Published online by Cambridge University Press: 14 March 2012
At the beginning of the seventeenth century the great astronomer Kepler wrote to his patron, the Habsburg emperor Rudolf II:
Most noble lord, I have now for several weeks on end devoted my utmost efforts to the nativity of Caesar Augustus, about which your kingly majesty wishes to know, but, as I see, it has been almost in vain. For although it is no specially difficult task to calculate the configuration of the heavens for a particular time, nevertheless, what is lacking in the nativity we are now considering is that we no longer today know the correct time of it.
The unfortunate astronomer had spent considerable time combing the evidence of the ancient authors available to him about the date of Augustus' birth. He attempted to sift through the conflicting evidence about which day would have been Augustus' birthday, before performing complex calculations of the planetary movements, in order to assess the role Capricorn might have played in his horoscope. His ingenious solution to the problem failed to impress Rudolf, as we can see from Kepler's second letter on the subject (the emperor's letters are not extant):
Most noble lord, your kingly majesty has suspected me of a lack of diligence, as though I had not sufficiently reported the nativity of Augustus…
1 Kepler, J., Opera Omnia (ed. Frisch, , 1870), VIII, 331Google Scholar, my translation. These papers were not dated.
2 ibid., 331.
3 ibid., 333.
4 The Ascendant is the point on the zodiac rising in the East at the moment depicted by the horoscope.
5 ‘Cur autem portenderit Capricornus ipsi regnum, non reperio, nisi quod idem de nostro Rodolpho diceri potest, cui Capricornus in ortu … Sic Reginae Angliae …’ Kepler, J., Gesammelte Werke XIII (ed. Kaspar, ), 315Google Scholar.
6 Kepler had his disagreements with Scaliger: in his work De veto Anno, quo aeternus Dei Filius humanam naturam in Utero benedictae Virginis Mariae assumpsit, he argued for a different year of Christ's birth, while he kept his mind off the siege of Linz going on all around him in 1626 by inventing arguments against Scaliger's work.
7 Genethlialogy was the branch of astrology concerning birth-horoscopes.
8 Kepler, op. cit. (n. 5), 298.
9 Alberti Rubeni, Dissertatio de Natali Die Caesaris Augusti, in Graevius, I. G., Thesaurus Antiquitatum Romanarum XI (Venice, 1735)Google Scholar, col. 1378.
10 ibid., col. 1378.
11 ‘… Capricornus…hatt nichts absonderlich glückliches zu bedeiitten gehabt’, Kepler, op. cit. (n. 1), 335. Cf. Kepler, op. cit. (n. 5), 315.
12 op. cit. (n.9).
13 Suet, Aug. 94.12: ‘In secessu Apolloniae Theogenis mathematici pergulam comite Agrippa ascenderat; cum Agrippa qui prior consulebat, magna et paene incredibilia praedicerentur, reticere ipse genituram suam nec velle edere perseverabat, metu ac pudore ne minor inveniretur. Qua tamen post multas adhortationes vix et cunctanter edita, exilivit Theogenes adoravitque eum. Tantam mox fiduciam fati Augustus habuit, ut thema suum vulgaverit nummumque argenteum nota sideris Capricorni, quo natus est, percusserit’.
14 Dio Cassius LVI.25.5: .
15 Suet.,Aug. 5.1.
16 This solution was rejected by Rubens (op. cit. n. 9), col. 1379) on the grounds that another passage in Suetonius refers to Octavian's father coming late to the Senate because he had been delayed by the birth of his son, which would hardly fit with an evening nativity.
17 Kepler, Letter to Herwart, 9–10 April 1599, in op. cit. (n. 1), XIII, 320.
18 De Duobus Signis, Anthol. Lat. 43, PLM Baehrens 4, p. 144: ‘Laniger astrorum ductor Taurusque secundus, / Tum sidus geminum et Cancri fulgentis imago,/ Truxque Leo et Virgo,/ quae spicea munera gestat,/ Et Libram qui Caesar habet, Chelaeque minaces …
19 ‘Sed, cum autumnales coeperunt surgere Chelae, / felix aequato genitus sub pondere Librae. / examen sistet vitaeque necisque / imponet iugum terris legesque rogabit. / ilium urbes et regna trement nutuque regentur / unius et caeli post terras iura manebunt’.
