In late 1930s Britain, a young woman yearns for the exciting adventures that seem to be reserved exclusively for men. "Come visit me in India," her friend Alexa writes, and Ursula Graham Bower does, unaware that Assam is where her dreams will come true.Flouting convention, she goes to live in the jungle-clad hills with reformed headhunters, the Zemi Nagas, where she finds fulfillment and a sense of purpose by recording their culture and providing...