LA DAK. 
57 
complaining of headache, and I found several of the 
Tibetan porters lying in the road completely pros- 
trated. When asked what was the matter, they 
placed one hand across the forehead, and with the other 
plucked up a piece of a strong-scented Artemisia, 
making signs that this plant was the cause of their 
suffering. On some of the passes the Artemisia has an 
overpowering odour, and everything, baggage, horses, 
and men coming from Yarkand stink of it. We used to 
think even the mutton had the same flavour. Several 
travellers have told me that they and their followers 
suffered more in crossing this pass than on much higher 
ones. We encamped for the night at a pretty little 
lake of sweet water, 300 feet below the level of the 
top of the pass. The unpleasant symptoms, caused by 
the rarity of the air, did not disappear until the day 
after, when we reached a much lower altitude. I myself, 
even at 19,600 feet, have never experienced much 
discomfort, beyond a little shortness of breath after 
active exertion, and occasionally awaking during the 
night with a feeling of suffocation, which usually 
passed off after a few deep inspirations had been taken. 
With several of our party the symptoms were very 
severe, and at times even alarming. There was 
intense headache and great prostration of mind and 
body, with constant nausea, and such irritability of 
the stomach that even a spoonful of cold water could 
not be retained. Great irritability of temper was 
another marked symptom, and in some cases the 
lips became blue ; in Mr. Shaw's case a clinical 
thermometer showed a fall of temperature from one 
to two degrees, compared with his temperature on 
previous days. I happened to have amongst my 
