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Their housekeeping was of a very frugal kind: not only because that was the safest way of life, involving the least offence to the people, but because they were not rich, and Charles, throughout his imprisonment, had had to pay heavily for his bad food, and for his guard, and towards the living of the poorer prisoners. Partly on this account, and partly to avoid a domestic spy, they kept no servant; the citizen and citizeness who acted as porters at the courtyard gate, rendered them occasional service; and Jerry (almost wholly transferred to them by Mr. Lorry) had become their daily retainer, and had his bed there every night.