FASA Games, Inc.

information on The London Fog. Given the level of accelerated industrialization in 1879, this sort of thing might be seen much earlier.

And a pleasant thought, Smog Elementals may be a thing

https://en.wikipedia.org/wiki/Pea_soup_fog

Oh, they are, they are. What kind of deviltry could be caused by a villainous priest or shaman conjuring the spirit of a London Particular?