Originally Posted by dwright
"What I'd like to know is How did the Greeks and their contemporaries to it???"
Read the autobiography of Benvenuto Cellini for an excellent description of the casting process of a larger than life bronze during the renaissance.
Bienvenuto=literally, "it's good to see you" also meaning--"you are welcome" Cellini-------why don't we feel the freedom to thusly name our children?
(thoughts of Abbot and Costello's "who's on first?")
If memory serves,
most of the description of the casting process wasn't about the mold, but rather, had to do with adjusting the bronze so that it would flow just right to reach the far corners of the Perseus mold----first, they undercooked it, then got some cured oak and overcooked it(and set the roof on fire), then it began to curdle, and he had to throw in his pewter plates and tableware to relax the alloy----high adventure indeed and a wondrous read.
I was under the impression that the greeks used a packed sand mold---but haven't really researched it.