Mysteries of the Hopewell: Astronomers, Geometers, and Magicians of the Eastern Woodlands

Appendix: The Serpent Mound

Appendix T H E S E R P E N T M O U N D Nestled deep in the hills of southern Ohio, high up on a lonely ridge, is a monster serpent. Known as the Serpent Mound, this prehistoric earthwork is one of the world’s largest effigy mounds (see figure a.1). It is not certain who built the Serpent Mound. Early archaeologists (Greenman 1934; Webb and Snow 1945) suggested that the effigy was built by the Adena people sometime between 800 b.c. and a.d. 100. However, Robert N. Converse (1979:3), editor of the Ohio Archaeologist , has noted that the effigy looks more like Hopewell than Adena. More recent investigators (Fletcher et. al. 1996) have proposed that the effigy was built by Fort Ancient peoples sometime around a.d. 1070±70. Their opinion is based on two radiocarbon dated samples recovered from within the serpent’s body. My purpose here is not to argue the date of the Serpent Mound. However, it may be that the charcoal samples recovered by Fletcher and Cameron’s team were inadvertently recovered from layers of earth that were added to the earthwork in the late 1800s. These layers of earth were added to the effigy by Frederick W. Putnam of the Peabody Museum in an effort to restore the Serpent Mound to its original height. What Putnam did was to scrape up earth from the surrounding area and heap this earth onto the body of the effigy. We know from archaeologist James B. Griffin’s (1943) work at the site that, in addition 233 to Adena people, Fort Ancient people also occupied the Serpent Mound ridge. Given this, it seems possible that in spite of the attention given to this problem by Fletcher and his team, the charcoal fragments that yielded the late Fort Ancient dates may still have come from earth that had been scraped up and deposited on the effigy by Putnam. In my opinion, the effigy is of Hopewell origin. This opinion is based on several observations. First, the structure exhibits a geometric complexity that is more typical of Hopewell than either Adena or Fort Ancient. Second, as I will show, there is clear evidence that the Serpent Mound builders used lesser multiples of the 1,053-foot unit of length commonly used by the Hopewell. Third, as I will also demonstrate, the serpent effigy incorporates various astronomical alignments, including 234 a p p e n d i x Fig. a.1. Aerial view of the Serpent Mound. Photo by the author. alignments to the moon’s mid-point as well as maximum and minimum rising and setting points. These lunar alignments appear to be exclusive to the Hopewell. However, because of the uncertainty as to the effigy’s date and origin, my Serpent Mound findings are included herein as an appendix, rather than incorporated into the main body of the text which deals with generally accepted Hopewell earthworks. putnam’s restoration The first published map of the Serpent Mound was made by Squier and Davis (1848), based on a survey they made in 1846. In the years following their visit, however, the ridge that the serpent rests upon was cleared for cultivation, planted with crops for a brief time, and grazed by cattle. In 1883, Frederick W. Putnam of the Peabody Museum visited the Serpent Mound and soon thereafter began restoration work. Putnam was conservative in his efforts and limited his excavations of the effigy to the edges of both sides along the length of the earthwork and several trenches cut perpendicularly through the effigy. As Putnam (1892:181) explained, he merely threw back, onto the original embankments, the earth that had “washed down” from the mound. Importantly, Putnam (1890:875) also noted that “the several plowings had not disturbed the underlying clay of which the embankments were constructed.” By excavating along the edges of the effigy, Putnam was able to distinguish between the undisturbed, compact yellow clay stratum of the mound and the looser, dark topsoil that had washed down. As Fletcher (1996:113) and his team explain, Putnam “noted the presence of an underlying layer of mixed clay and ashes—apparently used by the builders to lay out the shape of the embankment—and used that outline as a guide.” In this way, Putnam...