Note 11 — Introductory material
Reading edition
The Astrolabe.—For descriptions of astrolabes used by the Arabs, see pp. 338–357 of “Matériaux ... Sciences Mathém.,” by L. A. Sedillot, Paris, 1845, and for plates showing the construction of the compass and other nautical instruments of his time, consult Crescentio (Bartolomeo), “Nautica Mediterranea,” Rome, 1602.
The invention of the astrolabe is ascribed to Hipparchus, and Chaucer’s description in 1391 is the first book treating of it in time and importance. In Chaucer’s “Treatise on the Astrolabe,” he declares his intention of making use of the calendars of the reverend clerks John Somer and Nicholas of Lynne. His reference here is to the Minorite astronomer John Somer—Semur—Somerarius—and to the Carmelite Nicholas, who was lecturer in theology at Oxford (“Dict. of Nat. Biog.,” Vol. LIII. p. 219).
See the illustrated description of an astrolabe by S. A. Ionides, in “Geog. Journ.” for Oct. 1904, pp. 411–417, accompanying references to other works treating of astrolabes; “Le Courrier du Livre,” Quebec, 1899, Vol. III. p. 159, alluding to three works on the astrolabe of Samuel Champlin and Geoffrey Chaucer; “Canada,” by J. G. Bourinot, London, 1897, p. 79, with cut of Champlin’s lost astrolabe made in Paris during 1603; also the entry for Nicholas Bion to be found herein at A.D. 1702.