The Blog

A library of stories and sources

From early cities and scripts to beliefs, science, and contested history. Pick a subject, read a guide, and open the material behind it.

Every guide links its sources. We mark what comes from a surviving object, what belongs to a tradition, and what remains a hypothesis.

2 of 96 source guides

Jazira and Yemen 1235–1291 CE

Two thirteenth-century astrolabes: what does an inscription prove?

Compare instruments in London and New York. A dated inscription, a museum record, and a surviving treatise answer different questions about their history.

Damascus and Oxford c. 1366 CE and after

Ibn al-Shatir: which manuscript preserves the relevant theory?

His fourteenth-century planetary theory survives in several manuscripts. His separate work on the astrolabe does not alone prove that his Mercury model reached Copernicus.