Authors:

As the gloom and shadow thickened behind him, in that place where it had been gathering so darkly, it took, by slow degrees, - or out of it there came, by some unreal, unsubstantial process - not to be traced by any human sense, - an awful likeness of himself!

Charles Dickens (2016). “Charles Dickens: The Complete Christmas Books and Stories [A Christmas Carol, The Chimes, A Christmas Tree, The Cricket on the Hearth, etc] (Book House)”, p.207, Book House
As the gloom and shadow thickened behind him, in that place where it had been gathering so darkly, it took, by slow degrees, - or out of it there came, by some unreal, unsubstantial process - not to be traced by any