latitude on the earth's surface, tides and basic surveying. Care must be taken not to dismiss the astrological aspects; as well as any mystical interpretation astrological terminology was used for what today would be recognized as astronomy. Determining when the sun entered a house (or sign) of the zodiac was a precise determination of the calendar. Skeat produced a number of sketches to accompany his edition: The stars listed on the rim of the rete of the drawings in the Treatise are given below with their modern names: See also The equatorie of the planetis by John Westwyk References Footnotes Citations Bibliography quoted by 5th impression. Originally published by Houghton Mifflin Co, Boston, Mass. External links Plain-text format (with line numbering): Part 1 Part 2 from eChaucer The text of A Treatise on the Astrolabe – presented in Middle English and Modern English side-by-side. A Treatise on the Astrolabe - a verb database (language analysis, description of the astrolabe and Middle English period) Medieval literature History of astronomy Astronomy books Astrological texts Works by Geoffrey Chaucer 14th-century books Treatises