Rhytons are a glass drinking vessel that extends beyond the Roman Empire and the location. There are several styles, but at its core a rhyton is shaped like a horn and has animal motifs. A horn is by no means a unique design for a drinking vessel as drinking horns go back to neolithic times, and then up through Roman times, the Norse culture, and up to the Middle Ages. A curious quirk about some is that they have an opening at the tip of the horn. This allows for drinking from the bottom (see the picture below). This could be a more time specific feature but it appears in finds from not only Ancient Rome but Paratha, Syria, and Malta as well. Their purpose is, Were they used for ceremonies, festivals, or just for drinking. With the opening at the bottom, what seems to be a Roman feature/influence, the drinker was logically prohibited from neglecting their drink. However, being that it was Rome, some speculate that a servant (likely a slave) would have to stand nearby with their finger over the hole.