Holmes' Latin quotation

“I have all the facts in my journal, and the public shall know them. In the meantime you must make yourself contented by the consciousness of success, like the Roman miser —
“Populus me sibilat, at mihi plaudo Ipse domi simul ac nummos contemplar in arca.” (
Sherlock Holmes)

Explanation:
The quotation is from Horace, Book 1, Satire 1.
"The public hisses at me, but I applaude myself in my own house, and simultaneously contemplate the money in my chest."

Jarveys

"All these considerations led me to the irresistible conclusion that Jefferson Hope was to be found among the jarveys of the Metropolis." (Sherlock Holmes)
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London growler

"The ordinary London growler is considerably less wide than a gentleman’s brougham." (Sherlock Holmes)
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South American arrow poison

"I was once janitor and sweeper-out of the laboratory at York College. One day the professor was lecturing on poisons, and he showed his students some alkaloid, as he called it, which he had extracted from some South American arrow poison, and which was so powerful that the least grain meant instant death." (Jefferson Hope)
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Gin palace

"The craze for drink had seized him (Enoch Drebber) again, and he ordered me to pull up outside a gin palace." (Jefferson Hope)
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Liquor shops

“He (Enoch Drebber) walked down the road and went into one or two liquor shops, staying for nearly half an hour in the last of them." (Jefferson Hope)

This would not be a shop as understood these days but somewhere you could actually stay to drink as well as buy liquor.