The brainwave to create castrati had first occurred two centuries earlier in Rome, where the pope had banned women singing in churches or on the stage. Their voices became revered for the unnatural combination of pitch and power, with the high notes of a pre-pubescent boy wafting from the lungs of an adult; the result, contemporaries said, was magical, ethereal and strangely disembodied. But it was the sudden popularity of Italian opera throughout 1600s Europe that created the international surge in demand. Italian boys with promising voices would be taken to a back-street barber-surgeon, drugged with opium, and placed in a hot bath. The expert would snip the ducts leading to the testicles, which would wither over time. By the early 1700s, it is estimated that around 4,000 boys a year were getting the operation; the Santa Maria Nova hospital in Florence, for example, ran a production line under one Antonio Santarelli, gelding eight boys at once.
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