186 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [DeC. 1 7, 



Chemical Examination of the Waters. 



" No. 6. Water from the Lake of Ardchek, east of Van (at Ardcliek 

 village)." 



The reaction was slightly alkaline, and the water contained a minute 

 quantity of solid matter in suspension. The solid residue left on 

 evaporation evolved carbonic acid and traces of sulphuretted hydro- 

 gen, on the addition of muriatic acid. 



The specific gravity was 1*0212. 



" No. 7. Water from the Lake of Ardchek (from west extremity 

 of Lake)." 



The specific gravity was r0214. 



"No. 8. Water from Lake of Van at Merek." 



Reaction strongly alkaline, and the water contained traces of 

 suspended matter. It had no smell, and the specific gravity was 

 1-0187. 



" No. 9. Water from Lake of Van at Tad Van." 

 Specific gravity 1*0154. 



"No. 10. Chalybeate and saline water from a hot-spring, two 

 miles above Mershut village, up the Ardish Chai, north of Lake 

 Van. Supposed temperature 165° Fahr." 



Specific gravity 1*0028. The reaction was neutral, or very slightly 

 alkaline. The water evolved a smell of putrefying organic matter, 

 which was so persistent that it remained after evaporation to dryness 

 and remoistening with water. 



" No. 1 1 . Acidulated Saline Spring, two miles south of Bitlis. 

 Cold." 



Specific gravity 1*0019. Had a strong odour of sulphuretted 

 hydrogen, impregnated with decaying organic matter. Contained a 

 considerable quantity of gas, and reacted feebly acid. 



The whole of the waters were clear, except where we have men- 

 tioned having found traces of matter in suspension. The organic 

 matter appeared to contain no nitrogen, and no nitrates were present. 

 The proportion of gas was small, except in No. 1 1 . 



The small quantity of water at our disposal led us to boil each 

 sample and separate the precipitate by filtration. This precipitate 

 and the filtrate were then analysed in the usual manner. This mode 

 of analysis will explain why we have arranged the results of our ana- 

 lyses in the form which follows. 



This limited supply of water prevented us going more into detail 

 in the analyses, and determining with absolute certainty the absence 

 of iodine, &c. 



