When the new Lincoln cents came out in 1909 everyone wanted one. Of course, today it is known that the 1909-S with Victor D. Brenner's initials on it was one that would prove valuable. However, even by the 1920s, when this panel from this panel from a "Mutt and Jeff" cartoon appeared, the 1909 issue was still well known. The cartoon was titled "They Better Put a Guard on the Mint."
The joke here being, as shown in a later panel, that Mutt, who finally gets a 1909 in change at cigar store, tries to sell it to Jeff only to find that Jeff was offering $10 for 1,909 Lincoln pennies and he now wanted the other 1,908.