Between the end of the 1940s and the late 1950s, a collaboration of a peculiar sort developed in Paris between the copper engraver of German origin Albert Flocon and Gaston Bachelard, the French philosopher of science and poetologist of imagination. The outcome of this encounter is not very well known even by experts of either Bachelard’s oeuvre or of post-war art in France. Flocon and Bachelard together created a series of art books to which the former contributed the engravings and the latter enriched with shorter or longer commentaries. These commentaries take the form of reflections about the hand of the engraver, the resistance that it experiences, and the constructive forces that it sets free. The encounter will be described through the presentation of a number of selected examples that will give an impression of the whole oeuvre. It also will shed light on the connection between the poetological and the epistemological interests of Bachelard.