(Ἀγαθοδαίμων), a native of Alexandria. All that is known of him is, that he was the designer of some maps to accompany Ptolemy's Geography. Copies of these maps are found appended to several MSS. of Ptolemy. One of these is at Vienna, another at Venice. At the end of each of these MSS. is the following notice: Ἐκ τῶν Κλαυδίου Πτολεμαίου Γεωγραφικῶν βιβλίων ὄκτω τὴν οἰκουμένην πᾶσαν Ἀγαθοδαίμων Ἀλεξανδρεὺς ὑπετύπωσε (Agath. of Alexandria delineated the whole inhabited world according to the eight books on Geography of Cl. Ptolemeaus). The Vienna MS. of Ptolemy is one of the most beautiful extant. The maps attached to it, 27 in number, comprising 1 general map, 10 maps of Europe, 4 of Africa, and 12 of Asia, are coloured, the water being green, the mountains red or dark yellow, and the land white. The climates, parallels, and the hours of the longest day, are marked on the East margin of the maps, and the meridians on the North and South. We have no evidence as to when Agathodaemon lived, as the only notice preserved respecting him is that quoted above. There was a grammarian of the same name, to whom some extant letters of Isidore of Pelusium are addressed. Some have thought him to be the Agathodaemon in question. Heeren, however, considers the delineator of the maps to have been a contemporary of Ptolemy, who (8.1, 2) mentions certain maps or tables (πίνακες), which agree in number and arrangement with those of Agathodaemon in the MSS.
Various errors having in the course of time crept into the copies of the maps of Agathodaemon, Nicolaus Donis, a Benedictine monk, who flourished about A. D. 1470, restored and corrected them, substituting Latin for Greek names. His maps are appended to the Ebnerian MS. of Ptolemy. They are the same in number and nearly the same in order with those of Agathodaemon. (Heeren, Commentatio de Fontibus Geograph. Ptolemaei Tabularumque iis annexarum ; Raidel, Commentatio critico-litcraria de Cl. Ptolemaei Geographia ejusque codicibus, p. 7.)[C.P.M]