20 ‘Hesperiam sua Libra tenet, qua condita Roma / orbis et imperium retinet discrimina reruns, / lancibus et positas gentes tollit premitque, / †qua genitus Caesarque meus nunc condidit orbem† / et propriis frenat pendentem nutibus orbem’.
21 Suet., Aug. 7.
22 Housman's edition of Book IV (1920).
23 There was a silver minting of Queen Pythodoris Philometor of Pontus with Tiberius' head on the obverse and a star between scales on the reverse which is clearly paired with an issue showing Augustus on the obverse and Capricorn on the reverse of three years earlier. W. H. Waddington, Balsdon, E. and T. Reinach, Recueil général des monnaies grecques d'Asie Mineure (1904), 1, pp. 20 and 20 bis, 21 and 21 bisGoogle Scholar. Bayet, J., R.E.L. 17 (1939), 141–71Google Scholar, suggests that the date 63 (of an unknown era) given on the Tiberius coins may correspond to A.D. 12.
24 In suppor t of Scorpio, see von Voigt, W., Philologus 58 (1899), 170–204Google Scholar, Gundel, W., RE III A 1 (1927), 605fGoogle Scholar., and T. Hölscher, ‘Historische Reliefs’, in Heilmeyer, W. D., Martin, H. G., and La Rocca, E. (eds), Kaiser Augustus und die verlorene Republik. Eine Ausstellung im Martin Gropius-Bau, Berlin, 7 Juni-14 August 1988 (1988), 351–400.Google Scholar
25 Kepler, op. cit. (n. 5), X, 109.
26 Rubens, (Dissertatio de Gemma Augustea (ed. Kähler, , 1968), 12)Google Scholar, using the reference to the Catalinarian conspiracy, argued on the other hand that it really was the Julian 23 September, which corresponded to the 18 or 19 November.
27 Scaliger, , Manilii Astronomicon (Lyons), p. 162.Google Scholar
28 Garrod, Manilii Astronomicon, Liber 11.509, pp.114–20.
29 Radke, G., Fasti Romani: Betrachtungen zur Frühgeschichte des römischen Kalendars (1990), 74–87.Google Scholar
30 Brind'Amour, P., Le calendrier romain: recherches chronologiques, Collection des Études Anciennes (1983)Google Scholar.
31 Bowersock, G., ‘The Pontificate of Augustus’, in K.A. Raaflaub and M. Toher (eds), Between Republic and Empire: Interpretations of Augustus and his Principate (1990), 380–94Google Scholar; Schutz, M., ‘Zur Sonnenuhr des Augustus auf dem Marsfeld: eine Auseinandersetzung mit E. Büchners Rekonstruktion und seiner Deutung der Ausgrabungsergebnisse, aus der Sicht eines Physikers’, Gymnasium 97 (1990), 432–57Google Scholar.
32 Scaliger counted the birth as diurnal on the grounds that it was close to sunrise, and cited the anecdote about Octavian's mother and Apollo (Suet., Aug. 49) to show that Octavian was a ten-month baby. The relevant angular relationship (aspect, in astrological parlance) was a left square. Edition of Manilius (1579).
33 A. Bouché-Leclercq, L'astrologie grecque (1899), 373. n.2.
34 Reinach, T., Num. Chron. 4.2 (1902), 3Google Scholar; Holmes, T. Rice, CQ 6 (1912), 73–81CrossRefGoogle Scholar; Bayet, J., R.E.L. 17 (1939), 141–71Google Scholar; Getty, R.J., Phoenix 5 (1951), 96–107CrossRefGoogle Scholar; Hölscher, T., Jahrbücher des Zentralmuseums Mainz 12 (1965), 71–3Google Scholar. Cf. Unger, , Neue Jahrbücher für Philologie 129 (1884), 569ffGoogle Scholar.
