Raymond of Marseilles

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RAYMOND OF MARSEILLES

(fl. France, first half of twelfth century)

astronomy.

Nothing is known of Raymond’s life except that he wrote in Marseilles before and in 1141. His name appears on only one manuscript and, since Duhem was not acquainted with it, the first analysis of his work refers to him simply as an anonymous “astronomer of Marseilles.” Raymond wrote three works, which contain references to each other, either because he had already written them or because he planned to do so.

The treatise on the astrolabe, “Vite presentis indutias silentio …,” is preserved in only one manuscript (Paris, lat. 10266), which is unsigned. This treatise, which includes a section on construction and a section on use, belongs to a series of translations and original writings that between 1140 and 1150 afforded the Latin West the definitive mastery of the astrolabe. Earlier texts on this instrument date from the end of the tenth century and from the eleventh century, but they had not been able to assure such mastery due to their lack of scientific accuracy. From the technical point of view, the instrument described by Raymond is the astrolabe that became standard in university instruction from the thirteenth to the sixteenth centuries, even though he graduated the zodiac of the rete incorrectly by joining the center of the instrument to equal divisions of the equator. The astronomical data are borrowed from al-Zarqālī, whose figures Raymond preferred to those of Ptolemy: an obliquity of the ecliptic of 23°33′30″ and apsis of the sun at 17°50′ of Gemini. Raymond presented two star tables side by side. One is of twenty-seven stars, the ecliptic coordinates of which he affirmed; he attributed this table to Ptolemy but in fact it comes from the treatises on the astrolabe of Llobet of Barcelona and of Hermann the Lame.1 The other is of forty stars in ecliptic coordinates secundum sententiam modernorum, which is the slightly incorrect transcription of al-Zarqālī’s table.2 Raymond demonstrated a sincere enthusiasm for astronomy and for al-Zarqālī he had an opportunity to strengthen it a little later while writing his work on planetary movements.

This work, “Ad honorem et laudem nominis Dei…,” dates from 1141 and contains three sections: a long introduction, canons of astronomical tables, and the tables themselves. The introduction, well known through the analyses of Duhem and R. Lemay, presents a cautious but sincere defense of astronomy and astrology that attests to some knowledge of the texts of Abü Ma‘shar and of al-Zarqālī. The astronomical tables and their canons are an adaptation, for the Christian calendar and the latitude of Marseilles, of al-Zarqālī’s tables. They entailed a remarkable effort to endow astronomy with a tool for calculating the planetary positions for every date. The only similar enterprise in the Latin West had been the translation by Adelard of Baih of al-Khwārizmī’s tables.3 The calculation of the planetary longitudes in al-Khwārizmī’s work, however, is based on an approximation that transfers to the mean center a part of the correction that was later termed the equatio argumenti secundo examinata. This resulted in the presence of a coordinate, which Adelard translated by the word sublimatio, which depends on the apsis and the equation of the argument.4

Despite the facility that the use of the suhlimatio brought to the determination of planetary positions, the Latin Middle Ages did not employ this method of calculation but retained that originating with Ptolemy and developed by al-Zarqali for the Toledan Tables and by the authors of the Alphonsine Tables. The latter method consisted in correcting the equation of the argument by means of the proportional part. Raymond’s application of al-Zarqālī’s tables to the latitude of Marseilles, nearly thirty years before Gerard of Cremona’s translation of the Toledan Tables and before that of the Almagest, thus appears to have given Latin astronomers one of the first contacts with what would be, for four centuries, the standard method for determining the positions of the planets.5 It is still not known, however, how Raymond gained access to al-Zarqālī’s work; nor do we know which were the tables the mediocrity of which he and two other astronomers of Marseilles confirmed in November 1140.6

In both the work on the astrolabe and that on the courses of the planets, Raymond mentioned his intention of writing a Liber judiciorum. This text appeared to be lost; but it has recently been identified with “A philosophis astronomiam sic difinitam …,” a treatise on astrology formerly listed, on the strength of information furnished by one of its manuscripts, under the name of John of Seville.

