 He familiarised himself with the new quantitative chemical theory of Antoine Lavosier; and read widely, including - Nicolai Tychsen's "Apothekerkunst" ("Theoretical and practical instructions for Pharmacists," 1804), Gren's "Chemistry", Adam Hauch's "Priniciples of Natural Philosophy" and Ørsted's papers in "Scandinavian Literature and Letters" (whose treatise on spontaneous combustion made an especially strong impression on him).At the same time he experimented with a home-made voltaic pile.At 17 years old, he rearranged his father's pharmacy in accordance with the new pharmacopoeia of 1805, which had imposed the antiphlogistic nomenclature.