Sarah was her only child, and, although at the time of which I am writing she was not yet nine years of age, there was no one in London better suited to the adventurous and perilous existence that Fate had selected for her.  Sarah was black as ink—­that is, she had coal black hair, coal black eyes, and wonderful black eyelashes.  Her eyelashes were her only beautiful feature, but she was, nevertheless, a most remarkable looking child.  “If ever a child’s possessed of the devil, my dear Charlotte,” said Captain James Trent to her mother, “it’s your precious daughter—­she is the devil, I believe.”

“Well, she needs to be,” said her mother, “considering the life that’s in store for her.  We’re very good friends, she and I, thank you.”

They were.  They understood one another to perfection.  Lady Charlotte was as hard as nails, and Sarah was harder.  Sarah had never been known to cry.  She had bitten the fingers of one of her nurses through to the bone, and had stuck a needle into the cheek of another whilst she slept, and had watched, with a curious abstracted gaze, the punishment dealt out to her, as though it had nothing to do with her at all.  She never lost her temper, and one of the most terrible things about her was her absolute calm.  She was utterly fearless, went to the dentist without a tremor, and, at the age of six, fell downstairs, broke her leg, and so lay until help arrived without a cry.  She bullied and hurt anything or anybody that came her way, but carried out her plans always with the same deliberate abstraction as though she were obeying somebody’s orders.  She never nourished revenge or resentment, and it seemed to be her sense of humour (rather than any fierce or hostile feeling) that was tickled when she hurt any one.

She was a child, apparently without imagination, but displayed, at a very early period, a strangely sharpened perception of what her nurse called “the uncanny.”  She frightened even her mother by the expression that her face often wore of attention to something or somebody outside her companion’s perception.

“A broomstick is what she’ll be flying away on one of these nights, you mark my word,” a nurse declared.  “Little devil, she is, neither more nor less.  It isn’t decent the way she sits on the floor looking right through the wall into the next room, as you might say.  Yes, and knows who’s coming up the stairs long before she’s seen ’em.  No place for a decent Christian woman, and so I told her mother this very morning.”  It was, of course, quite impossible to find a nurse to stay with Sarah, and, when she arrived at the age of seven, nurses were dismissed, and she either looked after herself or was tended by an abandoned French maid of her mother’s, who stayed with Lady Charlotte, like a wicked, familiar spirit, for a great number of years on a strange basis of confidante, fellow-plunderer, and sympathetic adventurer.  This French maid, whose name was, appropriately enough,