Page "Jacob's staff" Paragraph 8

The original Jacob's staff was developed as a single pole device in the 14th century that was used in making astronomical measurements.

It was first described by the Jewish mathematician Levi ben Gerson of Provence.

However, its invention was likely due to Jacob ben Makir who also lived in Provence in the same period.

Attributions to 15th century astronomer Georg Purbach are less likely correct, since Purbach was not born until 1423.

Such attributions may refer to a different instrument with the same name.

May states that its origins can be traced to the Chaldeans around 400 BC.