Carrying a man on a stretcher was not as easy as it might seem. Erik thought his arms would fall off when they were only halfway. But he could see that the patient was in greater pain by far, and he just kept running.

Shells no longer fell around them, he noticed gratefully. The French were concentrating all their fire on the river bank, trying to prevent the Germans crossing.

At last Erik and Hermann reached the farmhouse with their burden. Weiss had the place organized, the rooms cleared of superfluous furniture, places marked on the floor for patients, the kitchen table set up for operations. He showed Erik and Hermann where to put the wounded man. Then he sent them back for another.

The run back to the river was easier. They were unburdened and going slightly downhill. As they approached the bank Erik wondered fearfully whether he would panic again.

He saw with trepidation that the battle was going badly. There were several deflated vessels in midstream and many more bodies on the bank – and still no Germans on the far side.

Hermann said: ‘This is a catastrophe. We should have waited for our artillery!’ His voice was shrill.

Erik said: ‘Then we would have lost the advantage of surprise, and the French would have had time to bring up reinforcements. There would have been no point in that long trek through the Ardennes.’

‘Well, this isn’t working,’ said Hermann.

Deep in his heart Erik was beginning to wonder whether the Führer’s plans really were infallible. The thought undermined his resolution and threatened to throw him completely off balance. Fortunately there was no more time for reflection. They stopped beside a man with most of one leg blown off. He was about their age, twenty, with pale, freckled skin and copper-red hair. His right leg ended at mid-thigh in a ragged stump. Amazingly, he was conscious, and he stared at them as if they were angels of mercy.

Erik found the pressure point in his groin and stopped the bleeding while Hermann got out a tourniquet and applied it. Then they put him on the stretcher and began the run back.

Hermann was a loyal German, but he sometimes allowed negative feelings to get the better of him. If Erik ever had such feelings he was careful not to voice them. That way he did not lower anyone else’s morale – and he stayed out of trouble.

But he could not help thinking. It seemed the approach through the Ardennes had not given the Germans the walkover victory they had expected. The Meuse defences were light but the French were fighting back fiercely. Surely, he thought, his first experience of battle was not going to destroy his faith in his Führer? The idea made him feel panicky.

He wondered whether the German forces farther east were faring any better. The 1st Panzer and the 10th Panzer had been alongside Erik’s division, the 2nd, as they approached the border, and it must be they who were attacking upstream.