Eustratios of Nicaea on thunder and lightning

Scholarship has attributed to Eustratios of Nicaea (c. 1050-c. 1120) a treatise on thunder and lightning, which discussed other cosmological, geographical and meteorological matters as well. The text was edited by Paola Polesso-Schiavon in 1965-1966, on the basis of two manuscripts (Parisinus gr. 1612 and Marcianus gr. III-4). Two other manuscripts (Laurentianus Mediceus Plut. VII.35 and British Library Add. 34060) show that the bishop was the author of the section on thunder and lightning only. Whereas Eustratios focused on these phenomena exclusively, his explanations were considerably more thorough than suggested in the original edition. The resulting text, written at the request of a patron, probably Maria of Alania, is strongly grounded in the Aristotelian tradition and didactic. Aristotle's meteorological theory behind thunder and lightning is explained simply, and illustrated with many examples, some of them also borrowed from John Lydos' Liber de ostensis. Beside a discussion of the authorship and the manuscript tradition, a commentary and an edition of the text are provided.