Until late in April all the plain was intersected by frozen streams. Blankets were stripped from the mules to make a pathway for them over the ice. Often they went without water at night, and at mid-day, when the surface of the ice was melted, their thirst was so great that many died from overdrinking.
Had the Tibetans attacked us in January, they would have taken us at a great disadvantage. The bolts of our rifles jammed with frozen oil. Oil froze in the Maxims, and threw them out of gear. More often than not the mounted infantry found the butts of their rifles frozen in the buckets, and had to dismount and use both hands to extricate them.
I think these men who took the convoys through to Tuna; the 23rd, who wintered there and supplied most of the escort; and the 8th Gurkhas, who cut a road in the frost-bound plain, may be said to have broken the back of the resistance to our advance. They were the pioneers, and the troops who followed in spring and summer little realized what they owed to them.
The great difficulties we experienced in pushing through supplies to Tuna, which is less than 150 miles from our base railway-station at Siliguri, show the absurdity of the idea of a Russian advance on Lhasa. The nearest Russian outpost is over 1,000 miles distant, and the country to be traversed is even more barren and inhospitable than on our frontier.
Up to the present the route to Chumbi has been viâ Siliguri and the Jelap and Nathu Passes, but the natural outlet of the valley is by the Ammo Chu, which flows through Bhutan into the Dooars, where it becomes the Torsa. The Bengal-Dooars Railway now extends to Madhari Hat, fifteen miles from the point where the Torsa crosses the frontier, whence it is only forty-eight miles as the crow flies to Rinchengong in the Chumbi Valley. When the projected Ammo Chu cart-road is completed, all the difficulty of carrying stores into Chumbi will be obviated. Engineers are already engaged on the first trace, and the road will be in working order within a few months. It avoids all snow passes, and nowhere reaches an elevation of more than 9,000 feet. The direct route will shorten the journey to Chumbi by several days, bring Lhasa within a month's journey of Calcutta, and considerably improve trade facilities between Tibet and India.