Notes on Hebrew Lists of Geographical Coordinates of Cities

Two late medieval Hebrew manuscripts that include lists of the longitudes and latitudes of cities are of interest because they explain the use of two different prime meridians that are 171/2 degrees apart. It is argued that the discussion in one Hebrew manuscript is a translation of a Latin text of unknown authorship, published in 1483, but which must have already been available in 1460, the date of the Hebrew translation.