sidero

"They built hard coverings for themselves. They wanted to be stronger too, for war and work on deck. Then they put the liquid you saw into us so that our arms and legs would move as they wanted, but with greater force. Into our generators, I ought to have said. They needed to communicate, so they added talk circuits. Then more circuits so we could do one thing as they did another. Controllers so we could speak and act even when they could not. Until at last we spoke in storage and acted without a mate inside."

Gene Wolfe, The Urth of the New Sun.