The Devil Man by Edgar Wallace

A remarkable woman was Madame Stahm: she was indefatigable, tireless.

Baumgarten, who, curiously enough, never spoke good German, called her the Wonderfrau. She could live on the minimum of sleep; she ate no more than would have kept a canary alive; and, except for these hysterical outbreaks of hers, did not know a day's sickness. She had an unusual knowledge of mechanics, was a particularly brilliant chemist, though she had taken no degree in the subject, and during her married life had acquired some of her husband's uncanny instinct which is nine-tenths of inspiration.