E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
An apothecary, always trying to say a witty thing, and looking for wit in the conversation of others. When he finds anything which he can construe into point he says, Thank you, good sir; I owe you one. He had
a military taste, and was appointed cornet in the volunteer association of cavalry of his own town. (G. Colman: The Poor Gentleman.)