From Ralung the valley widens out, and the country becomes more bleak. We enter a plateau frequented by gazelle. Cultivation ceases. The ascent to the Karo Pass is very gradual. The path takes a sudden turn to the east through a narrow gorge.
On the 17th we camped under the Karo la in the snow range of Noijin Kang Sang, at an elevation of 1,000 feet above Mont Blanc. The pass was free of snow, but a magnificent glacier descended within 500 feet of the camp. We lay within four miles of the enemy's position. Most of us expected heavy fighting the next morning, as we knew the Tibetans had been strengthening their defences at the Karo la for some days. Volleys were fired on our scouts on the 16th and 17th. The old wall had been extended east and west until it ended in vertical cliffs just beneath the snow-line. A second barrier had been built further on, and sangars constructed on every prominent point to meet flank attacks. The wall itself was massively strong, and it was approached by a steep cliff, up which it was impossible to make a sustained charge, as the rarefied air at this elevation (16,600 feet) leaves one breathless after the slightest exertion. The Karo la was the strongest position on the road to Lhasa. If the Tibetans intended to make another stand, here was their chance.
In the messes there was much discussion as to the seriousness of the opposition we were likely to meet with. The flanking parties had a long and difficult climb before them that would take them some hours, and the general feeling was that we should be lucky if we got the transport through by noon. But when one of us suggested that the Tibetans might fail to come up to the scratch, and abandon the position without firing a shot, we laughed at him; but his conjecture was very near the mark.
At 7 a.m. the troops forming the line of advance moved into position. The disposition of the enemy's sangars made a turning movement extremely difficult, but a frontal attack on the wall, if stubbornly resisted, could not be carried without severe loss. General Macdonald sent flanking parties of the 8th Gurkhas on both sides of the valley to scale the heights and turn the Tibetan position, and despatched the Royal Fusiliers along the centre of the valley to attack the wall when the opposition had been weakened.
Stretched on a grassy knoll on the left, enjoying the sunshine and the smell of the warm turf, we civilians watched the whole affair with our glasses. It might have been a picnic on the Surrey downs if it were not for the tap-tap of the Maxim, like a distant woodpecker, in the valley, and the occasional report of the 10-pounders by our side, which made the valleys and cliffs reverberate like thunder.
The Tibetans' ruse was to open fire from the wall directly our troops came into view, and then evacuate the position. They thus delayed the pursuit while we were waiting for the scaling-party to ascend the heights.
A. Gurkhas line of Adv.
B. Rocks occupied by enemy finally dislodged by Gurkhas.