Was it a talisman? A calendar? An astronomical observatory? A fabric pattern? A pagan idol? An ancient tattoo “flash”? Or the key to saving mankind? The Cincinnati Tablet has invited many interpretations since its discovery in 1841.

The rectangular slab of sandstone, inscribed with convoluted symbols on its face and deep grooves on its back, is on display at the Cincinnati Museum Center today. You may need to exert some effort in finding the tablet in its out-of-the-way nook.

When Cincinnati was first settled, a number of “Indian mounds” punctuated the mostly flat basin around the growing village. A map appended to Daniel Drake’s 1815 “Statistical View of Cincinnati” lists almost a dozen, including a huge mound that occupied almost all the land between Race and Walnut streets, extending north of Fifth Street and south of Fourth Street.

A small mound lay out on what was then the western edge of Cincinnati, on land then owned by surveyor Joseph Gest, for whom Gest Street is named. The street that ran up to it was called Mound Street (a small section of which remains) and the mound caused Mound Street to terminate at Fifth Street. Henry A. Ford, in his 1881 History Of Cincinnati, Ohio, With Illustrations and Biographical Sketches, describes its discovery:

“In November, 1841, the large tumulus near the corner of Fifth and Mound streets was removed, in order to extend Mound street across Fifth and grade an alley. A little above the level of the surrounding surface, near the centre of the mound, were found a large part of a human skull and two bones of about seven inches length, pointed at one end. It was undoubtedly the grave of a Mound Builder, probably a great dignitary of his tribe. Under the fragmentary skull of the buried Builder was a bed of charcoal, ashes and earth, and therein a very remarkable inscribed stone which, after much discussion, including the publication of Mr. Clarke’s interesting pamphlet in vindication of its authenticity, has been pronounced a genuine relic of the period of the Mound Builders.”

As Ford suggests, the Cincinnati Tablet was initially proclaimed a fake and a fraud. This was a period when American cities took great pride in their antiquities (even while demolishing them for road improvements) so a debate raged for some time until the 1876 publication of The Pre-Historic Remains Which Were Found On The Site Of The City Of Cincinnati, Ohio With A Vindication Of The “Cincinnati Tablet” by Robert Clarke, a Cincinnati publisher and bookseller. Clarke traced the provenance of the artifact in such detail that its authenticity was accepted. The Cincinnati Tablet was donated to the Historical Society by Joseph Gest’s son, Erasmus.

Since the publication of Clark’s book, several similar tablets have been discovered at locations associated with the Adena people who lived in Ohio from about 1000 BC to about 200 BC.

Ford related theories then-current (1881) that the tablet might have been a calendar or a stamp for marking fabric or leather with a design. He also noted the resemblance to Egyptian artifacts that were just then catching the public’s attention.

In recent years, anthropologist William Romain and other scholars have developed detailed analyses of the geometry of the Adena tablets. Romain suggests that the Cincinnati Tablet was used to locate the rising of the sun and moon at key times of the year.

Another interpretation, proposed by amateur archaeologist Frank Otto and others, is incorporated into the Ohio History Connection’s online survey of Adena culture:

“Besides being made of sandstone, the Berlin, Wilmington, Keifer, Cincinnati, and Low tablets are grooved on the back side much like whetstones, which were used for sharpening bone needles. This suggests that the tablets could have been used for tattooing. The engraved surface, covered with paint, could be pressed against a person’s body, stamping it with the image. Then the design could be tattooed into the skin using fine bone needles sharpened in the grooves on the back side of the tablet.”

Other interpretations of the Cincinnati Tablet and the other Adena tablets have been all over the intellectual map. One investigator notes that the Cincinnati Tablet has several dots, arranged in groups of eight, six, four and two and somehow connects this to the diameter of the Sun (864,336 miles). Yet another finds “several fetal designs that have been interpreted as symbolical of those gestative and procreative mysteries that must have powerfully affected the minds of man in the remotest early ages.” Yet another theory is that the Cincinnati Tablet “speaks a universal language … the master key of all the mound builders’ mysteries, wonderful culture and high intelligence shown and handed down to civilization of the present day for our good and welfare.” Speculation has been published that the Cincinnati Tablet and related stones were Masonic talismans, or related to the horned serpent idols of Central America, or a predictor of global magnetic reversals. And then there is one student who concluded, “scholarship is dumb and imagination is the only interpreter of these strange mementos.”

