What does the stool that Eurymachus throws at Odysseus accidentally hit?

The stool accidentally hits a cup-bearer.

"With this he grabbed a stool, But Odysseus, fearing attack, squatted at the knees of Amphinomus of Dulichium, and Eurymachus' missile struck a cup-bearer on the right hand, so that his wine jug fell to the floor with a clang, and he fell back in the dust."