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Page 3, line 3, seqq.
In the formation of the numerals, the thousand is not, like the ten and the hundred, multiplied by the units only, but likewise by any number of a higher order, such as tens and hundreds: there being no special words in Arabic (as is the case in Sanscrit) for ten-thousand, hundred-thousand, &c.
From this passage, and another on page 10, it would appear that our author uses the word عقد, plur. عقود, knot or tie, as a general expression for all numerals of a higher order than that of the units. Baron S. de Sacy, in his Arabic Grammar, (vol. 1. § 741) when explaining the terms of Arabic grammar relative to numerals, translates عقود by næuds, and remarks: Ce sont les noms des dixaines, depuis vingt jusqu’à quatre-vingt-dix.
Page 3, line 9-11.
The forms of algebraic expression employed by Leonardo are thus reported by Cossaui (Origine, &c. dell’ Algebra, I. p. 1.): Tre considerazioni distingue Leonardo nel numero: una assoluta, o semplice, ed è quella del numero in se stesso; le altre due relative, e sono quelle di radice e di quadrato. Nominando il quadrato soggiugne QUI VIDELICET CENSUS DICITUR, ed il nome di censo è quello di cui in seguito si serve. That Leonardo seems to have chosen the expression census on account of its acceptation, which is correspondent to that of the
