On the promontories of this "coastline" the enemy proceeded to fortify themselves. They did the same at other points along their front and notably on the ridge across Champagne, and on the hills to the south-east of Verdun, as well as on the eastern spurs of the Vosges. Simultaneously in the trench warfare they revived grenade throwing, and the use of the trench mortar, expedients which had disappeared from military operations for 200 years. These devices were accompanied by systematic sniping. As skill with the rifle is not a strong point with the German army, a prismatic telescopic sight was invented. This reduced sniping practically to a mechanical trick. If the object fired at was centred on the prism a hit became a certainty--wind permitting. Sapping and mining were also persistently carried on, and the front became for mile after mile a monstrous network of pits, barbed-wire entanglements, electric alarm traps, and obstacles of every sort. In short, what the Germans lacked in comprehensive military skill they made up in laborious detail. If now we glance at the activity of the Allies, we find that the hardest part of their work was that of solidifying their line in order in the first place to make it invulnerable against German counter-attacks. Those counter-attacks were, as we have seen, to begin with heavy. In support of them the advantage which the enemy then had in howitzers was utilised to the full. During the first weeks of the winter campaign the Allied troops had to hold trenches for the most part hastily made in the stress of battle, and hold them both against this prodigal bombardment with heavy German shells, and through bitter conditions of wet and cold. To reach their trenches along the flooded area in Flanders men had in some places to cross stretches of country on planks, the targets in coming and going for the enemy's shrapnel. The weather, too, was sometimes so severe that the water in the men's drinking bottles turned to ice. The trenches were frozen puddles. Writing at this time the French "Eye Witness" said: From the sea to the Lys the operations to the north of the Lys have become terribly difficult. The liquid and cold mud from which the men suffered invaded the breeches of the guns, so that they could no longer fire, and they had to fight with the butt-end of their rifles and with their fists. Our soldiers, according to the expression of one of their leaders, have become blocks of mud. The attempt has been successful to provide for them when they leave the trenches a proper bath and a complete change of linen, which they appreciate very much. Their unalterable good humour enables them to endure with the best possible grace the rough life which is imposed upon them.