This excellent simile is nearly as good as that other, Blacker than a funeral of negroes in a thunderstorm. (Dow, Jun., 4th Series, p. 212.)
1846. All was dark as a stack of black cats.A Catfish Story, in the St. Louis Reveille, n.d.
a. 1853. You will go down, down, down, into the bottomless pit, that is darker than a stack of black cats.Dow, Jun., Patent Sermons, iii. 20.