Fortunately for them, some 200 were now to leave these dismal surroundings and accompany me to the Tibetan frontier as escort. We marched on up the valley by a road carried in many places along the side of precipices overhanging the roaring river, and with neither wall nor railing intervening between one and destruction. Only in Hunza, beyond Kashmir, have I seen a more precarious roadway. The same luxuriant vegetation extended everywhere. But what impressed me most in this middle region of Sikkim were the glorious waterfalls. Never anywhere have I seen their equal. We were in the midst of the rains. The torrents were full to the limit, and they would come, boiling, foaming, thundering down the mountain-sides in long series of cascades, gleaming white through the ever-green forest, and festooned over and framed with every graceful form of palm and fern and foliage.
And now, as we reached the higher regions, the loathsome leeches, the mosquitoes, gnats, and midges, were left behind, and we came into a region of Alpine vegetation—spruce-firs, ash, birch, maple, crab-apple, and nut, with jasmine, ivy, spiræa, wood-sorrel, and here and there, rising lightly through the shade of the forest, a gigantic white lily, most exquisitely lovely.
On June 26 we reached Tangu, at a height of 12,000 feet above the sea, and here in a comfortable wooden rest-house, in a cool and refreshing climate, we were able to forget all the depressions of the steamy valleys. The spiræa, maple, cherry, and larch, which we had met lower down, had now disappeared, and in their place were willow, juniper, stunted birch, silver fir, white rose, berberry, currant, and many rhododendrons. The mountain-sides were covered with grass and carpeted with flowers, and especially with many beautiful varieties of primulas, as well as with gentians, potentillas, geraniums, campanulas, ground orchids, delphiniums, and many other plants, while near by we found a fine dark blue poppy; and, most remarkable plant of all, growing here and there on the mountain-side in isolated grandeur, a gigantic rhubarb (_Rheum nobile_), described by Hooker as the handsomest herbaceous plant in Sikkim, with great leaves spread out on the ground at the base, while the main plant rose erect to a height of 3 feet in the form of a pyramid, but with the clusters of flowers protected from the wind and rain, by reflexed bracts.