Transmission of the Greek Classics on music ("De institutione musica libri quinque", unfinished) contributed to medieval education. "De arithmetica", begins with modular arithmetic, such as even and odd, evenly even, evenly odd, and oddly even. He then turns to unpredicted complexity by categorizing numbers and parts of numbers. His translations of Euclid on geometry and Ptolemy on astronomy, if they were completed, no longer survive. Boethius made Latin translations of Aristotle's "De interpretation" and "Categories" with commentaries. These were widely used during the Middle Ages. In the Western Provinces (what today is considered the Western Europe's heartland), the collapsing Roman empire lost many Greek manuscripts
Lighthouse of Alexandria Lighthouse of Alexandria The Lighthouse of Alexandria, sometimes called the Pharos of Alexandria (; Ancient Greek: ὁ Φάρος τῆς Ἀλεξανδρείας, contemporary Koine ), was a lighthouse built by the Ptolemaic Kingdom, during the reign Ptolemy II Philadelphus (280–247 BC) which has been estimated to be in overall height. One of the Seven Wonders of the Ancient World, for many centuries it was one of the tallest man-made structures in the world. Badly damaged by three earthquakes between AD 956 and 1323, it then became an abandoned ruin. It was the third longest surviving ancient wonder (after the Mausoleum at Halicarnassus