“I was very handsome and made the best impression on myself. We took a car (sharing the cost). Ricchetti terribly nervous, me completely serene thanks to a small dose of cocaine, although his own success is assured, and I for my part have every reason to fear ridicule. (…) Here are my performances (or rather those of cocaine) and I am very satisfied. » Freud, letter to Martha dated January 20, 1886. In the course of the 1880s, the young Freud, who had not yet surveyed the labyrinths of the Unconscious, tried to make himself known by publishing studies concerning erythroxylon coca, a plant from which an alkaloid, cocaine, is made, the properties of which he praises. We add to these studies, of which the French-speaking reader will find a new translation here, a few letters to Martha Bernays, his future wife, which shed light on Freud's intimacy with drugs.