Which brings us back to that wooden toe from Cairo. The earliest prosthesis seemed to have no intention of bettering nature. Instead, it, and the devices that would soon follow, treated the body as a kind of platonic model, molding themselves according to the curves and planes of the human form. It wasn't until later—much, much later—that we began to think beyond the lifelike.

The Cairo Toe, 700-950 B.C.

The Cartonnage Toe, 600 B.C.

The Cartonnage Toe (The Lancet)

This toe, also Egyptian and dating a couple hundred years after the Cairo toe, is composed of cartonnage, a papier-mache-like substance made from linen, plaster, and glue. While the Cairo Toe was likely an ancient mobility aid, the cartonnage toe was likely used for cosmetic purposes. As the Wellcome Collection puts it, "The fact that it does not bend seems to imply it was used for the sake of appearances only and did not help the wearer to walk correctly."

Roman artificial leg, 300 B.C.

The Capua Leg (sciencemuseum.org)

The image above is a replica of an artificial leg found in a Roman grave in Capua, Italy. The leg, discovered in 1910, dates from 300 BC. (Why is the image a replica? The historical version of the limb, after its discovery, was kept at the Royal College of Surgeons in London, where it was destroyed in a World War II air raid.)

War Prostheses of the Middle Ages and Renaissance

Götz's artificial arm, 16th century (myarmoury.com)

During the Middle Ages, wars were conducted using swords and other weapons that swiped and otherwise crushed limbs. This, combined with the fact that missing limbs were often considered to be shameful deformities, led to innovations in prosthetics. Artificial limbs, as extensions of knights' suits of armor, began to be constructed of iron.

And yet they were still lifelike—as in the prosthetic arm above and below, created for the Franconian Knight Götz von Berlich after a cannonball took his left arm in 1504. Here's a closeup of the limb:

Götz's artificial arm, 16th century (myarmoury.com)

Note, again, the nail beds. And the knuckle creases. This is a tool—the fingers are curved to grip a sword—that is also, in a meaningful if not fully literal way, a hand.

This also makes the tool, as a prosthesis, conscribed to its time. We have, with our creative adaptations of new technologies, moved beyond simple biomimicry. We have moved into a new realm of human augmentation. As Gear Patrol summed it up: "The real question the world should be asking isn’t 'will prosthetic science match what evolution spent 200,000 years perfecting?', but rather, 'when will it surpass it?'"

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