35 Plutarch, Romulus 12.5:
36 Abry, J.-H., R.E.L. 66 (1988), 109Google Scholar. Scaliger also changed his mind about this issue between editions of Manilius.
37 Brind'Amour, op. cit. (n. 30), 243.
38 Housman, , Manilius (1903), pp. lxx–lxxiGoogle Scholar; Housman, A. E., CQ 7 (1913), 109–14CrossRefGoogle Scholar. He began from Smyly, J.G., Hermathena 17 (1913), 136–68Google Scholar.
39 Kepler, op. cit. (n. 1), VI, 607, VIII, 332–3.
40 Rubens, op. cit. (n.9), col. 1381.
41 Riess, E., RE 11 (1896), 1822Google Scholar; Gundel, W., Philologus N.F.35 (1926), 309–38Google Scholar.
42 Cicero, De Divinatione 11.98: ‘Quidem Tarutius Firmanus, familiaris noster, in primis Chaldaicis rationibus eruditus, urbis etiam nostrae natalem diem repetebat ab its Parilibus, quibus earn a Romulo conditam accepimus, Romamque, in Iugo cumesset luna, natam esse dicebat’.
43 Kepler, op. cit. (n. 1), VI, 607.
44 Kraft, K., Jahrbuch für Numismatik und Geld geschichte 17 (1967), 18Google Scholar, n. 3. But see below on the Q. Oppius coin.
45 Hölscher, T., Jahrbuch des Zentralmuseums Mainz 12 (1965), 72Google Scholar.
46 See Barton, T. S., Power and Knowledge: Astrology, Physiognomies and Medicine under the Roman Empire (1994)Google Scholar and idem, Ancient Astrology (1994), ch. 5.
47 See the horoscope calculated for Prince Charles, in my Ancient Astrology, 210.
48 ‘O Scholion on Demophilus, in Riess, E., Nechepso-Petosiris, Philologus Suppl. VI (1892), 325–88Google Scholar, fr. 14.a.
49 Wendelin was cited in Rubens, op. cit. (n. 5), col. 1381 and, op. cit. (n. 26), 12.
50 Manilius 11.509; Gundel, W., Philologus N.F. 35 (1926), 309–38Google Scholar.
51 Rubens, op. cit. (n. 26), 12.
52 Abry, op. cit. (n. 36), simply asserts that the majority of historians have accepted the conclusions of W. Drumann and P. Groebe in Geschichte Roms (1906), 785 and of Ginzel, Handbuch des mathematischen und technischen Chronologie 11 (1911), 208, 270–3Google Scholar, supported by Holmes, T. Rice, CQ 6 (1912), 74–81CrossRefGoogle Scholar.
53 Abry, op. cit. (n. 36), 113. Thema mundi: Manilius IV.791–6, Firmicus Maternus III.1.
54 Fossing, P. S., Catalogue of the Engraved Gems and Cameos in the Thorvaldsen Museum (1929), No. 1197.Google Scholar
55 ibid., No. 1596; Zwierlein-Diehl, E. (ed.), Die antiken Gemmen des Kunsthistorischen Museums in Wien II (1979)Google Scholar, No.811.
56 Catalogue, Chiesa, G. Sena, Gemme del Museo di Aquileia (1966), No. 1502.Google Scholar
57 Pliny, HN XXXVI.69; Bowersock, op. cit. (n. 31), 384–5
58 Censorinus, De Die Natali 11.8; Varro ap. Aulus Gellius 11.10.8.
59 It was only after the Council of Nicaea, and in the Gregorian attempt to reconstruct that calendar, that the equinox fell on 23 September, or 22 September in leap years. Schutz, op. cit. (n. 31), 446–7.
