"I may say, however, that Griswold's biography of Poe was (not to mince words) a malicious libel, that he knew this when he printed it. As I told Mr. Griswold this, to his face, I feel no hesitation in stating it to you. The truth is that Griswold hated Poe, but also feared him; however this libel on Poe was kept back till the latter's death. It is, I suppose, what Griswold meant, when he told me once, 'If I survive Poe, I've a rod in pickle for him.' For Griswold was a coward, among other things, and certainly not restrained by any high sense of honor."(A note: "rod in pickle" was a rather quaint old expression simply meaning that Griswold had a revenge lying in wait for Poe.)
-Charles Jacobs Peterson, who had worked with both Edgar Poe and Rufus Griswold on "Graham's Magazine," in a letter to John H. Ingram, March 3, 1880.