mushroom town

Let 'em quash every pocket borough to-morrow, and bring in every mushroom town in the kingdom--they'll only increase the expense of getting into Parliament.

These pit villages were places that emerged fully formed, like mushrooms, almost overnight (indeed, there is a part of Merthyr colloquially referred to, to this day, as 'Mushroom Town' for this very reason).

"Perhaps in another fifty years or more," he wrote, "this hideous mushroom town will have sunk back again into the arms of Mother Earth.