Ancient Egyptian Engineering Techniques

Over 4,000 years ago, ancient Egyptian masons drilled

perfectly circular core holes through solid granite using tools

made of soft copper. Granite is loaded with hard quartz crystals,

meaning

soft copper chisels instantly blunt against it.

Yet ancient sarcophagi and temple blocks feature deep round holes

with spiral

grooves inside. Egyptian engineers solved this by using

hollow copper

tubes mounted on weighted bow drills.

To cut the granite, they poured a continuous slurry of sharp

quartz sand and

water. As the copper tube spun, the soft metal picked up the

quartz grains into its rim. The spinning quartz crystals acted as

teeth,

grinding down the granite while the water flushed away the rock

dust.

By using copper as a holder for hard quartz grains and flushing with water,

ancient Egyptians used physics to drill solid granite four millennia

before diamond-tipped drills. Uncovering the secrets of ancient

engineering, from massive monuments to complex vintage

mechanisms.

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