At the turn toward the 19th century, Helen Maria Williams established her reputation as a writer of ＂radical sensibility.＂ The Letters from France series chronicles her witness of the French Revolution, whereas A Tour in Switzerland, composed during the Reign of Terror, records her exile in the Alpine republic. In the text of A Tour in Switzerland, her observation moves along the double axis of landscape and politics, and in its appendix she reveals the geological foundation of her political conviction. This double structure has yet to receive nuanced critical readings. The text and the appendix form an organic composite structure, with the part corresponding to the whole in a robust relationship. Like her role of a salonnière, she sometimes introduces, and sometimes translates, various opinions from different parties. This essay reads A Tour in Switzerland against the parallelism between civil and natural history, with a view to investigating how at the Swiss Alps-the ＂theatre of life＂-Williams expounds through geo-aesthetics her conviction in the geological theory of ＂dynamic equilibrium＂ in order to maintain her optimism in human affairs during the revolutionary upheaval.