Rather than injecting further red herrings, it would be useful if he could elaborate on how he resolves this major dichotomy. Before continuing with ancient Egyptian artifacts, though, let me describe a modern technique of machining that is little known or used in most machine shops today. Now remember, we are not in ancient Egypt now, so you can accept what I am saying as demonstrated fact. Remember also that there are other readers of these posts who are my peers - engineers, machinists and toolmakers. So I'm not trying to pull the wool over your eyes.
Dielectric oil flushes the waste material away.
The copper or graphite electrode actually burns the material leaving behind an impression of its shape. The round copper rod has a helical thread cut into its outside diameter, like a bolt. An assembly with a nut is attached to the ram platten of the machine. I draw on this analogy to explain my theory on ultrasonic machining. There has to be a means by which pressure is applied to the workpiece.