this statement with a somewhat lengthy reference to the constellation Ophiuchus, or the Serpent, in explanation of the method of description. After having the surface of the globe portioned out for the representation of the several constellations and the important circles, he then proceeds, as he states, to consider the execution, by which he means representing in proper color and outline the several figures, and the mounting of the globe. Upon a properly constructed support should first be placed the horizon circle, through which a second circle should be made to pass; this second circle will serve as a meridian. These circles, he observes, will enclose the ball, all the points of the surface of which should be equally distant from the inner surface of the horizon and meridian circles, that is, there should be a perfect adjustment of the enclosing rings and the enclosed ball. The surface of the sphere should be painted a dark color, as, for example, azure. He sets forth, with considerable detail, the proper method of procedure in locating the several principal circles, each of which should be graduated. The zodiac should be divided into twelve parts, and the constellations belonging to each of the several parts should be designated by name, beginning with Cancer, following this with Leo, Virgo, and so on, one after the other. In giving the globe a position which actually conforms to the world, the pole should be set to the north, and the movement of the sky can then be imitated by turning the globe to the left. Leontius, by way of summary and definition, at the conclusion of his treatise, speaks of a sphere as a solid having a surface, from all the points of which, if straight perpendicular lines of equal length be drawn, they will reach a point within called the center. This center in the great sphere of the universe is the earth. The poles of the sphere are the extremities of the axis on which it turns. The horizon cuts the sphere into two hemispheres, the one superior and the other inferior to the earth. The sky, which is continually turning, encircles all, one half of it being above, the other below the earth, which is as far removed from the superior part of the heavens as from the inferior.48
NOTES
30 Cicero’s allusion to Thales, cited p. 16, is probably a reference to a tradition.
31 Wolf, R. Geschichte der Astronomie. München, 1877, p. 193; Gassendi, P. Opera Omnia. Leipzig, 1658. Vol. V, p. 375. See statement by Cicero, cited below, p. 17.
32 Aratus’ poem bore the title, “Phaenomena.” See, for an excellent edition of this poem, Prince, C. L. Phenomena. A literal translation of the astronomy and meteorology of Aratus. Lewes, 1895. In his “Bibliographical remarks,” the translator refers to one hundred and nineteen editions of this poem, dating from the first printed at Bonn in the year 1474. See also n. 48, below.
33 Passeri, G. B. Atlas Farnesianus Marmoreus insigne vetustatis monumentum. (In: Gori, A. F. Thesaurus gemmarum antiquarum astriferarum. Firenze, 1750. Vol. III.); Denza, P. F. Globi celesti della Specola Vaticana. (In: Publicazioni della Specola Vaticana. Torino, 1894. pp. xx-xxiii.)
34 Cicero. De Republica. Bk. I, chap. xiv. The citation is from the translation by Hardingham, G. G. The Republic. London, 1884.
35 Lactantius. Institutiones divinae. Bk. II, chap. v.
36 Pappus. Collectionum mathematicarum. Edited by Commandino. Urbino, 1588. Bk. VII. See especially the introduction.
37 Hultsch, F. Uber den Himmelsglobus des Archimedes. (In: Zeitschrift für Mathematik und Physik. Leipzig, 1878. Bd. 22. Hist. Litt. Abteilung, p. 106.); Same author. “Archimedes.” (In: Real-encyklopädie der klassischen Alterthumswissenschaft.)
38 Wolf, op. cit., pp. 122–124.
39 Wolf, op. cit., pp. 160–166.
40 Wolf, op. cit., p. 130.
41 Ptolemy, C. Syntaxis. (Almagest.) Various editions. Bk. VII, chap. 1. This work was first printed in Venice, 1496; the first Greek text in Basel, 1538. See Hues, Tractatus de Globis, for an analysis of this work.
42 Pliny. Historia Naturalis.
43 Ptolemy, op. cit., Bk. V, chap. i; Bk. VII, chap. v; Bk. VIII, chap. iii. Ptolemy mentions by name forty-eight constellations, all of which he probably obtained from the earlier Greeks. These constellations, the names being still retained, are: The Zodiac.
| Aries | Cancer | Libra | Capricornus |
| Taurus | Leo | Scorpio | Aquarius |
| Gemini | Virgo | Sagittarius | Pisces |
The Northern Hemisphere.
| Andromeda | Corona | Lyra | Ursa Major |
| Aquila | Cygnus | Ophiuchus | Ursa Minor |
| Auriga | Delphinus | Pegasus | Sagitta |
| Boötes | Draco | Perseus | |
| Cassiopeia | Equuleus | Serpens | |
| Cepheus | Hercules | Triangulum |
The Southern Constellations.
| Ara | Cetus | Crater | Lupus |
| Argo Navis | Centaurus | Eridanus | Orion |
| Canis Major | Corona Australis | Hydra | Piscis Australis |
| Canis Minor |
Corvus
|
