GR translation: could not have been from fog

[Michael Bailey]

V14.25-28, P15.2-5   Carefully, black-shod step by step, Pirate approached
the thing. It began to slide forward to meet him, over the cobblestones
slow as a snail, leaving behind some slime brightness of street-wake that
could not have been from fog.

Here it's referring to the possibility of water accumulating on the
cobblestones from the fog, is that correct?




I’d say so - the usual would be fog, or “the foggy, foggy dew”

 (Old trad song, the foggy, foggy dew, Burl Ives,
https://youtu.be/tzyteR2_nOU )

Anyway, the moistened street in the wake of the Adenoid isn’t the usual
wetness.