For those who're unaware, during the 19th & early 20th centuries, husbands took their wives to physicians to be treated for hysteria. Keep in mind that medical science was far more primitive. Physicians would masturbate wives as treatment for hysteria. Due to increasing hysterical patients, physicians invented vibrator in order to keep up with demand for treatment.

Today we know hysteria as sexual frustration, and hysteria treatment as the female orgasm. Before medical knowledge of human sexuality, sexually frustrated women were thought to suffer from mental ailment.

Here's a link to an article about hysteria and invention of the vibrator as a medical instrument:

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