296 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



tine, porphyry, and granitic compounds, in mass and in veins, — a 

 splendid field for the mineralogist with time at his disposal. 



On the descent to Lahijan, the igneous rocks are again concealed by 

 the appearance of the slates and altered limestone. Undulating hills 

 of the latter traverse the plain of Lahijan in every direction, and rise 

 in little rounded hillocks in its centre. The strata exhibit much con- 

 tortion, and are traversed by threads of carbonate of lime. 



Kiih i Komarend, which separates the sources of the Zab and the 

 Gader, is an offshoot from the great chain of the Frontier. The 

 blue limestone is here converted into cream-coloured and purely 

 white marble, resting unconformably on a mass of stratified, mica- 

 ceous, grey schist. Quartz and felspar are irregularly interspersed in 

 layers in the midst of a matrix of finely-grained mica. This rock 

 cleaves into beautiful regular, elongated, rectangular parallelopipeds, 

 sometimes contains crystals of pinkish felspar, and passes downwards 

 into a finely-grained granite. 



To theN.W. of this range are a series of low limestone-hills skirt- 

 ing the plain of U'shnii. 



Kel i Shin Pass. 



The height of this Pass above the sea is stated by Mr. Ainsworth 

 (Journal of Roy. Geogr. Soc. vol. xi. p. 62) to be 6000 feet, but at 

 p. 64, and in the section annexed to the memoir he gives it an eleva- 

 tion of upwards of 10,568 feet. 



Unfortunately all the barometers of the Commission were broken 

 soon after reaching the mountain-districts, so that we had no means 

 of ascertaining which measurement is the correct one. At a guess, 

 it is, I should imagine, 10,000 or 11,000 feet above the sea-level, the 

 higher peaks of the range being 2000 feet more. 



Various rocks show themselves on the descent from the N.E., and 

 of these the following were noted whilst we were ascending : — 



Altered blue limestone, with veins of carbonate of lime. 



Red iron-clay, with serpentine. 



Dark blue serpentine, with veins of steatite. 



White quartzose rock. 



Decomposing, fine-grained, white granite. 



White quartzose rock, with grey serpentine. 



At the summit, a few paces from the celebrated pillar (with the 

 cuneiform inscription) which gives its name to the Pass, is a rock 

 dipping at an angle of 45° to the east, presenting an ascending 

 section as below : — 



Light green serpentine. 



Red indurated clays, approaching to jasper, and containing iron- 

 stone. 



Dark-grey quartzose rock, weathering rusty-brown. 



A vein of very dark-green and hard serpentine traverses the line 

 of bearing between the two first-named rocks. 



The pillar itself is cut out of a hard hornblendic rock, with long 



