The country that has been the scene of our military operations against the Bhutanese extends over a distance, as troops march, of about 85 miles. A great part of this tract consists of almost impenetrable jungles and immense forests of sal trees, and, taken at the rate of 9 kos from the mountains, forms that strip that by the treaty is ceded to the Bhutanese. This country is intersected by numerous nullahs and small rivers, deep and rapid. The great rivers are the Tísta, Manshi, Tursa, and Baidak. All these rivers, the Tísta excepted, run in a south-eastern direction into the Brahmaputra, and are navigable for six months of the year as high as within 10 kos of the foot of the mountains; but their not communicating with the Ganges renders the fine timber on their banks but of little value. The produce of this strip, where cultivated, consists of rice, mustard seed, tobacco, some opium, and about 40,000 maunds of fine cotton annually; to the eastward it yields some black pepper and munga silk. The country, however, is extremely populous. The trade carried on with the Bhutanese is by way of barter. They pay little or no revenue to the Deb Rajah, and living easy under his government, are much attached to the Bhutan interest; and, indeed, from the nature of their situation, they can never be independent of it.