60 De Re Rustica 1.28.1, see Brind'Amour, op. cit. (n. 30), 15ff.
61 See those in O. Neugebauer and H. B. Van Hoesen, Greek Horoscopes (1959).
62 ibid., 4.
63 Censorinus, De Die Natali 11.11. See also Vettius Valens 1.23.
64 In 8 B.C. a decree of Augustus, engraved on a bronze tablet, ordered the suspension of leap years for twelve years to remove the discrepancy: Brind' Amour, op. cit. (n. 30), 11.
65 CIL XII. 329f.; Aulus Gellius XV.7.3. Suet., Aug. 5.1; Dio Cassius LVI.30.5.
66 Ad fam. XIII.42.2 and VII.5.3.
67 Plutarch, Life of Romulus 12:
68 Pliny, HN XXXVI.72: ‘Ei (obelisco) qui est in campo divus Augustus addidit mirabilem usum ad deprendendas solis umbras dierumque ac noctium ita magnitudines, strato lapide ad longitudinem obelisci, cui par fierct umbra brumae confectae die sexta hora paulatimque per regulas, quae sunt ex aere inclusae, singulis diebus decre sceret ac rursus augesceret, digna cognotu res, ingenio Facundi Novi mathematici. Is apici auratam pilam addidit, cuius vertice umbra colligeretur in se ipsam, alias enormiter iaculante apice, ratione, ut ferunt, a capite hominis intellecta.’
69 Buchner, E., Die Sonnenuhr des Augustus, Nachdruck aus RM 1976 und 1980 und Nachtrag über die Ausgrabung 1980/81 (1982)Google Scholar. Globe: E. Buchner, ‘Die Kugel der Sonnenuhr des Augustus, Kat. 110’, in Heil mayer et al., op. cit. (n. 24), 244–5.
70 Bandini, A. M., De Obelisco Caesaris Augusti e Campí Marti ruderibus nuper eruto (1750).Google Scholar
71 Buchner, op. cit. (n.69), 8.
72 Pliny, HN XXXVI.70.
73 ILS 91: ‘Imp. Caesar divi f. Augustus/Pontifex Maximus…Aegypto in potestatem populi Romani redacta/soli donum dedit.’
74 E, Buchner, in Heilmeyer et al., op. cit. (n. 24), 244.
75 Pliny,HN XXXVI.73.
76 Buchner's version was still accepted by W. Gundel, Zodiakos. Tierkreisbilder im Altertum. Kosmische Bezüge und Jenseitsvorstellungen im antiken Alltagsleben (1992), 149–50.
77 Schutz, op. cit. (n. 31).
78 ibid., 455–7.
79 ibid., 455.
80 ibid., Abb. 5.
81 Hübner, W., Trierer Zeitschrift 46 (1983), 335Google Scholar.
82 Pliny, HN XXXVI.72.
83 Wallace-Hadrill, A., ‘Time for Augustus: Ovid, Augustus and the Fasti’, in Whitley, M., Whitley, M. and Hardie, P. (eds), Homo Viator: Classical Essays for John Bramble (1987), 221–30.Google Scholar
84 Hölscher, T., Jahrbuch des Zentralmuseums Mainz 12 (1965), 62Google Scholar; cf. Rubens, op. cit. (n. 26), 24: it was then that he received the name of Augustus and other honours.
85 Dio Cassius LI.19.1.
86 Plut. Ant. 33.2.
87 Kraft, K., Jahrbuch für Numismatik und Geld geschichte 17 (1967), 20–1Google Scholar.
88 See Appendix.
89 Horace, Odes 11.17.17–20; cf. Propertius IV.1.85f.
90 Dwyer, E. J., ‘Augustus and the Capricorn’, Röm. Mitt. 80 (1973), 59–67Google Scholar. Text of Nigidius [Swoboda, 122–5], 66–7.
91 Dwyer, op.cit. (n.90) 62.
92 op. cit. (n.5), XIII, 315.
