Achille is a bronze 12-pound cannon created in 1746 in Lyon by founder Jean II Maritz, Master of the Foundries of France.
The arrangement of decoration around the entirety of the firearm aligns with the royal order of October 7, 1732, and this piece is signed by Jean-Florent de Vallière (1667–1759).
This rich decoration is placed in such a way that the tailpiece has been sculpted to depict the head of gallinaceous bird. The first reinforce bears the French coat of arms and the sun, given that it was the king's personal emblem, along with the motto "NEC PLURIBUS IMPAR (Not Unequal to Many)." The dolphin-shaped handles are attached to the second reinforce; finally, the barrage bears the coat of arms of the Grand Master of the Artillery, the weapon's motto Ultima Ratio Regum (The Last Argument of Kings) and the name of each part.
This cannon has the particularity of having been grooved towards the end of the 1860s, so that it could fire oblong shells.