“... many outstanding problems. How were they to synchronise Nabonassar’s era with eras not found in Ptolemy? Was the Olympiad year 776 or 775? Was Funck right in his use of Ptolemy to criticise Copernicus? Was the Attic year lunar or not? Did the Jews borrow their calendar from the Babylonians, so that a whole tradition would ...”

“... a ‘progressive encompassment’ of the new sea. This culminated in the second century ce with Ptolemy of Alexandria in his Geography enclosing the Indian Ocean entirely with a fictional southern coast. It began, however, with Agatharchides of Cnidus who worked at Alexandria in the mid-second century bce. His On the Erythraean Sea is the earliest known ...”

“... library to rival that of Alexandria; at its peak it contained 200,000 volumes. According to Pliny, Ptolemy of Egypt was so enraged by his neighbour’s acquisitive habits that he banned the sale of papyrus. Eumenes instructed his subjects to find an alternative writing material, and parchment was born. Where plant-based papyrus was fibrous, brittle and liable ...”

“... or even planned – of a skeleton hurling a spear. It would also fit with the impression left by Ptolemy Dean’s attractively gentle watercolours, which he includes as illustrations to Sir John Soane and the Country Estate (a careful study of ten of Soane’s best-preserved country house schemes). These prove, as clearly as anyone could wish, that a ...”

“... act of hubris. Celestial models didn’t only provide opportunities for philosophical discourse. Ptolemy wrote a treatise on Planetary Hypotheses, which addressed the problem of how to create models of the heavens that would reflect current astronomical knowledge. He seemed to regard them as scientific instruments and teaching aids. While not common ...”

“... scholars and scientists, complementing the more authoritative but less entertaining works of Ptolemy. The Greek humanist Gemistos Plethon brought a copy of Strabo with him to the 1439 ecumenical council in Florence that attempted a reunification of eastern and western churches; he lectured on Strabo to Florentines between council sessions. In this way ...”

“... by laughter unto death; for those affected in this way, the remedy is to drink from the other.’ Ptolemy identified the Canary Islands as the Islands of the Blessed and used them as a reference point for defining the zero meridian. In 1851 the astronomer George Airy identified Greenwich as the prime meridian. Did he believe it was also set on a blessed ...”

“... and sacked Gaza in 332 bce. Following his death, Gaza came under the control of his general Ptolemy, now king of Egypt, and from around 200 the Syrian Seleucids. Perhaps this was when a gorgeous marble Greek goddess was lost off the coast of Gaza, to be retrieved in the 20th century by a local fisherman. Clothed in a long draped dress and a cosy-looking ...”

“... chapters illustrate ‘how the ideas of ancient auctores – Pythagoras, Hippocrates, Aristotle, Ptolemy, Augustine, and the rest – flowed through the Middle Ages in many different channels: sermons and Bible commentaries, moral and political treatises, encyclopedias and lexicons, medical and astrological handbooks, didactic and courtly poetry, tapestries ...”

“... exactly could claim to have solved the ‘mystery of the Nile’, a mystery that had first gripped Ptolemy. Ancient Egyptian prosperity was built on the annual summer flooding of the river and the fertility produced by its silt. To be so heavily dependent on this miraculous annual event without knowing its ultimate source was a cause of unease for successive ...”

“... had been determined by tradition and empirical evidence dating back at least to Posidonius and Ptolemy. Another figure would later have been calculated, when the information became available as to the exact time the ships had left port. Perhaps even more enviable would have been Ashmole’s certainty that his position was fully integrated within the chain ...”

“... century, Edmond Halley examined records of medieval and ancient solar eclipses back to the time of Ptolemy. He discovered that when he used the position and trajectory of the Moon to determine retrospectively when solar eclipses should have occurred, the times calculated differed from the actual ones by up to an hour. Halley deduced that in the past the Moon ...”

“... three thousand years? As a matter of fact, we know that, latterly, they did try to adjust: under Ptolemy III, for example, leap years were officially introduced, but they proved unpopular. Any earlier adjustment, if it won acceptance, would have been enough to wreck the modern chronological calculations. There is another obstacle, though – the ...”

“... It starts with Greco-Roman culture, in particular the cartography of the Alexandrian scholar Ptolemy, who knew the world was a globe and thought the best way to project it was as a grid. On such a map, the vertical lines of longitude converge naturally at two poles (the choice to put north on top seems to have been purely a matter of custom). Like the ...”

“... with ‘hair tightly curled, lips thick, colour dark’. In Alexandria, in the second century ce, Ptolemy synthesised the research of his colleagues and reports from merchants to imagine a central Sahara – he calls it Inner Libya – whose population was a mixture of white and black. In his stab at physical anthropology, the Sahara was inhabited by tribes ...”