Presently comes a whistling noise of wings, and a loud 'quack, quack!' as a string of ducks, their long necks stretched out, pass over not twenty yards high, slowly slanting downwards to the water.

This is the favourable moment for the gun, because their big bodies are well defined against the sky, and aim can be taken; but to shoot anything on the ground at night, even a rabbit, whose white tail as he hops away is fairly visible, is most difficult.
The baffling shadows and the moonbeams on the barrel, and the faint reflection from the dew or hoar-frost on the grass, prevent more than a general direction being given to the gun, even with the tiny piece of white paper which some affix to the muzzle-sight as a guide.

From a punt with a swivel gun it is different, because the game is swimming and visible as black dots on the surface, and half a pound of shot is sure to hit something.

But in the water-meadows the ducks get among the grass, and the larger water-carriers where they can swim usually have small raised banks, so that at a distance only the heads of the birds appear above them.
So that the best time to shoot a duck is just as he slopes down to settle--first, because he is distinctly visible against the sky; next, because he is within easy range; and lastly, his flight is steady.

If you attempt to have ducks driven towards you, though they may go right overhead, yet it will often be too high--for they rise at a sharp angle when frightened; and men who are excellent judges of distance when it is a hare running across the fallow, find themselves all at fault trying to shoot at any elevation.