Euclid's elements. Vol. II. [electronic resource] : Containing the seventh, eighth, ninth, tenth, thirteenth, fourteenth and fifteenth books; with the data; being the remaining parts of that work which were not publish'd by the Late Dr. Keill. Now first translated from Dr. Gregory's edition. To which is prefix'd, an account of the life and writings of Euclid. With a defence of his elements against the modern objectors. By Edmund Stone, F.R.S