De utilitatibus astrolabiiHermannus, Contractus, 1013-1054[between 1190 and 1200]latManuscript on parchment (one bifolium, one fragment) of 1) Hermannus Contractus, De utilitatibus astrolabii, text of bifolium not continuous. 2) Hermannus Contractus, Liber de mensura astrolabii, Book 1, portions of chs. 5-6. Annotated by several contemporary handsIn Latin.Script: Written in romanesque minuscule verging on gothic bookhand.Plain initials, 3- to 2-line, headings and horizontal lines for chart in orange. Diagram of dial on f. 2r; star chart on f. 3v.Bifolium used as a wrapper for a book numbered "5311".