Eratosthenes

Eratosthenes
Born	276 BC Cyrene
Dee'd	194 BC Alexandria
Ethnicity	Greek
Thrift	Scholar Librarian Poet Inventor

Eratosthenes o Cyrene (/ɛrəˈtɒsθしーたəniːz/; Greek: Ἐρατοσθένης, IPA: [eratostʰénɛːs]; c. 276 BC – c. 195/194 BC) wis a Greek mathematician, geografer, poet, astronomer, an muisic theorist. He wis a man o learin, acomin the chief leebrarian at the Leebrar o Alexandria. He inventit the discipline o geografie, includin the terminology uised the day.

He is best kent for bein the first person tae calculate the circumference o the Yird, that he did bi comparin angles o the mid-day Sun at twa places a kent North-Sooth distance apairt. His calculation wis remerkably accurat. He wis an aw the first tae calculate the tilt o the Yird's axis, again wi remerkable accuracy. Additionally, he mey hae accuratly calculatit the distance frae the Yird tae the Sun an inventit the leap day. He creatit the first map o the warld, incorporatin parallels an meridians based on the available geografic knawledge o his era.

Eratosthenes wis the foonder o scienteefic chronology; he endeavoured tae revise the dates o the chief leeterar an poleetical events frae the conquest o Troy. Eratosthenes datit The Sack o Troy tae 1183 BC. In nummer theory, he introduced the sieve o Eratosthenes, an efficient method o identifeein prime nummers.

He wis a feegur o influence in mony fields. Accordin tae an entry in the Suda (a 10t-century reference), his creetics scorned him, cryin him Beta (the seicont letter o the Greek alphabet) acause he ayeweys cam in seicont in aw his endeavors. Nanetheless, his devotees nicknamed him Pentathlos efter the Olympians that war weel roondit competitors, for he haed pruiven himsel tae be knawledgeable in ivery aurie o learin. Eratosthenes yearned tae unnerstaund the complexities o the entire warld.