A repository of Stargate coordinates, presumably for all known Stargates that had been charted by the Goa'uld when it was created. The only known cartouche exists in a map room hidden on Abydos, and was presumably placed there by Ra.
The cartouche served as the first (and primary) source of valid Stargate addresses for Stargate Command, in the early years of its operation.
Children of the Gods - Dr. Daniel Jackson unveils the chamber that contains the Abydos Cartouche, giving Earth the unexpected opportunity to visit countless new worlds.
The Fifth Race - Under the influence of the Ancients' repository of knowledge, Jack inputs new gate coordinates into the dialing computer -- for planets not found on the Goa'uld's cartouche on Abydos.