AIGNAN, FRANÇOIS. — The Capuchin missionary known as Abbé A. was in fact the Franciscan father Tranquille of Orléans (Père Tranquille), born in 1644, who transferred to the Cluniac Benedictines around 1690 and died in 1709. As a Capuchin, together with his confrere Father Enrico da Montbazon (later Abbé Rousseau), he was commissioned by King Louis XIV to direct a pharmaceutical laboratory in the Louvre Palace. To practice their art more freely, they became Benedictines; both at the Louvre and in the Abbey of Saint-Germain-des-Prés, they distributed free of charge the medicines they prepared, which were eagerly sought even by the nobility. A. became famous for the preparation of a medicinal compound still known today as the "Tranquille Balsam," composed of solanum racemosum, furiosum maniacum, poppy heads, henbane, mint, tobacco, rue, wormwood, hyssop, etc., and a large freshly killed toad. This balsam enjoyed great popularity; it was even administered to Louis XIV on the eve of his death. Madame de Sévigné considered it a sovereign remedy, useful against all ailments. The "Tranquille Balsam" has persisted to this day, though without the toad ingredient, as a local anesthetic (cf. M. Messini, Terapia clinica, 1944).
Under the name of Abbé A., he published various medical works: Le prestre médicin, ou Discours physique sur l'établissement de la médecine, avec un traité du café et du thé de France, selon le système d'Hippocrate (Paris, 1696), which includes a sketch of ecclesiastical medical history drawn from Du Val’s Historia monogramma; L’ancienne médecine à la mode, ou le sentiment uniforme d’Hippocrate et de Galien sur les acides et les alkalis (Paris, 1693); and Traité de la goutte dans l’état naturel, ou l’art de connaître les vrais principes des maladies (Paris, 1707).