This extraordinary document was first published in 1620. It contains tables of correspondences and other materials, especially sigils, which go beyond those in Agrippa's Occult Philosophy. The engraving was executed by the brilliant Johannes Theodorus de Bry who illustrated other important occult works such as those of Robert Fludd. Adam McLean theorized and Carlos Gilley confirmed that the original manuscript on which the printed Magical Calendar was based is British Library manuscript Harley 3420. (Gilley, Carlos, "The rediscovery of the original of Großchedel's Calendarium Naturale Magicum Perpetuum," in Carlos Gilly, Cis van Heertum (ed.) Magia, Alchimia, Scienza Dal '400 al '700. L'influsso di Ermete Trismegisto Centro Di: 2 vols. Firence, 2002, vol. 1 pp. 310-317.) This edition by Adam McLean has the original Latin text and engravings, with parallel English translation. McLean also supplied an 11 page introduction and 35 pages of valuable notes and commentary explaining the diagrams and their provenance. I hope if McLean continues with a third edition he will explore the considerable influence the text had on Western occultism. At least two grimoires -- Abognazar and Janua Magicae Reserata -- depend heavily on the Magical Calendar. In my research on esoterica, I find myself constantly referring to this volume.