Introduction and books 1,2

Abū al-Hajjāj angle ABC angle BAC Apollonius appears Arabic Archimedes Aristotle assumed axioms base bisects Campanus centre circle circumference coincide commentary Common Notion congruent conics construction contained curve definition edition Elements enunciation equal equilateral Eucl Euclid Euclid of Megara Euclid's Elements Eudemus Eutocius fact figure Fihrist follows Geminus geometers geometry given straight line gives gnomon greater Heiberg Heron hypothesis ibid interior angles interpolated later Latin lemma less magnitude mathematical means meet namely Pappus parallel parallelogram passage perpendicular plane Plato porism Posidonius postulate problem Proclus produced proposition proved Pythagorean quoted rectangle rectilineal reductio ad absurdum reference regards respectively right angles says Schol scholia scholium segment sides Simplicius Simson six Books solid square suppose surface Suter Tannery Theon Theonine MSS theorem things translation treatise triangle ABC words wrote δὲ καὶ τὰ τὸ τοῦ τῶν