It should be noted that a fourteenth-century manuscript from Cusa attributes to a certain “Ramundus civis Masiliensis” the translation of a treatise on alchemy, Theorica occultorum,7 but it is difficult to link it to the work of Raymond of Marseilles.

NOTES

1. These tables were published by P. Kunitzsch, Typen von Sternvcrzeichnissen in astronomischen Handschriften des 10. bis 14. Jahrhunderts (Wiesbaden, 1966), 23–30. On the nature of their coordinates, see E. Poulle, “Peut-on dater les astrolabes medievaux?” in Revue d’histoire des sciences …, 9 (1956), 301–322, esp. 316–320.

2. Published by Kunitzsch in op.cit., 73–82.

3. A. Bjornbo, R. Besthorn, and H. Sutcr, eds.. Die astronomischen Tafeln des Muhammed ibn Afasd al-Khwarizmi... (Copenhagen, 1914), K. Danske Videnskabernes Selskabs Skrifter, 7th ser., Hist.-phil. sec.. Ill, no. 1.

4. O. Neugebauer, The Astronomical Tables of al-Khwarizmi… (Copenhagen, 1962), K. Danske Videnskabernes Selskabs Skrirten, Hist.-fil. Skrifter, IV, no. 2, 23–29.

5. The canons of the Toledan Tables apparently exist in two versions, one by Gerard of Cremona and one of unknown origin and date. See J. M. Millás Vallicrosa, Estudios sobre Azarquiel (Madrid-Granada, 1943–1950), 36; and F. J. Carmody, Arabic Astronomical and Astrological Sciences in Latin Translation (Berkeley, 1956), 157–161; comparative study and criticism of the two versions remain to be done.

6. The discussion of 1140 is among the passages translated by Duhem (see bibliography), who incorrectly dates it 1139, but he corrects almost all the figures given, which he misread and did not understand.

7. L. Thorndike, A History of Magic and Experimental Science, IV (New York, 1934), 17–18.

BIBLIOGRAPHY

I. Original Works. “Le traité d’astrolabe de Raymond de Marseille,” E. Poulle, ed., is in Studi medievali, 3rd ser., 5 (1964), 866–909. M.-T. d’Alverny and E. Poulle are preparing an ed, that will contain the work on the movements of the planets, based on the three MSS known—Cambridge, Fitzwilliam Museum, McClean 165, fols. 44–47 and 51–66v (incomplete); Oxford, Corpus Christi College 243, fols, 53–62, without the tables; and Bibliothéque Nationals Paris, lat. 14704, fols. 110-135v— and the Liber judiciorunu of which about ten MSS are available.

II. Secondary Literature. See P. Duhem, Le systeme da monde , 111 (Paris, 1915), 201–216; C H. Haskins, Studies in the History of Mediaeval Science (Cambridge, 1924), 96–98; and R. Lemay, Abü Ma‘shar and Latin Aristotelianism in the Twelfth Century (Beirut, 1962), 141–157.

Three articles by E. Chabanier, who is interested only in the list of geographic longitudes included in Raymond’s tables, are inaccurate and present risky conclusions: “Uncosmographe du douzième Siècle capable de mesures exactes de longitude,” in Acadèmie des inscriptions et belles-lettres, comptes rendus des sèances (1932), 344–352; “La gèographie mathèmatique dans les manuscrits de Ptolémée,” in Bulletin de la Section de géographie du Comité des travaux historiques et scientifiques, 49 (1934), 6–7; and “La filiation de la table de Raymond de Marseille et les tables dites ptoléméennes du moyen âge,” in Comptes rendus du 15° Congrès international de géographie, Amsterdam, 1938, II (Amsterdam, 1939), 101–117.

Emmanuel Poulle

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