Author: Science News Staff / Source: Science News
Archaeologist Nicholas Blackwell built a version of a Bronze Age pendulum saw that may have been used to build Mycenaean palaces, Bruce Bower reported in “How a backyard pendulum saw sliced into a Bronze Age mystery” (SN: 4/28/18 & 5/12/18, p.
32).Reader Fredric Blum argued that a pendulum saw’s blade would have dulled too fast to completely cut through stone without having to be replaced, making for an impractical saw.
Ancient Mycenaeans could have used the blades along with crushed emery to cut stone, Blackwell says. Compared with the sand that Blackwell used in his experiment, crushed emery would have embedded in the blade and prevented it from wearing down as fast. But even in his experiment, the blades didn’t completely wear down. “I could have made numerous additional cuts with a single blade before it wore away or became unusable,” he says.
Blackwell adds that the ancient saws were probably selectively used. “It is not as if the Mycenaeans utilized the pendulum saw to cut every block on the citadel. That would have necessitated the continual switching of saw blades on a scale that is hard to comprehend,” he says. Blades would have been changed occasionally, “but not at a rate that would have made the pendulum saw, given its restricted application in Mycenaean architecture and sculpture, unusable or inefficient.”
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