When the 1st century AD Roman glass pitcher arrived at the Centre Archéologique de Vienne in the spring of 1982, it was in a very bad state having been put together with water-soluble glue from nine separate pieces with missing parts filled in with plaster darkened with anthracite, the result of poor workmanship possibly dating back to the late 19th century. This rare quality Roman vessel (height: 14cm) shows a white inlay of a scene from the Priapic cult on a dark purplish red background. The author describes in detail the techniques for freeing the original pieces from later additions, removing the products of corrosion, reconstituting the vessel to the extent possible, harmonizing its surface while protecting it from further corrosion, and thus coming near its appearance in antique times. -- AATA