 In March 1917, a letter from Pettibone was published in "The Weekly Republican".a newspaper in Cape Girardeau, Missouri, in which Pettibone wrote how the recent American entry into "the war in Europe" (World War I) reminded him of his own early days as a green volunteer, concluding, ‘We thought we were having some army experiences while there, but in comparison with our service after we were assigned and reported for duty in the Department of the Cumberland, it was a picnic.