The prices that different articles fetch at these auctions is often amazing. The demand of course depends on whether the force as a whole has grown short of the particular article now for sale, and whether it can or cannot be obtained by the individual through the post. Beyond Gyantse there was no regular parcels post, so that of many articles we were feeling a keen want. Accordingly, a few sheets of note paper and a few envelopes held up in the hand as one enticing 'lot' would on that occasion fetch two rupees. At another similar auction I remember half-pounds of tobacco going for five rupees each, and one-rupee packets of 'Three Castles' cigarettes also for five rupees. CHAPTER XVIII THE END OF THE CROSSING: THE 'CHIT' IN TIBET The Sappers and Miners, the coolis, the boatmen, the various units employed on fatigue, and the mule drivers must have been heartily glad when the crossing was all over. We were leaving both yaks and donkeys behind here (to work with convoys between Gyantse and Chaksam), so that we did not have to accomplish the feat of embarking and disembarking these somewhat clumsy animals; but even so, the amount of labour that had been involved was immense. I am told that, at any rate in Indian frontier warfare, there has hitherto been no instance of a force of this size crossing a river of this dimension without the aid of a pontoon bridge (the materials for which it would have been impossible on this occasion to carry with us). Further, the actual breadth of the river gave no idea of the difficulty of crossing it. The swiftness of the current, the whirlpools, and the speed with which the river, fed as it was by mountain streams, rose and fell, constituted the main difficulties. Further, in addition to the main channel which was the chief obstacle, there was a second channel beyond it, which, though not wide and sometimes fordable, constituted an additional delay to the crossing. As the last boatload crossed, the river was rising fast, and I am told that the amount of spare material left at the ends of the long rope, which was the main factor in swinging the large boats across without letting them drift down-stream, could be measured by the inch. Another inch or so in the rise of the river, and a corresponding widening of the stream, would have left that rope all too short for the work it had to accomplish, and our crossing might have been indefinitely delayed, for afterwards the river still continued rising. We left the Tsangpo fairly well stocked with provisions. During the march of forty-five miles to Lhassa we were informed that we should come across all that we required. The road from North Chaksam followed the course of the river for three miles; then, taking a sharp turn to the left, entered another wide valley watered by another river, the course of which we were to trace up-stream as far as Lhassa.