Al-Abbās ibn Said al-Jawharī
Al-ʿAbbās ibn Saʿid al-Jawharī was a geometer who worked at the House of Wisdom in Baghdad and for in a short time in Damascus where he made astronomical observations. He was probably of Iranian origin. His most important work was his Commentary on Euclid's Elements which contained nearly 50 additional propositions and an attempted proof of the parallel postulate.
