Linton found the story amusing, apparently, and a mightily relieved Mr. P. went off onto a career of his own, outside of archaeology. But, either Linton didn't tell McKern about the prank or he did tell McKern but McKern didn't believe him. For whatever reason, over the next 25 years or so, at least three publications--and probably a few others--described the Spencer Lake Mound as containing an in situ horse skull.
In 1962, Mr. P., by then a college professor but still with an avocational interest in archaeology, dropped into the office of Robert Ritzenthaler at Milwaukee Public Museum, when the first major monograph for the Clam River Focus (including the Spencer Lake Mound) was being prepared. Mr. P. told Ritzenthaler about his youthful escapade, and
he was quite contrite about it and agreed to prepare a statement of the facts as best he remembered them, after 34 years. A copy of this was sent to McKern, who responded with a statement to the effect that he was convinced that the skull he excavated was not the planted one, but as there was reasonable doubt, he would make some revisions [in the monograph] and suggested that his statement be published. Mr. P., however, requested that neither his statement nor McKern's be published, a request that was honored, until the Griffin review. [Ritzenthaler, Wisconsin Archeologist 45(2):115-116 (1964)].
James B. Griffin Exposes the Prank
Enter James B. Griffin, undeniably doyen of archaeology for the American northeast. In 1964, Griffin wrote a review of the Clam River Focus monograph, and noted that despite the previous publication of a horse skull in Spencer Lake Mound, there was no mention of it in the book. And, so, finally, notwithstanding the high level of embarrassment suffered by Mr. P., with an academic career of his own to maintain, notes by Mr. P., W. C. McKern, and Robert Ritzenthaler describing the story above were published in the Wisconsin Archeologist, and the situation was resolved.
Further evidence (beyond Mr. P.'s complete lack of motive for making this story up) was provided by Walter Pelzer, mammologist at the museum in those days, who looked at the skull and identified it as a western mustang, a horse imported for use on Wisconsin farms in the early 20th century. Pelzer also spotted rodent gnawing on all planes of the skull that suggested to him that it had been exposed to the weather for a while before being buried. Radiocarbon dates of the charcoal recovered from the mound provided a use date for the mound between circa 500-1000 AD.
At no point in these proceedings has any archaeologist ever believed the presence of the horse indicated early Viking presence in the American Midwest. The horse skull only suggested to McKern and others that the Clam River Focus sites (of which Spencer Lake Mound is one) dated to the early historic period (i.e., 1700s). But, because there are publications in dusty library stacks saying there was a horse skull in Spencer Lake Mound, the rumors continue to persist, I suppose on the principle that if it's in print it must be true. But no! despite what you may have heard, as far as the evidence shows, the only Viking presence in the Americas was a failed 11th century colony in Newfoundland called l'Anse aux Meadows.
