The shock was so great that, driven by some unknown but saving impulse, he threw himself forward into the water just as the soldiers fired.

He heard the four rifles roaring together.

Then he swam below water to the far edge of the pond and came up under the shelter of its circling shrubbery, raising above its surface only enough of his face for breath.
As his eyes cleared he saw the four soldiers standing at the far edge of the pond, looking at the water.

Doubtless they were waiting for his body to reappear, as his action, half fall, half spring, and the roaring of the rifles had been so close together that they seemed a blended movement.
He was trembling all over from intense nervous exertion and excitement, but his mind steadied enough for him to observe the soldiers.
Undoubtedly they were talking together, as he saw them making the gestures of men who speak, but, even had he heard them, he could not have understood their German.

They were watching for his body, and as it did not reappear they might make the circle of the pond looking for it.
He intended, in such an event, to leap out and run, but the elements were intereceding in his favor.