It also attracted scholars from all over the Mediterranean such as Eratosthenes of Cyrene.

Cyrene was the birthplace of Eratosthenes and there are a number of philosophers associated with the city including Aristippus, the founder of the School of Cyrene, and his successor daughter Arete, Callimachus, Carneades, Ptolemais of Cyrene, and Synesius, a bishop of Ptolemais in the 4th century AD.

Using this measuring instrument Eratosthenes of Cyrene ( ca.

* Chronicle ( Χρονικά ), a Greek history in verse from the fall of Troy in the 12th century BC to roughly 143 BC ( although later it was extended as far as 109 BC ), and based on previous works by Eratosthenes of Cyrene.

* A twelve-book essay about Homer's Catalogue of Ships, also based on Eratosthenes of Cyrene and Demetrius of Scepsis, dealing with Homeric geography and how it has changed along the centuries.

Eratosthenes of Cyrene ( 276-196 BC ) deduced the circumference of the earth with remarkable accuracy.

The Earth's circumference was first determined around 240 BC by Eratosthenes.

Eratosthenes knew that in Syene, in Egypt, the Sun was directly overhead at the summer solstice, while he estimated that the angle formed by a shadow cast by the Sun at Alexandria was 1 / 50th of a circle.

Early in Classical Greece, that the earth is a sphere (" round "), was generally known by all, and around 240 BCE, Eratosthenes ( 276 BCE – 194 BCE ) accurately estimated its circumference.

A Sieve of Eratosthenes benchmark, computing all prime numbers less than 65536, was tested on a Sun SPARCstation 1.

A statement of Eratosthenes attributed by Strabo to Pytheas, that the north of the Iberian Peninsula was an easier passage to Celtica than across the Ocean, is somewhat ambiguous: apparently he knew or knew of both routes, but he does not say which he took.

Book 34 was entirely devoted to questions of geography and included some trenchant criticisms of Eratosthenes, whom he accused of passing on popular preconceptions or laodogmatika.

Although Strabo cited the antique Greek astronomers Eratosthenes and Hipparchus, acknowledging their astronomical and mathematical efforts towards geography, he claimed that a descriptive approach was more practical, such that his works were designed for statesmen who were more anthropologically than numerically concerned with the character of countries and regions.

That alternative route, different from the theoretical eastward route, was based on calculations of the Earth's circumference made by Columbus which showed the measurement to be substantially less than the classic 10, 000 mile figure given by Eratosthenes in the 3rd century BC.

The Portuguese Court, which agreed with the figure provided by Eratosthenes, rejected Columbus ' proposal because they believed that the distance to Asia over the open Western Ocean was too great for the ship's crews to survive the journey without being able to make port and resupply.

Posidonius was celebrated as a polymath throughout the Graeco-Roman world because he came near to mastering all the knowledge of his time, similar to Aristotle and Eratosthenes.

Posidonius was informed in his approach to finding the Earth's circumference by Eratosthenes, who a century earlier used the elevation of the sun at different latitudes to arrive at a figure of 250, 000 stadia ( which he rounded to 252, 000 so that it would be divisible by 60 ).

An example of the sort of attack this portrayal was intended to defend against can be found in two orations of Lysias, Against Eratosthenes and Against Agoratus ; there, Theramenes is portrayed as treasonous and self-interested, doing tremendous harm to the Athenian cause through his machinations.

De Astronomia was first published, with accompanying figures, by Erhard Ratdolt in Venice, 1482, under the title Clarissimi uiri Hyginii Poeticon astronomicon opus utilissimum This " Poetic astronomy by the most renowned Hyginus, a most useful work ," chiefly tells us the myths connected with the constellations, in versions that are chiefly based on Catasterismi, a work that was traditionally attributed to Eratosthenes.

The first scientific estimation of the radius of the earth was given by Eratosthenes.

Many parts of modern geometry are based on the work of Euclid, while Eratosthenes was one of the first scientific geographers, calculating the circumference of the earth and conceiving the first maps based on scientific principles.

