In the excited aftermath of the Declaration of Independence, colonial printers prepared multiple copies of the document, often for the purpose of public reading.
The John Carter Brown Library has two copies of the version that was printed at Newport by Solomon Southwick not long after the Fourth of July, according to Ted Widmer, director and librarian at the JCB. One copy bears the date July 12. The other, curiously, bears the date June 13, as if it had been printed in advance of Independence Day. Perhaps the normally cautious printer allowed his hands to move too quickly (in patriotic jubilation?) as he set the type for the wrong month.