During our march towards Khara river, we struck the river _Boro_, a tributary of the Khara, which waters a fine broad valley containing the largest Mongol population we had seen anywhere collected in one place. As we followed the course of the Boro down the valley, we passed several apparently separate communities, all rich in cattle. A novel sight here met our eye, the cultivation of a coarse kind of rye, called by the Mongols, _boota_. They were harvesting this as we passed, carting it to the yourts in a rough sort of wooden cart, and stacking it up. This seems to show that the Mongols are not naturally averse to cultivation, when they are favourably circumstanced for carrying it out. Some of their tribes, such as those in Western Toumet, mentioned by Huc, do indeed systematically cultivate the ground. The sun had set before we got to the end of the valley, and we encamped in the evening not far from the left bank of the Khara-gol, sending out the lama with a native of the district to survey a crossing for the morning. Early on the 26th we advanced to the river at a place higher up than the usual ford. Carts were unloaded, and the passage effected in the same way as the Tolla, but, the river being much smaller, less time was lost in the operation. There is always a busy scene at these fords, particularly when a drove of cattle have to be got over. One poor man spent the whole morning in fruitless endeavours to drive half-a-dozen cattle through the river, but the neighbours at last came to his assistance, and led them through one by one. There was a steep pass before us, a few miles distant, and at a yourt near the Khara four sturdy little yaks were engaged to get our carts over. A young lama courier, well versed in the Russian language, whom we found in the yourt, where he had spent the night, afforded us no end of fun all the morning. He was a great wag, and affected to be a man of the world, travelling constantly as he did between the court of Peking and Kiachta. He chaffed our lama more than he liked, criticising his cattle, and offering to buy him out. As a specimen of how these couriers do their work, this young scamp had not only spent the whole night in a yourt, but waited in the morning for our party, and kept company with us till near mid-day. The pass is up a steep and rugged ravine, thickly wooded with white-skinned birch-trees. The trees do not grow to any size before they rot in the heart, and become hollow, when the wind blows them over. Few of them have a proper trunk, but two or three strong suckers shooting up from the root. It makes excellent firewood, but is unfit for any other purpose.