The German position at La Bassee formed a buttress of the line which they had been striving to draw across the valley of the Lys. Their line from La Bassee across the flats of the valley as far as the hills south of Ypres had become a maze of diggings and entanglements, and was deemed to be impregnable. It was important to break this barrier. For five months at enormous cost the enemy had fought to build it up and to maintain it.
The village of Neuve Chapelle lay about half way between the spur of La Bassee on the south and the Lys on the north. The distance between the promontory on the one side and the river on the other is some eight miles. Neuve Chapelle was on the flat. From La Bassee round behind Neuve Chapelle the "inland coastline" curves, forming a bay completed near the villages of Fournes and Aubers by another promontory known as the Haut Pommeau. The distance from La Bassee to Fournes as the crow flies is five miles. Beyond Fournes again the "inland coastline" bends round sharply, and describes a much greater bay in which is situated the city of Lille. Eastward of Neuve Chapelle on the slope of the higher land is the Bois de Biez, and this with the hamlet of Pietre it was one of the British objectives to seize.
With these places in British hands the German hold on both Lille and La Bassee would be rendered precarious.
Now let us look, in its general aspects, at the British tactical plan.
A massed force of guns, including batteries of heavy howitzers, was at a given time (7.30 a.m. on the morning of March 10) to open on the German line of trenches, extending across the flat country and half-a-mile or so to the west and in front of Neuve Chapelle. Behind these trenches ran the main road from La Bassee to Armentières. For thirty-five minutes the guns were to keep up their squall of fire. By that time it was calculated the German trenches would be knocked to pieces; the entanglements and obstacles cut through; and the defending troops either killed, wounded, or demoralised. At the end of the thirty-five minutes the infantry of the First Army were to rush the position. Meanwhile, the artillery was to alter the range and sweep with a like squall of fire Neuve Chapelle and the German second line of defences to the north and south of the village. Then the infantry were to advance to this second line. In turn the artillery were now to sweep the area beyond the village, and to throw a curtain of fire along the slopes of the higher land. While this was being done the infantry were again to advance from Neuve Chapelle on to the slopes more particularly towards the Bois de Biez and Pietre, while the guns further extended their range.
It will be seen that the infantry rushes had to take place between the artillery squalls. The latter had of necessity to be regulated by a time table. It was an application on a large scale of the tactics carried out in Champagne and round Arras, Roye, and at Les Esparges.
Both the massing of the guns and that of the troops intended for this operation was carried out alike with secrecy and success. The batteries during several days preceding the battle had taken up their allotted positions without the Germans becoming aware of it. From the German lines the guns of course were out of sight. The troops had been massed in the first instance at points in the rear. From these they marched during the night before the battle to the British line of trenches. It is remarkable that the movement of these hosts remained undetected. Amid the unrelieved darkness of the ruined country they set out along the shell-pitted roads, regiment after regiment, brigade following brigade. They moved as silently as possible, as silently as only British troops can when silence is called for. At ten o'clock on the evening of March 9 this march began. Through devastated and deserted villages passed the subdued tramp of these legions, men from every part of the British Isles, regiments famous for valour on many a field.
Behind the British lines the corps halted along the roadsides. After their march they were served with hot coffee. They extended for mile after mile—Highlanders and Riflemen; Territorials and Indians; a magnificent army, and in immediate command of it one of the ablest and most resolute of British generals.
Still, apparently, the Germans suspected nothing. No outward sign of alertness was to be observed along their line. The soughing of the bleak night wind of March alone broke the silence. Then one by one the regiments moved by single files through the communication ways down into the trenches till these were filled with men. From the enemy's front there was yet no alarm, though their trenches were at many points less than 100 yards away.
Towards morning there comes out of the darkness a dull boom. A pause and then another. After a further pause a third. The guns are registering the range.