to subside.  The old landmarks, by whose disappearance I had measured its advance, here a crag, there a brave pine tree, now began, in the inverse order, to make their reappearance into daylight.  I judged all danger of the fog was over.  This was not Noah’s flood; it was but a morning spring, and would now drift out seaward whence it came.  So, mightily relieved, and a good deal exhilarated by the sight, I went into the house to light the fire.

I suppose it was nearly seven when I once more mounted the platform to look abroad.  The fog ocean had swelled up enormously since last I saw it; and a few hundred feet below me, in the deep gap where the Toll House stands and the road runs through into Lake County, it had already topped the slope, and was pouring over and down the other side like driving smoke.  The wind had climbed along with it; and though I was still in calm air, I could see the trees tossing below me, and their long, strident sighing mounted to me where I stood.

Half an hour later, the fog had surmounted all the ridge on the opposite side of the gap, though a shoulder of the mountain still warded it out of our canyon.  Napa valley and its bounding hills were now utterly blotted out.  The fog, sunny white in the sunshine, was pouring over into Lake County in a huge, ragged cataract, tossing treetops appearing and disappearing in the spray.  The air struck with a little chill, and set me coughing.  It smelt strong of the fog, like the smell of a washing-house, but with a shrewd tang of the sea salt.

Had it not been for two things—­the sheltering spur which answered as a dyke, and the great valley on the other side which rapidly engulfed whatever mounted—­our own little platform in the canyon must have been already buried a hundred feet in salt and poisonous air.  As it was, the interest of the scene entirely occupied our minds.  We were set just out of the wind, and but just above the fog; we could listen to the voice of the one as to music on the stage; we could plunge our eyes down into the other, as into some flowing stream from over the parapet of a bridge; thus we looked on upon a strange, impetuous, silent, shifting exhibition of the powers of nature, and saw the familiar landscape changing from moment to moment like figures in a dream.

The imagination loves to trifle with what is not.  Had this been indeed the deluge, I should have felt more strongly, but the emotion would have been similar in kind.  I played with the idea, as the child flees in delighted terror from the creations of his fancy.  The look of the thing helped me.  And when at last I began to flee up the mountain, it was indeed partly to escape from the raw air that kept me coughing, but it was also part in play.