A sort of poisonous floating goo

Above: fog shrouds the lower fifty stories of the 1201 Third Avenue Tower in Seattle.

From a new book on fog, a snippet of 19th century London:

Because it was omnipresent and unavoidable, fog was continually written about—providing a descriptive record that evocatively delineated London fog’s “biography.” In 1853, one Londoner described it as “grey-yellow, of a deep orange.” By 1901, it had become “brown, sometimes almost black.” Corton, a scholar at Wolfson College, Cambridge, tracks the different appellations given London’s fog: In its innocent 18th-century youth, fog was described as a “mist.” By the mid-19th century its uglier character had emerged under the guise of a “pea-souper,” since that’s what its color resembled. Visiting London in 1849, Herman Melville wrote in his journal of “the oldfashioned pea soup London fog—of a gamboge [orange-yellow] color.” Newspaper accounts also described how the city’s population was “periodically submerged in a fog of the consistency of pea-soup.”