Camp on Zemu river -- Scenery -- Falling rocks -- Tukcham mountain -- Height of glaciers -- Botany -- Gigantic rhubarb -- Insects -- Storm -- Temperature of rivers -- Behaviour of Lachen Phipun -- Hostile conduct of Bhoteeas -- View from mountains above camp -- Descend to Zemu Samdong -- Vegetation -- Letters from Dorjiling -- Arrival of Singtam Soubah -- Presents from Rajah -- Parties collecting Arum-roots -- Insects -- Ascend Lachen river -- Thakya-zong -- Tallum Samdong village -- Cottages -- Mountains -- Plants -- Entomology -- Weather -- Halo -- Diseases -- Conduct of Singtam Soubah -- His character and illness -- Agrees to take me to Kongra Lama -- Tungu -- Appearance of country -- Houses -- Poisoning by arum-roots -- Yaks and calves -- Tibet ponies -- Journey to Kongra Lama -- Tibetan tents -- Butter, curds, and churns -- Hospitality -- Kinchinjhow and Chomiomo -- Magnificent Scenery -- Reach Kongra Lama Pass. My little tent was pitched in a commanding situation, on a rock fifty feet above the Zemu, overlooking the course of that river to its junction with the Thlonok. The descent of the Zenlu in one thousand feet is more precipitous than that of any other river of its size with which I am acquainted in Sikkim, yet immediately above my camp it was more tranquil than at any part of its course onwards to the plains of India, whether as the Zemu, Lachen or Teesta. On the west bank a fine mountain rose in steep ridges and shrubby banks to 15,000 feet; on the east a rugged cliff towered above the stream, and from this, huge masses of rock were ever and anon precipitated into the torrent, with a roar that repeatedly spread consternation amongst us. During rains especially, and at night, when the chilled atmospheric currents of air descend, and the sound is not dissipated as in the day-time, the noise of these falls is sufficiently alarming. My tent was pitched near the base of the cliff, and so high above the river, that I had thought it beyond the reach of danger; but one morning I found that a large fragment of granite had been hurled during the night to my very door, my dog having had a very narrow escape. To what depth the accumulation at the base of this cliff may reach, I had no means of judging, but the rapid slope of the river-bed is mainly due to this, and to old moraines at the mouth of the valley below. I have seen few finer sights than the fall of these stupendous blocks into the furious torrent, along which they are carried amid feathery foam for many yards before settling to rest. Across the Thlonok to the southwards, rose the magnificent mountain of Tukcham, but I only once caught a glimpse of its summit, which even then clouded over before I could get my instruments adjusted for ascertaining its height. Its top is a sharp cone, surrounded by rocky shoulders, that rise from a mass of snow. Its eastern slope of 8000 feet is very rapid (about 38 degrees) from its base at the Zemu river to its summit.