Johnstone of the Border by Harold Bindloss

Pale moonlight trembled across the foaming sea and faded again as the _Rowan_, rolling hard, bore up for the Solway. Whitney held the helm, his lips set and his brows knitted, for with the savage wind astern the yacht was hard to steer. The small storm-jib ran water as it swung above the seas, and the black, close-reefed mainsail lurched to and fro, lifting its heavy boom high above Whitney's head, at the risk of carrying away the mast if he let it jibe across. Andrew stood in the cockpit, with the spray rattling like shot on his oilskins, his night glasses steadied on the cabin top as he searched the sea ahead. He saw enough to daunt a stranger to the firth.

The hills along the western shore were indicated by a vague blackness devoid of outline, but Andrew could distinguish a belt of broken water that stretched across his course and faded into the gloom. The backs of the seas were toward him and he noted how their crests were cut off by the wind as they curled against the tide, which was running down the firth. In some places their length and regularity indicated depth of water, but, for the most part, they boiled in frothy confusion across the shoals. A steady beam of light stretched out from the shore, but this was not much guide to the intricate channel through the sands. While he watched, the moon came out, and as its light widened, smooth, bright patches became visible amidst the turmoil. These were the tops of the banks that the tide was leaving.