Deleuze on Francis Bacon's Head VI (1949)
"There are other techniques of isolation: putting the Figure inside a cube, or rather, inside a parallelpiped of glass or ice [. . .] The important point is that [this technique] do[es] not consign the Figure to immobility but, on the contrary, render[s] sensible a kind of progression, an exploration of the Figure within the place, or upon itself. It is an operative field" (Deleuze Francis Bacon: The Logic of Sensation 5-6).
"And the scream, Bacon's scream, is the operation through which the entire body escapes through the mouth" (Deleuze FB 16).