See quotation.

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1833.  Two hundred dollars worth of dogs! said I to myself—two hundred dollars worth of dogs!!—What does that mean? Upon asking for an explanation, I found out that bonds, or promissory notes, were termed dogs—and they were said to be of a good or bad breed, according to the ability and punctuality of the obligor.—‘Sketches of D. Crockett,’ p. 121 (N.Y.). This use is obsolete.

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