When the hissing died he was surrounded by yellow fog.
It was now fully dark, and a yellow fog was rising.
The path lit up like a strip of glowing yellow fog under his feet.
For a few seconds I couldn't see anything but that yellow fog swirling all around.
Once again they settled down to rest in the enervating yellow fog.
The river mist had become a thick yellow fog.
The yellow fog that rubs its back upon the window-panes.
A yellow fog seemed to cover the ground ahead.
They threw jars that burst into yellow fog on impact.
Their feet were splashing through some kind of marsh, in the yellow fog.