The two towns were separated by one degree on the meridian, so from his measurement he was able to calculate a value for the circumference of the earth – a feat celebrated in the title of his book Eratosthenes Batavus ( The Dutch Eratosthenes ), published in 1617.

The general views of the De situ orbis mainly agree with those current among Greek writers from Eratosthenes to Strabo ; the latter was probably unknown to Mela.

It was notable for its famous librarians: Demetrius, Zenodotus, Eratosthenes, Apollonius, Aristophanes, Aristarchus, and Callimachus.

1241 indicates that Apollonius was succeeded in the position by Eratosthenes ; this must have been after 247 / 246 BCE, the date of the accession of Ptolemy III Euergetes, who was probably tutored by Apollonius and who appointed Eratosthenes.

Several works among the best known during this long period could be cited as an example, from Strabo ( Geography ), Eratosthenes ( Geography ) or Dionisio Periegetes ( Periegesis Oiceumene ) in the Ancient Age to the Alexander von Humboldt ( Cosmos ) in the century XIX, in which geography is regarded as a physical and natural science, of course, through the work Summa de Geografía of Martín Fernández de Enciso from the early sixteenth century, which is indicated for the first time the New World.

* Eratosthenes ( 276194 BC ), who made the first known reliable estimation of the Earth's size.

* The first good measurement of the distance between Earth and the Sun is made by Eratosthenes ( approximate date ).

The Return of the Heracleidae, which is the closest event to a Dorian Invasion available in legend, must coincide with the entry of Aristodemus and his brethren into Arcadia, which, based on the chronology of Eratosthenes, happened 328 years before the generally accepted date of the first year of the first Olympiad, 776 BC.

The Return of the Heracleidae, which is the closest event to a Dorian Invasion available in legend, must coincide with the entry of Aristodemus and his brethren into Arcadia, which, based on the chronology of Eratosthenes, happened 328 years before the generally accepted date of the first year of the first Olympiad, 776 BC.

The first known grade measurement was performed by Eratosthenes ( 240 BC ) between Alexandria and Syene in what is now Egypt, determining the radius of the Earth with remarkable correctness.

The first person to use the word " geography " was Eratosthenes ( 276-194 BC ).

Eratosthenes was the first to write on physical geography ; he also first attempted to draw up a chronological table of the Egyptian kings and of the historical events of Greece.

The founder of the mathematical school was the celebrated Euclid ; among its scholars were Archimedes ; Apollonius of Perga, author of a treatise on Conic Sections ; Eratosthenes, to whom we owe the first measurement of the earth ; and Hipparchus, the founder of the epicyclical theory of the heavens, afterwards called the Ptolemaic system, from its most famous expositor, Claudius Ptolemy.

On the surface it appears that Eratosthenes altered the base line to pass through the northern extreme of Celtica.

As noted in the book Huai Nan Zu, in the 2nd Century BC Chinese astronomers effectively inverted Eratosthenes ' calculation of the curvature of the Earth to calculate the height of the sun above the earth.

< p > Strabo ... enters largely, in the Second Book of his Geography, into the opinions of Eratosthenes and other Greeks on one of the most difficult problems in geology, viz., by what causes marine shells came to be plentifully buried in the earth at such great elevations and distances from the sea .</ p >

Ptolemy discussed and favored this revised figure of Posidonius over Eratosthenes in his Geographia, and during the Middle Ages scholars divided into two camps regarding the circumference of the earth, identified with Eratosthenes ' calculation on the one hand and Posidonius ' 180, 000-stadium measure on the other.

* Eratosthenes: calculated the size of the earth and its distance to the sun and to the moon

When the Sun is directly overhead, however, Eratosthenes visually blends into the surroundings, and it becomes more difficult for an observer to locate it.

Those factorization methods use the idea of the sieve of Eratosthenes to determine efficiently which members of a list of numbers can be completely factored into small primes.

Eratosthenes used a simpler sexagesimal system dividing a circle into 60 parts.