In a Mexican book of 1834 on statistics[1] both the ps and the $ are used. Our $ was introduced into Hawaii by American missionaries, in a translation of Warren Colburn's "Mental Arithmetic" in 1845.[2]
The transition from the florescent ps to our dollar mark is seen in Fig. 4. Apparently it is a change introduced unconsciously, in the effort to simplify the complicated motion of the pen called for in the florescent ps. No manuscript on this point is so interesting and convincing as the two contemporaneous copies, made by the same hand, of a letter written in 1778 by Oliver Pollock, then "commercial agent of the United States at New Orleans." Pollock rendered great services to the United States, being to the west what Robert Morris was to the east. Pollock's letter is addressed to George Roger Clark, who was then heading an expedition for the capture of the Illinois country. Both copies of that letter show the $ in the body of the letter, while in the summary of accounts, at the close, the $ and the florescent ps. are both used. These documents show indeed "the modern dollar mark in the making." In the copy from which our photograph is taken, Pig. 4, the 8613 dollars is indicated by the regular $, while in the other copy it is represented by the fancy ps. Carefully examining the two symbols in our photograph, we see that the ps is made by one continuous motion of the pen, in this order: Down on the left—up on the right—the loop of the p—the s above. On the other hand, the $ symbol is made by two motions: One motion down and up for the p, the other motion the curve for the s, one symbol being superimposed upon the other.
Thus the origin of the dollar mark is simplicity itself. It is an evolution from ps. When the p was made by one long stroke only, as in Fig. 3, Nos. 12, 14, 17, 20, then the $ took the form $, as used by Robert Morris (Fig. 3, No. 21). Before 1800 the regular mark $ was seldom used. In all our researches we have encountered it in eighteenth-century manuscripts not more than 15 or 20 times. None of these antedates the ones in Oliver Pollock's letter of 1778. But the dollar money was then very familiar. In 1778 theater prices in printed advertisements in Philadelphia ran, "Box, one dollar." An original manuscript document of 1780 gives 34 signatures of subscribers, headed by the signature of George Washington. The subscribers agree to pay the sum annexed to their respective names, "in the promotion of support of a dancing assembly to be held in Morristown this present winter." The sums are given in dollars, but not one of the signers used the $ symbol; they wrote "Dollars," or "Doll," or "Ds."[3]
