The Canadian attack began at 4:25 o’clock, just as the first hint of dawn was appearing.  All night the British big guns had been pouring a steady stream of high explosive shells into the German positions, great detonations overlapping one another like the rapid crackling of machine-gun fire and swelling into a mighty volume of thunder that shook the earth and stunned the senses.  Then, a short time before the hour set for the attack arrived, the batteries ceased abruptly and a strange, almost oppressive stillness crept over the terrain which until then had been an inferno of crashing noise and death.  It had been raining and gray clouds still hung over the trenches where crouched the Canadian infantrymen, waiting eagerly for the arrival of the moment which would summon them to attack.

Suddenly, ten minutes before the time set for the advance, every British gun within range broke out with a hurricane of shelling, and solid lines of crimson lightning belched from the German trenches as the explosives broke about them.  To this lurid picture was added the spectacle of burning oil, which the British threw on the enemy lines.  Great clouds of pinkish colored smoke rolled across the country from the flaming liquid and the murky sky threw back myriad colors from the conflagration below.

The moment of attack arrived, and as the British guns dropped their protecting barrage fire in front of the Canadian trenches, the clouds parted and the yellow crescent moon appeared.  Under the light of this beacon the Canadians leaped over the parapets and began their methodical advance behind their barrage fire.

The British barrage was without a flaw, says an eyewitness.  Behind it the Canadians mounted Hill 70 and swept along the rest of the line.  On the crest of the hill, where so much blood had been, spilled before, heavy fighting might have been expected, for the position was well manned with machine guns.  The resistance here, however, was not strong, and it was not until the dwellings in the outskirts of the suburbs were reached that vigorous fighting occurred.  The ground over which the infantry advanced was honeycombed with British shell holes and the barbed wire defenses had been leveled, so that they gave little trouble.

FIGHT IN CELLARS AND DUGOUTS

The first serious resistance from the Germans was met at a point where the enemy was strongly intrenched in connecting cellars and there sanguinary fighting occurred.  The place was a sample of many other suburbs about Lens.  The city is surrounded by colliery communities which are so close together and so near the city proper that they really form part of the town.  Lens, before the war, had a population of 30,000, but had become a mass of ruins.

Following their usual tactics, the Germans had carried out systematic destruction of the houses and had constructed strong underground defenses.  The whole city was undermined with tunnels and dugouts, which had been reinforced with concrete, and most of the ruined buildings had been turned into machine-gun emplacements.