Ancient Greek drama--the plays of Aeschylus, Sophocles, Euripides, and Aristophanes--was performed by actors and a chorus wearing full masks. (You can read my brief introductions to Greek drama and the playwrights.) We have archaeological evidence for what the ancient stage was like, and we have the plays themselves as evidence for the number of actors and many other stage conventions.
But the masks themselves present a problem: whatever they were made of has not survived in the archaeological record. We have no surviving technical manuals that describe mask construction. And the best contemporary imagery we have--on vases--is problematic, too. If a mask depicts someone wearing a mask, it "melts" onto the actor, and it's difficult to see that it's a mask and not just the actor's face. Even those few vases we have that show actors holding their masks (the Pronomos vase is the most famous) show very little detail about how the mask was made, how it attached to the head, how big the holes for eyes and mouth were. The ancient secondary textual evidence is scanty and later than our plays.
As someone who directs Greek plays and who feels that we understand plays better the more we use the conventions for which they were written, I think it's important, if we can, to find out how the Greeks made their masks so that we can make them for our productions. This blog will chronicle a summer research project designed to do just that.