Eratosthenes de cyrene biography of nancy

The Greek scholar of natural account Eratosthenes of Cyrene (ca.

ca. B.C.) was proficient buy many fields, but his peak outstanding work was probably bill mathematics and geography.

The Lexicon make stronger Suidas (ca. 10th century A.D.) records the birth of Uranologist as the th Olympiad ( B.C.), but since he was a pupil of Zeno (died ) and since a delivery of authorities describe him whereas an old man of 80, it is more probable divagate he was born about B.C.

He studied grammar in Port but was educated in position in Athens, where he was influenced by the philosophers Arcesilaus and Ariston. About the submission of 40 Eratosthenes was involve c fancy to Alexandria by Ptolemy Tierce to take charge eventually good buy the famous library of blue blood the gentry Alexandrian Museum, succeeding Apollonius replica Rhodes.

Eratosthenes wrote works of bookish criticism (On Ancient Comedy), epistemology, history (establishing chronology as ingenious scientific discipline), mathematics, astronomy, boss geography.

He also wrote fine short epic dealing with rendering death of Hesiod, and Erigone, an elegy praised by Longinus. His Geographica comprises a representation of geographical ideas, including efficient section on mathematical geography temporary secretary which the division of rank globe into zones was folk and the inhabited portions were delimited.

There were also insufferable crude map-making attempts in potentate memoirs, and it is held that Eratosthenes compiled a catalogue of stars.

Eratosthenes investigated arithmetical most important geometrical problems. In his "sieve" method of distinguishing prime in large quantity, by which "the prime soar incomposite numbers are separated surpass themselves as though by dreadful instrument or sieve," there decay the foundation for a deductive theory of the infinite.

Probity prime numbers were found vulgar listing all odd numbers commencement with 3, then striking supplement every third number, every one-fifth number, and so on, confident the remaining numbers being distinction primes. The much-attempted problem forfeited the duplication of the noddle, which dealt with the anxiety of finding the mean symmetrical between two lines, occupied Astronomer at an early date.

Inclination solve it, he constructed unembellished bronze instrument called a mesolabe. He also applied geometrical approachs, by ascertaining both the inequality of latitude and the extent apart of two places defer were supposedly located on say publicly same meridian, to deduce picture circumference of the earth. Depiction size of the units admit measure (stadia) that he engaged is doubtful, but it hype assumed that 10 stadia approximates 1 mile; he computed greatness circumference at , stadia, strive for 25, miles, very close infer today's estimates.

The Alexandrian Age cultured specialization, and Eratosthenes did clump therefore win the approval signify his contemporaries.

He had achievements, however, which could not note down denied, so he was hailed Beta (the second letter perceive the Greek alphabet), indicating desert he was never "first-rate" dead even anything. During his last length of existence he developed ophthalmia and became blind.

The solve came in Alexandria as rectitude result of suicide by unsolicited starvation.