84 
SECOND YAKKAND MISSION, 
parallel secondary chain. Between the two the palaeozoic rocks rise to a considerable elevation, forming 
synclinal and longitudinal valleys. We shall follow the section to the north-east, from the foot of the principal 
ridge, according to Severtzofhs latest accounts, and begin at the Naryn River, the valley of which is bounded 
on the south by an outer range of the Thian Shan, the Chakir-tau. This consists of granite and mica schist, 
the opposite slope of the valley being entirely composed of contorted clay-slate, which locally, overlaid by dark 
violet porphyry conglomerate, extends to the north-west to the top of the Sari-tau, in which, at the pass of 
Barskoum, syenite is exposed. 
cc Proceeding from this pass towards Lake Issik diorite and serpentine are first seen; then mountain 
limestone, which forms a synclinal. This synclinal coincides with the longitudinal valley separating the Sari-tau 
from the next range to the north, the Terskei-Alatau, and this latter corresponds to the Sari-tau ridge 
precisely, so that, on the north side of the intervening valley, first mountain limestone with the slope reversed, 
then diorite, and finally syenite, are met with. Below, on the shores of Issik-kul, sandstone is found, which 
may be compared with the carboniferous strata of the Kara-tau . 1 At the eastern end of Issik-kul the little 
range of Kisil-kija 2 consists of red argillaceous sandstone; this range lies nearly in the direction of the 
greatest (longitudinal) diameter of the lake itself, and in the line of strike of the Rothliegende at the western, 
end of the lake, in the gorge of the Boam stream and on the northern slopes of the Khighiz Alatau . 3 
Proceeding over the Santash pass into the region of the Trans-Ri-Alatau, this is found to consist of granite 
intersected by two or more bands of limestone standing at high angles or bent into trough-shaped curves; one 
of these bands forming the ridge between the rivers Chilik and Chanishk. 
“ Finally, the granite northern slopes of the Trans-Ili-Alatau, as already stated, are terminated, towards the 
north, by a long but rather low chain of hills which consist of porphyry/'’] 
1 North of Chemkend and Tashkend. | 2 Tasma mountains on some maps. 
3 Now called on many maps Alexandrovski range. 
