Harley MS 80, ff 85r-98r, ff 94r-97r

Jacob ben Machir ibn-Tibbon (Profatius Judaeus), Novus quadrans seu Practica novi Quadrantis; composed in 1288, corrected in 1301. The Latin version of a treatise on the canons of a new quadrant by Jacob ben Machir ibn-Tibbon (1236-1305), a Jewish scholar and astronomer of Marseilles and Montpellier, called Don Profiat Tibbon in Provençal or Profatius Judaeus in Latin. The text describes the new astrolabe-quadrant for calculating the time invented by Makir in 1288. Title 'Incipit novus quadrans compositus a Magistro profacio ebre [sic] / Anno domini 1288 et correctus ab eodem anno domini 1301', incipit: 'Cum stellarum sciencia sine instrumentis congruis', explicit: 'profunditate ostendit numeris / Explicit practica novi quadrantis'.

Another copy in Royal MS 12 C. xvii, ff. 71v-80r. For Makir, see M. Tibon-Cornillot, 'Une famille juive en Provence et Languedoc: les Tibonides', Amira. Repères occitans, 7 (1984), 34-35; Y. Georgelin, 'Marseille confluent de l'astronomie arabe juive et chrétienne', Provence Historique, 47 (1997), 613-21. For the text, see R. T. Gunther, Early Science in Oxford, 2 vols (Oxford: Oxford University Press, 1920), II, pp. 163-165. For a discussion of this Latin version of the text as an autograph revision of the translation from Hebrew into Latin made around 1290 by Armengaud Blasius (d. 1314) see L. Thorndike, 'Date of the translation by Ermengaud Blasius of the work on the quadrant by Profatius Judaeus', Isis, 26 (1936/37), 306-09.