True to the advertising dictum that no flat surface goes unexploited, the sign facing the camera, if magnified significantly and shaded darkly, reveals itself to be a billboard, of sorts, for something called Swift's Pride Soap and Washing Powder. My research shows that this was, more or less the Comet cleanser or Dawn dishwashing liquid of its day. For all I know, these could have been as plentiful as the Mail Pouch Tobacco or the See Rock City signs painted on barns across the country. Still, it seems a bit incongruous to have one placed here in the middle of the Fox River.
1908 print ad for Swift's Pride