I had not seen one of these kangs before and the method of heating it had not been explained to me, so, the cold being intense, I placed fresh fuel on the smouldering embers the last thing before turning in. How long I had been asleep I do not know before I became conscious of a frightful nightmare. I was very hot and had lost all power to move. My tongue felt swollen and heavy, and my throat so dry and sore that when I tried to cry out it refused to utter a sound. My eyes were smarting, and having once opened them they would not close again. My senses were clear and I knew that I was being asphyxiated, but was powerless to help myself. Horror-stricken, I watched the bright moonlight shining on the paper window until I lost consciousness. The next thing I remember was cold air beating on my face, water in my mouth and trickling down my neck and chest, strong arms supporting me and the voice of my friend's mafoo calling to his master for a light, the moon having set. I owed deliverance to the fortunate breaking of my pony's halter, as, having been freshly clipped, he had become restive from the cold, thereby causing the mafoo to enter my room for a spare one, which I always carried with me. The following morning I felt very shaky and had a splitting headache, but was able to continue the journey, gradually recovering as the day wore on. It is perhaps needless to add that putting fresh charcoal on the fire was the cause of this _contretemps_, but I was then unaware of there being no flue to carry off the fumes. Leaving our ponies and the cart at Yang Fang, and mounted on mules as being more surefooted, though the high wooden saddles and short stirrups were most uncomfortable, we started betimes. After crossing a plain about ten miles in width, strewn with rocks and boulders, we reached Nan K'ow, or Southern Pass, where we entered the mountains. The road was fairly good for pack-animals, although crossed at frequent intervals by the beds of partially-frozen streams, the swift-flowing waters of which were sweet and clear as crystal. Mountains shut us in on either side, while we met an unending procession of men and beasts conveying loads of merchandise from Mongolia to Peking. The scenery was lovely, and all along the route were to be seen crumbling forts and walls built many centuries ago to defend this, the principal pass, against invading enemies. We saw three or four pheasants and heard several more, so that there probably is good sport to be had amongst these rugged hills. After halting for tiffin under a fine archway of Indian architecture we arrived at Pa-Ta-Ling (eight lofty peaks), where we obtained a good view of the Great Wall. Scrambling to the top at a place where it was partly in ruins, my friend was soon busy with his camera, whilst I proceeded to investigate this world-famed structure.