Arras was formerly a beautiful little city, but it stands on the edge of perhaps the ugliest stretch of country on earth. Ten miles north of it is the town of Lens, south of which the Black Country of France begins. I have already told you that the Sambre cuts through an important coalfield. This coalfield is continued west into North France as far as the right bank of the Lys. The area of the coal-bearing region in Pas-de-Calais is about 240 square miles, and its yield is about twenty million tons per annum, which is about one-half of the total yearly output of France, but not a twelfth part of the annual production of Great Britain. You may be sure that this coal-bearing area is a busy and grimy region of pits and factories, much like the coal-mining parts of Lancashire or the West Riding of Yorkshire. There are the same straggling towns of mean houses merging into one another, the same mounds of refuse topped by the head-gear of pits, the same dirty roads, the same factory buildings, and the same criss-cross of railways and canals. The Lys, like the Irwell and the Aire, is black and foul with the grime of industry. Béthune, which may be said to mark the western limit of the coalfield, has numerous pits in the neighbourhood, and a variety of industries such as are usually found in towns similarly situated. It stands twenty miles west-south-west of Lille, and is connected with it by an important canal which runs almost directly east to La Bassée for about seven miles. Beyond La Bassée the canal continues its eastward course for another four miles, and then unites with a canal system running north-eastward to Lille. Along both sides of the canal there are important railway lines connecting Lille with Béthune and the Channel ports. La Bassée is a small manufacturing town of 4,800 inhabitants, with no special features to distinguish it from dozens of others in this industrial region, but owing to its military importance in the present war it will henceforth enjoy a fame which many a city of old renown might envy. You already know that the canal from Béthune to La Bassée was chosen as the dividing line between Maud'huy's army and the British forces. The point where two Allied armies join hands is always considered to be the weakest part of any defensive position. You will learn, as the story proceeds, that the Germans made the most determined efforts to break through the sally-port of La Bassée, and that the British strove with all their might to push through the German lines in the same neighbourhood, so as to cut the railway by which the enemy was able to move his troops rapidly from north to south, and _vice versâ_.