Straining their medium of its opacity, I drew off the clayey liquid and replaced it with the clearer brown, wallaba-stained water of the Mazaruni; and thereafter all their doings, all their intimacies, were at my mercy.
"Edge of the Jungle"
William Beebe
If we knew on what other relations to light, or on what peculiarities of structure, opacity depends, we might find that this is only an apparent, not a real, exception to the general proposition in the text.
"A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2)"
John Stuart Mill
The eyes deep sunk in the sockets without eyebrows or eyelashes, with the pupils still beautiful, but dulled with a glassy opacity.
"The Shadow of the Cathedral"
Vicente Blasco Ibañez