Claude d'Iger, a student of Eugene Canselier, inherits the initiatory chain of French alchemists and Hermetic philosophers of the 20th century that goes back to Fulcanelli. The phenomenal erudition of this researcher of Hermetic science was manifested in the fact that throughout his life he collected the most frank and unambiguous statements of Adepts, mystics and esotericists of the past and present, composing from them his own original text, clarifying those omissions that so complicate the understanding of alchemical texts. The book includes alchemical treatises by Nicolas Valois, the houses of Albert Belin, Gobineau de Montlouisan and Bernard of Trevisan. The publication is equipped with reference materials and additional illustrations.