Heidegger's philosophy of science is notable for the prominence it gives to visuals and visualization. This is because for Heidegger, truth - including scientific truth - is the consequence of unconcealment, the lifting of a veil. But as scientific truth is a special kind, its visualization is also special: scientific truth reveals itself to us as, in Heidegger's words, "a calculable nexus of forces." This nexus unconceals itself largely by means of instrumentation: it is this process of revelation that turns objects into objects of science. Despite its focus on visualization, however, Heidegger's philosophy of science cannot be applied directly to scientific visuals. His categories are not designed with visual exegesis in mind. For that purpose, semiotics, the science of meaning as defined by Charles Peirce, is a necessary intermediary between the abstract and the concrete, a taxonomy of icon, index, and symbol that can be employed as a set of hermeneutic probes that permit the exploration of scientific visuals as embodiments and carriers of scientific meaning. But not their sole embodiments and carriers. In achieving scientific semiosis, the verbal and visual must combine their particular strengths. This is also in accord with a Heideggerian view: science moves methodically from the visual to the propositional, though it never leaves the visual behind.