The inscription reads    zuo baoyi, which may be translated as '   cast this precious vessel.'
The you was one of the most important wine vessels of the late Shang and Zhou period, and along with other bronze vessels made for holding food and wine, was part of the important ritual paraphernalia used at the ceremonies and banquets of the upper echelons of society. However, by the end of the Middle Western Zhou, the you, along with other wine vessels, such as zun and jue, had dissappeared from the repertoire of bronze vessels used for ritual purposes.
A you of similar proportions and with similar cast decoration is illustrated by J. Rawson, Western Zhou Ritual Bronzes from the Arthur M. Sackler Collections, Arthur M. Sackler Foundation, Washington, DC, Arthur M. Sackler Museum, Cambridge, Massachusetts, 1990, vol. IIB, p. 524, no. 74, where other you of this general type, but with different cast decoration, are illustrated, p. 515, no. 72, and p. 520, no. 73.