A punctual person; one to be depended on.

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1805.  

        I mean to have my Sunday shirt
  Wash’d and mended, early,
And I will be upon the spot.
  As punctual as “Charley.”
Mass. Spy, Feb. 20.    

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1835.  Did not I tell you … that I would not vote on the appropriation bill, but when you came to any thing else, I was ‘Charlie on the spot?’—‘Col. Crockett’s Tour,’ p. 112 (Phila.).

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