it being the middle of the night , and they both being at something of a loose end , the ward sister made the inspector coffee and they spoke awhile : of her job , and how the nightshifts could sometimes be little more than being on call but at work so different from the hectic days but how this gave her the time to get so much done ; and of how her ward inspections at this time were silent walks down empty corridors on rubber soles , doors found by torchlight and opening on oiled hinges , her feelings almost maternal as she cast a carers gaze over her nocturnal charges .