Victorian England: a Jesuit priest writes of wrestling with God at night, limbs entangled; an Anglican sister begs Jesus, her divine lover, to end her aching anticipation of their union; a clergyman exhorts nuns to study the example of medieval women who suffered on the rack in order to become "brides" of Christ. Alongside the march of nineteenth-century progress ran a seemingly paradoxical fascination with a dark, erotically suggestive side of...