[540] The text is given in Halliwell, Rara Mathematica, London, 1839.
[541] Seven are given in Ashmole's Catalogue of Manuscripts in the Oxford Library, 1845.
[542] Maximilian Curtze, Petri Philomeni de Dacia in Algorismum Vulgarem Johannis de Sacrobosco commentarius, una cum Algorismo ipso, Copenhagen, 1897; L. C. Karpinski, "Jordanus Nemorarius and John of Halifax," American Mathematical Monthly, Vol. XVII, pp. 108-113.
[543] J. Aschbach, Geschichte der Wiener Universität im ersten Jahrhunderte ihres Bestehens, Wien, 1865, p. 93.
[544] Curtze, loc. cit., gives the text.
[545] Curtze, loc. cit., found some forty-five copies of the Algorismus in three libraries of Munich, Venice, and Erfurt (Amploniana). Examination of two manuscripts from the Plimpton collection and the Columbia library shows such marked divergence from each other and from the text published by Curtze that the conclusion seems legitimate that these were students' lecture notes. The shorthand character of the writing further confirms this view, as it shows that they were written largely for the personal use of the writers.
[546] "Quidam philosophus edidit nomine Algus, unde et Algorismus nuncupatur." [Curtze, loc. cit., p. 1.]
[547] "Sinistrorsum autera scribimus in hac arte more arabico sive iudaico, huius scientiae inventorum." [Curtze, loc. cit., p. 7.] The Plimpton manuscript omits the words "sive iudaico."
[548] "Non enim omnis numerus per quascumque figuras Indorum repraesentatur, sed tantum determinatus per determinatam, ut 4 non per 5,..." [Curtze, loc. cit., p. 25.]
[549] C. Henry, "Sur les deux plus anciens traités français d'algorisme et de géométrie," Boncompagni Bulletino, Vol. XV, p. 49; Victor Mortet, "Le plus ancien traité français d'algorisme," loc. cit.