Safety of the Harbour?

Morning Fog.

A thick cunning fog slinks in from the sea,
Lending the morning a ghostly chill, and,
An uncanny mixture of tranquillity and dread.
Terrifying in its silence and gentleness,
Like the harbinger of some impending catastrophe.

The tea-tray flat sea, a mirror no more,
The curious, creamy, smooth water covered
By a nebulous shroud of bleached opaqueness.
Blurring the outlines of all it encounters,
Deadening, distorting the disembodied sounds.

Beyond the shore we hear the putt, putt, putt,
Of a boat's engine as, tentatively, warily,
It gropes its way through nature's curtain,
Following the mournful wail of the fog-horn,
Trying to attain once more the safety of the harbour.