Euclid's Elements Euclid's Elements The Elements ( "Stoicheia") is a mathematical treatise consisting of 13 books attributed to the ancient Greek mathematician Euclid in Alexandria, Ptolemaic Egypt c. 300 BC. It is a collection of definitions, postulates, propositions (theorems and constructions), and mathematical proofs of the propositions. The books cover plane and solid Euclidean geometry, elementary number theory, and incommensurable lines. "Elements" is the oldest extant large-scale deductive treatment of mathematics. It has proven instrumental in the development of logic and modern science, and its logical rigor was not surpassed until the 19th century. Euclid's "Elements" has been referred to as the
Tomb of Alexander the Great 4th or early 3rd century BC Alexander's body was transferred from the Memphis tomb to Alexandria for reburial (by Ptolemy Philadelphus in , according to Pausanias). Later Ptolemy Philopator placed Alexander's body in Alexandria's communal mausoleum. The mausoleum was called the Soma or Sema, which means "body" in Greek. By 274 BC Alexander was already entombed in Alexandria. The Tomb of Alexander became the focal point for the Ptolemaic cult of Alexander the Great. In 48 BC Alexander's tomb was visited by Caesar. To finance her war against Octavian, Cleopatra took gold from the tomb. Shortly after the death of