gether with tlie.ufeof the Numeral Figures, and oth^r 
Parts of M<^^/??m-j?^2V^/ Learning, and particularly the-/^- 
Jtronomical,) before Diophantus feems to have been known 
amongft us: And from thofe we have the name ofc 
Algebra. 
And indeed moft of the Greek^ Learning came to us the 
fame way ; the firft Tranflations of £2^^:/^'/^, Ptolemy^ and . 
others, i^ito Latin, being from the Arabic]^ Copies, and 
not from the Gr^^^ Originals. 
The ufeof the Numeral Figures (which we now have, 
but the Gr^^^^j* had not J was a great advantage to the ^ 
improvement of Algebra. 
Thefe Figures (eem to have come in ufe, in thefe Parts, 
about the Eleventh Century {ot rather in the Tenth 
Century, about the middle of it, if not fooner ; ) though 
fome others thirfk , not 'till about the middle of the 
Thirteenth j and it feems they did fcarce come to be of 
eommon ufe 'till about that time. 
Archimedes (inhh Arenarius) had laid a good Founda- 
tion of fuch a way of Computation, (as he hath indeed, 
there and elfewhere, of mofl of thofe new Improvements, 
which later Ages have advanced,-) Though he kasnot 
fitted a Notation thereunto. 
The iS^Ar^^^/w^/ Fractions (introduced, as it feems, by 
Ptolemy) did but imperfectly fupply the want of fuch a 
Method of Numeral Figures^. 
The ufe of thele Numeral Figures hath received two 
great Improvements. The one is that of Decimal Parts,, 
which feems to have been introduced (filently and unob- 
lerved) by T^giomontanus, in his Trigonometrical Ca« 
Hons, about the Year 14x0; but much advanced in the Jaft 
' and "^x^kntQQntmY.hf Simon Stevin,2iVid.Mi^. Brings, 
And this is much to be preferred before Ptolemy s Sexa- 
gefimal way, as isfliewed by the comparative ufe of both. 
And therefore Briggs , Gellibrand, and others, have at- 
tempted the introducing of this, even ia thofe cafes 
where . 
