After the border war of 1897 a narrow-gauge line was laid from Nowshera, on the Kabul River, to the foot of the Malakand; constructed in the first instance for military reasons, it rapidly developed into an important artery of commerce, justifying its conversion from a narrow to a broad gauge. Another railway which, in 1897, stopped on the left bank of the Indus at Kushalgarh, now crosses the Indus by a bridge, and has been extended via Kohat and Hangu to Thal, at the southern end of the Kurram Valley. A third line to the base of the hills is under construction; it will be taken over the Indus at Kalabagh and carried to Bannu. When the Thal railway has been extended to the head of the Kurram Valley; when a short line has been constructed in the Hazara district; and when a lateral branch has been provided from Bannu to Tank and Dera Ismail Khan, the province will be fairly well equipped with railways of a distinct commercial and strategic value. [Sidenote: Frontier Policy] A perusal of the chapters which follow will probably make it apparent that the general policy of the Government of India in regard to the frontier tribes is, and has been—as well described by a former Chief Commissioner of the North-West Frontier Province—“a forward one only when necessity compels, and stationary where circumstances permit.” CHAPTER II. BLACK MOUNTAIN TRIBES.[4] Before describing the Black Mountain itself and the various tribes which inhabit its slopes, it may be as well to say something about the country which encompasses it on three sides and about the men who occupy it. Allai is a valley bounded by Kohistan on the north and east, by the Bhogarmang Valley, Nandihar and Deshi on the south, and by the Indus on the west. The valley of Allai is divided from Kohistan on the north by a range of mountains rising to over 15,000 feet, and from Nandihar and Deshi by another range running from the British boundary to the Indus above Thakot. The average breadth of the Allai Valley is about twelve miles, and the total area about 200 square miles. Wheat, barley, Indian corn and rice are grown, and the mountain slopes at the eastern end are covered with forest. The men of Allai are ever engaged in internal quarrels; blood-feuds are rife, and often embroil the whole tribe. They are but little dependent on British territory; number some 9000 fighting men, indifferently armed; they have at times, although not of late years, given us some trouble, but have usually been coerced by means of a blockade, although a really effective one is not easy to enforce. [Sidenote: Surrounding Country]