Charles Dickens (1812-1870).
“Boz, my signature in the Morning Chronicle, ” he tells us, “was the nickname of a pet child, a younger brother, whom I had dubbed Moses, in honour of the Vicar of Wakefield, which, being pronounced Bozes, got shortened into Boz.”
Who the dickens `Boz' could be Puzzled many a learned elf; But time revealed the mystery, For `Boz' appeared as Dickens' self
Epigram in the Carthusian.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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