93 e.g., Capricorn within the corona civica, BMC 1, 29, No. 57ff.; 60, No. 66f.; 158, No. 289 n. Kähler, RE VIIA, 419, suspects the presence of Capricorns in the pediment of a Tiberian triumphal arch in Orange.
94 BMC 1, 300, No.44ff.; perhaps also BMC 1, 56.
95 BMC III, 12, No. 78.
96 BMC V, 78, No. 340, P1.13, No. 15.
97 Vespasian, BMC 11, 32, No. 171; 45, No. 251ff.; 57, No. 332; 58, No. 340; 245f., No. 128f. Domitian, BMC 11, 59, No. 347. Titus, BMC 11, 226, No. 21; 229, No. 84.
98 BMC III, 294, No. 440. Cf. Antoninus Pius BMC IV, 224.
99 A dichotomy neatly deconstructed by Hadrill, A. Wallace, JRS 76 (1986), 66ffGoogle Scholar.
100 It appears once on denarii of L. Papius, BMCR 1, PP. 374. 3014.
101 For more detailed discussion of the inter-relations between the imperial system and astrology, see Barton, op. cit. (n. 46), Power and Knowledge.
102 Kraft, op. cit. (n. 87), 21, on RRC no. 550/2a–d. Kraft follows Alföldi, A., ‘Commandants de la flotte romaine à Cyrène’, in Heurgin, J., Picard, G. and Seaton, W. (eds), Mélanges d'archéologie, d'epigraphie et de l'histoire offerts à J.Carcopino (1966)Google Scholar, 34, but Laf franchi, Historia 9 (1935), 42Google Scholar and M. Crawford, Coinage and Money under the Roman Republic. Italy and the Mediterranean Economy (1985), 196–7, date it to 88 B.C., while Friedländer, BB. II (1865), 147Google Scholar and M. Grant, From Imperium to Auctoritas (1946), 62, date it to 36–31 B.C.
103 RRC no. 550/2a–d.
104 Glass-paste, Vollenweider, M.-L., Die Steinschneidekunst und ihre Künstler in spätrepublikanischer und augusteischer Zeit (1966), 60.Google Scholar
105 Zwierlein-Diehl, op. cit. (n. 55), No.81, Taf. 36; C. Maderna Lauter, ‘Glyptik’, in Heilmeyer et al., op. cit. (n. 24), 466, Kat 241.
106 Vollenweider, M.-L., Die Porträtgemmen der römischen Republik (1972–4), Taf. 146, 4Google Scholar; Maderna Lauter, op. cit. (n. 105), Kat. 242.
107 Hölscher, op. cit. (n. 34), 63, n. 33; Furtwängler, A., Beschreibung der Geschnittenen Steine im Antiquarium (1896), No. 5182Google Scholar; Vollenweider, op. cit. (n. 106), Taf. 143. 23.
108 Furtwängler, op. cit. (n. 107), No. 3612.
109 Vollenweider, op. cit. (n. 104), 60–1.
110 Maderna Lauter, op. cit. (n. 105), 444.
111 BMC 1, 106, No. 650–4, pl. 16, 1–3.
112 BMC 1, 113, No. 696; 698.
113 BMC 1, 62, No. 349–50.
114 W. Trillmich, ‘Munzpropaganda’, in Heilmeyer et al., op. cit. (n. 24), Kat. 320.
115 Woodward, A. M., ‘The cistophori series and its place in the Roman coinage’, in Carson, R. A. G. and Sutherland, C. H. V. (eds), Essays in Roman Coinage presented to Harold Mattingly (1956), 152.Google Scholar
116 Kraft, op. cit (n. 87), Taf. 2.6.
117 BMC 1, 29, No. 57ft.; 60, No. 66f.; 134, No. 109ff.; 139, No. 129; 158, No. 289 n.
118 Eastern: BMC 1, 110, No.679f.; Western: ibid. 56, No. 305ff. and 62, No. 344ff.
119 BMC 1.62, No. 346f., pl. 7.3.
120 Abry, op. cit. (n. 36), 115.
121 Hölscher, op. cit. (n. 34), 59–61, pls 15, 16.
122 Hölscher, T., Klio 67 (1985), 81–102CrossRefGoogle Scholar.
123 Hommel, P., Studien zu der römischen Figurengiebeln der Kaiserzeit (1954), 63.Google Scholar
124 e.g., Vespasian, BMCII, 58, No. 340; 245, No. 128f.
