme unconformity 1 believe to exist between these two great 
divisions of our rock-series. 
I return now, after this digression, to the Blaini rock left in the Shallu Biver 3,000 feet 
below. The Blaini beds there dip north-west at a considerable angle and are repeated two 
or three times by contortion. On the ascent up to Chepal, the dip drops to 15° north- 
ll°-west and north-north-west. At Chepal the dip is north. The rocks on the Chepal, 
Paternalla (Patanala) and Dalia (Dhar) ridges, along which the Mussurie and Simla road 
winds, have been conjecturally identified (l. c. p. 41) as the Infra-Krol and Boileaugunj 
(Krol quartzite) series. If this view is correct, and I feel sure it is, the Blaini rocks must 
pass under these schists and ought to crop out between Dhar and the Giri. Accordingly 
where the road crosses the Chota Nadi (the stream which flows down from Patanala past 
Ghodna to the Giri), I observed numbers of boulders of the Blaini conglomerates in the bed 
of the stream. 
I availed myself of the first opportunity I could get to search the bed of the Chota 
Nadi for the Blaini rocks, and I found that the conglomerate cuts across its bed about 2 
miles above the bridge on the Dhar and Simla road. The conglomerate exactly resembles 
the conglomerate below Chepal. There are the large pebbles or boulders of the dark 
quartzite answering to the slate-grit of the Simla sections; and there are the white quartz 
eggs which in this section at times, as in the Ussan River, form a prominent feature of the 
rock. Not far from the conglomerate I found a thin bed of limestone. From this point 
the conglomerate crops out freely, rising gradually from the river, and rounding the spur 
facing Tikera* (Sanj), whence its course is up the left or east side of the valley of the Giri, 
I met several outcrops of limestone along this section. I left the conglomerate in cliffs high 
up on the east side of the valley, and as it was clear from the run of the strata that it must 
soon strike down to the Giri, I continued my search for it along the bank of that river. I 
found that it cuts across the Giri about If miles on the Sanj, or south, side of Bagain. The 
slates are here perpendicular, and those on both sides of the conglomerate have a black 
streak which appear to indicate that the Blaini rocks have been jammed into the Infra- 
Krol slates. The boulders in the conglomerate are well rounded, and in places are so 
loosened by the action of water that it required a careful inspection of the rock to satisfy 
me that I was not looking at river boulders entangled in cracks in the slates; but after a 
deliberate examination of the rocks, I felt satisfied that I had got hold of my old friend. 
Above the conglomerate the rocks are dark slates, till about one-third of a mile beyond 
Bagain,f where mica-schists begin. After this there are mica-schists and silicious schists all 
the way to Kot (Kot KhaiJ). They are an exact counterpart of similar rocks at Simla, 
and clearly belong to the Infra-Krol and Boileaugunj (Krol) series. The average dip is 
east-north-east, sometimes 34°, at other times low. Below the conglomerate the rocks are 
Simla slates all the way along the road to Tikera (Sanj). 
III.— Maiiasu, Mattiana, and Shah Hills. 
Our starting-point for this excursion shall be Thiog. The old Mattiana road rises to 
the fort of Thiog (a fort on a peak to the north of the Dak Bungalow), keeps along the 
* There may be a village of this name, but Sanj is the name by which this halting place is known to Natives and 
Europeans. 
t Bagain is on the road somewhere between Shilo and Choal of the map. 
t Kot Khai is the principal town of the tract of country marked Kot Khai in large letters in the map. It is on 
the upper Giri. 
