In a memoir of his 1930s Potteries childhood, The Vanished Landscape, historian Paul Johnson describes his father taking him to see the Sytch in Burslem, an immense stretch of ground composed of clay, black water, mud, industrial detritus and ‘fumigerous furnaces belching forth fire, ashes and smoke.’
I have a fondness for words that are obscure and euphonious, but this one takes the gateau. It’s meaning is clear from the context, but it doesn’t show up in a search of the online OED. And Google returns only a handful of hits – most of them either the Paul Johnson quotation above or this one, from the same memoir:
You went down a steep track to get into Tunstall Station, a cavernous place under a bridge, of smoke-stained dingy brick, dark and fumigerous.
Searching Google Books turns up the Johnson memoir and four other books. Before that search I was beginning to suspect Johnson had invented the word; instead, I’ll give him full credit for keeping it alive.