125 The house probably belonged to the Poppaei Sabini, perhaps the family of Nero's wife. A. Maiuri, La Casa del Menandro e il suo tesoro di argenteria (1932), 36, incorrectly describes the paired Capricorns as hippocamps, and is followed by Boyce, G. K., ‘Corpus of the Lararia of Pompeii’, MAAR 14 (1937)Google Scholar. Unfortunately I have found no better photograph than his pl. 35. See Hommel, op.cit. (n. 123), p. 61.
126 O. Elia, Pitture di Stabia (1957), 40, pl. 14. Most of the wall-painting is Flavian.
127 Bologna: Lehmann-Hartleben, K., ‘Ein Altar in Bologna’, Röm. Mitt. 42 (1927), 163–76Google Scholar pl. 21. centre; Rome: ibid., pl. 20.
128 von Mercklin, E., Antike Figurenkapitelle (1962), 25, no. 616CrossRefGoogle Scholar, cf. Fuhrmann, H., Archäologischer Anzeiger 56 (1941), 609Google Scholar, pl. 118; 612f. E. Espérandieu, Recueil général des bas-reliefs, statues et bustes de la Gaule romaine (1908– ), VIII, 6397 was identified as coming from the façade of a temple of the imperial cult in Cologne, but Hommel, op. cit. (n. 123), argued that it was a soldier's tomb.
129 Delattre, A. L., Musées de l'Algérie et de Tunisie 8.2 (1899–1900)Google Scholar.
130 Ritterling, H., RE 122 (1925), 1372–1829Google Scholar.
131 Ulcisia (Szentendre): F. Cumont, Recherches sur le symbolisme funeraire (1942), 229 no. 11.
132 Espérandieu, op. cit. (n. 129), 1; VII; X; XIV s.v. See especially: 747: from Narbonne (funerary?); 5584: from Sparsbach, with the infant Heracles strangling a snake; 5591: stele-fragment from the early first century; 8830: funerary stele from Maastricht. There is a variety of material from Moguntiacum, clearly related to the fact that Capricorn was the sign of Legion XXII Primigenia: 6397: statue (see above); 7330: stele of L. Callidius, freedman of L. Primigenius, with facing Capricorns, roses above a star and garland; 7354/7364: large monument in five fragments with Capricorns and cornucopiae combined (with globe?); 7367 with the bull of Legion VIII 8517 with cornucopia and medallion, probably with the image of Nero; 8518 with triumphant Mars(?). Hommel, op. cit. (n. 123), 62, lists further examples.
133 Budapest : Kähler, H., Die römischen Kapitelle des Rheingebietes (1939), 30, n. 1Google Scholar; Piedmonte: Cumont, op.cit. (n. 131), 161, n. 1.
134 Eichler, F.Kris, E., Die Kameen im Kunsthistorischen Museum (1927), 50–1, pl. 7Google Scholar; Maderna Lauter, op. cit. (n. 105), 453, dates it to the late Augustan period.
135 Richter, G. M. A., Catalogue of Engraved Gems of the Classical Style (1920), No. 649.Google Scholar
136 Eichler and Kris, op. cit. (n. 134), pl. 7; Hannestad, N., Roman Art and Imperial Policy (1986), No. 501.Google Scholar
137 Pollini, J., Studies in Augustan Historical Reliefs (Unpub. diss., Berkeley, 1978)Google Scholar.