[259] See Woepcke's description of a manuscript in the Chasles library, "Recherches sur l'histoire des sciences mathématiques chez les orientaux," Journal Asiatique, IV (5), 1859, p. 358, note.
[260] P. 56.
[261] Reinaud, Mémoire sur l'Inde, p. 399. In the fourteenth century one Sihāb al-Dīn wrote a work on which, a scholiast to the Bodleian manuscript remarks: "The science is called Algobar because the inventor had the habit of writing the figures on a tablet covered with sand." [Gerhardt, Études, p. 11, note.]
[262] Gerhardt, Entstehung etc., p. 20.
[263] H. Suter, "Das Rechenbuch des Abū Zakarījā el-Ḥaṣṣār," Bibliotheca Mathematica, Vol. II (3), p. 15.
[264] A. Devoulx, "Les chiffres arabes," Revue Africaine, Vol. XVI, pp. 455-458.
[265] Kitāb al-Fihrist, G. Flügel, Leipzig, Vol. I, 1871, and Vol. II, 1872. This work was published after Professor Flügel's death by J. Roediger and A. Mueller. The first volume contains the Arabic text and the second volume contains critical notes upon it.
[266] Like those of line 5 in the illustration on page [69].
[267] Woepcke, Recherches sur l'histoire des sciences mathématiques chez les orientaux, loc. cit.; Propagation, p. 57.
[268] Al-Ḥaṣṣār's forms, Suter, Bibliotheca Mathematica, Vol. II (3), p. 15.