From the late 1960s onwards the author embarked on a series of electron microscopic adventures using progressively more sophisticated techniques which yielded structural information and uncovered physics-chemical phenomena that would have been irretrievable by other methods. Illustrative examples include; (i) proof that photoreactivity and unexpected photoproducts of organic molecular crystals are governed by stacking faults, and that applied stress converts some photostable organic solid to photactive ones; (ii) elucidation of interdependence of photoluminesence and polymorphism in organic crystals; (iii) determination of surface pointdefect-concentration at, and discovery of catalytic channeling by metals in the oxidation of, graphite and molybdenite; (iv) establishing the mechanism of interconversion of “stages” in graphite intercalates, and the discovery of incommensurate guest-hosts-structures (with graphiteiron chloride); (v) rationalization of the structures of the many seemingly unrelated phases of bismuth molybdate catalysts (for oxidation) in terms of a common, defect-fluorite (Bi2O3) archetype;