The nought was only a point which they added to their figures, to make them ten times more; it was necessary that this point should be made very distinctly, to which end they formed it like a circle, and filled it up; this method we have neglected.
Theophanus, the Eastern chronologist, says in express terms, that the Arabians had retained the Grecian numbers, not having sufficient characters in their own language to mark them.
Menage says, they were first employed in Europe in 1240, in the Alphonsian Tables, made under the direction of Alphonso, son to king Ferdinand of Castile, by Isaac Hazan, a Jew of Toledo, and Abel Ragel, an Arabian. Dr. Wallis conceives they were generally used in England about the year 1130.
In the indexes of some old French books these figures are called Arabic ciphers, to distinguish them from Roman numerals.
NUMBER X, 10.
It is observed by Huet as a remarkable circumstance, that for calculation and numerical increase the number 10 is always used, and that decimal progression is preferred to every other. The cause of this preference arises from the number of our fingers, upon which men accustom themselves to reckon from their infancy. First, they count the units on their fingers, and when the units exceed that number, they have recourse to another ten. If the number of tens increase, they still reckon on their fingers; and if they surpass that number, they then commence a different species of calculation by the same agents; as thus—reckoning each finger for tens, then for hundreds, thousands, &c.
From this mode of reckoning by the fingers then, we have been led to prefer the number ten, though it is not so convenient and useful a number as twelve. Ten can only be divided by two and five, but twelve can be divided by two, three, four, and six.
The Roman numbers are adduced in proof of the origin of reckoning by the number ten, viz.—
The units are marked by the letter I, which represent a finger.
The number five is marked by the letter V, which represents the first and last finger of a hand.