What new technique did Houdon accomplish in his sculpture to make his figures look more lifelike?

Question

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Answer 1

Houdon's ability to "do" eyes stunned viewers in the 18th century as it will today's audiences. He was the first sculptor in the history of art who knew how to render the way eyes capture the light. How did he do it? He first cut out the entire iris, and then bore a deeper hole for the pupil, taking care to leave a small fragment of marble to overhang the iris. The effect is a vivacity and mobility of expression unrivalled in the long history of portrait painting or sculpture.