Medieval astronomers used tables to solve most of the problems they
faced. These tables were generally assembled in sets, which constituted
genuine tool-boxes aimed at facilitating the task of practitioners of
astronomy. In the early fourteenth century, the set of tables compiled
by the astronomers at the service of King Alfonso X of Castile and Leon
(d. 1284), reached Paris, where several scholars linked to the
university recast them and generated new tables. John of Ligneres, one
of the earliest Alfonsine astronomers, assembled his own set of
astronomical tables, mainly building on the work of previous Muslim and
Jewish astronomers in the Iberian Peninsula, especially in Toledo. Two
major sets had been compiled in this town: one in Arabic, the Toledan
Tables, during the second half of the eleventh century, and the
Castilian Alfonsine Tables, under the patronage of King Alfonso. This
monograph provides for the first time an edition of the Tables of 1322
by John of Ligneres. It is the earliest major set of astronomical tables
to be compiled in Latin astronomy. It was widely distributed and is
found in about fifty manuscripts. A great number of the tables were
borrowed directly from the work of the Toledan astronomers, while others
were adapted to the meridian of Paris, and many were later transferred
to the standard version of the Parisian Alfonsine Tables. Therefore,
John of Ligneres' set can be considered as an intermediary work between
the Toledan Tables and the Parisian Alfonsine Tables.
