|Earthworks And The Moon|
“The earth guards the archaeological record, it can be collected from the ground with respect like any other medicine for the benefit of all, though specialists know how to use it best and they can teach others." Canadian Ojibwa elder translated by Grace Rajnovich in Rites of Conquest, Charles Cleland 1992, p.34.
William F. Romain
The study of prehistoric ideology can be described as proceeding in a hermeneutic spiral. As more pieces of the puzzle are revealed, interpretations are modified and revised in a progressive fashion, until we have a satisfactory understanding (also see Shanks and Tilley [1987:106]).
The following is an updated analysis of the Newark earthwork complex. The present paper differs from earlier efforts (Romain 2005a) in several respects. First, the geometric model has been modified so that the centers of the Great Circle and Octagon are positioned perpendicular to the lunar azimuth extending from Geller Hill. Second, the location and orientation of the Ellipse and Salisbury Square earthworks are accounted for. Third, a new explanation for the orientation of the Wright Square is presented. Lastly, the azimuth for the Great Hopewell Road has been re-evaluated and a new explanation that accounts for the azimuth of Road is presented.
The following exercise demonstrates how the Newark complex might have been designed and laid-out:
With reference to figure 1:
1. Point 1 (note 1) is the apex of Geller Hill. Draw line 1-2 at an azimuth of 52°.2, which is equal to the moon’s maximum north rise position as viewed from the top of Geller Hill (A.D. 100 ±100 yrs., lower limb tangency, apparent horizon elevation of 0°.5, corrected to 1°.34).
2. Draw an arc having a radius of 7 OCDs from point 1 (note 2). (Recall that 1 OCD is equal to 1,054 feet [321.26 m] (Hively and Horn 1982:S8). Seven OCDs equal 7,378 feet [2,248.81 m].) Label this arc line 3-4.
3. Draw line 5-6. Make line 5-6, 7 OCDs in length. Situate line 5-6 so it is perpendicular to line 1-2, bisected by line 1-2, and 654.4 feet (199.46 m) from arc line 3-4 as measured along line 1-2. The distance of 654.4 feet (199.46 m) is one-half the diagonal of a square having sides equal to 925.5 feet (282.09 m). (The sides of the ideal Wright Square are each 925.5 feet [282.09 m] in length. The relationship between the 925.5-foot [282.09 m] length and the OCD is explained below, in step 20.)
4. Establish point 7 at the intersection of line 5-6 and arc line 3-4.
5. At point 5, construct a square having sides 1 OCD in length. Orient the square so its diagonal falls on line 5-6.
6. Construct an octagon around the square. Do this by drawing a series of arcs, each having a radius equal in length to the diagonal of the square. (Diagonal of square = 1,490 feet [454.15 m].) Use each of the square’s corners as the center for each arc. Connect the intersection points of the arcs by straight lines, thereby creating an octagon.
7. From Octagon point 8, draw a line perpendicular to line 5-6. Label this new line 8-9. Since line 8-9 is parallel to line 1-2, the Octagon is lunar aligned.
8. Locate the center of the Octagon and label it point 10.
9. Locate points on line 8-9 that are 1 and 2 OCDs respectively, from point 10. Label these points 11 and 12.
10. Construct a circle on line 8-9 using points 11 and 12 to establish its diameter. The diameter of the resulting circle will be 1 OCD – equal to the diameter of the Observatory Circle.
11. Construct a circle having a diameter of 1,178.4 feet (359.18 m) – equal to the size of the Great Circle. (The diameter of 1,178.4 feet (359.18 m) for the Great Circle is equal to the hypotenuse of a right triangle having sides equal to 1 OCD and ½ OCD, respectively.)
12. Position the center of the Great Circle at earlier established point 7.
13. From point 10 at the center of the Octagon, draw an arc having a radius of 7 OCDs. Label this arc line 13-14.
14. From point 10 at the center of the Octagon, draw a line through point 8 to arc 13-14. Label the end of this line point 15.
15. From point 15 draw an arc having a radius of 7 OCDs. Label this arc line 16-17.
16. From point 5 on the Octagon, draw an arc having a radius of 7,070.4 feet (2,155.06 m). Label this arc line 18-19. The length of 7,070.4 feet (2,155.06 m) is related to the OCD in the following way. The hypotenuse of a right triangle having sides equal to 1 OCD and ½ OCD is 1,178.4 feet (359.18 m). Accordingly, 6 x 1,178.4 feet (359.18 m) = 7,070.4 feet (2,155.06 m).
17. Label the intersection of arcs 16-17 and 18-19, point 20.
18. Draw line 7-21 through point 20. Note the azimuth of line 7-21 is 47°.6 (note 3).
19. Mark the intersection of line 7-21 and arc line 13-14 as point 22. Point 22 will be the center of the Ellipse.
20. Construct the Wright Square. Make each side of the Wright Square 925.5 feet (282.09 m) in length (note 4). The 925.5-foot length is related to the OCD in the following way. The diameter of the ideal Great Circle is equal to the hypotenuse of a right triangle whose sides are 1 OCD and ½ OCD, respectively. The diameter of the Great Circle therefore is 1,178.41 feet (359.18 m). From this it follows that the circumference of the Great Circle is 3,702.8 feet (1,128.61 m). If the Great Circle circumference is divided by 4, the result is 925.5 feet (282.09 m). Thus, the 925.5-foot (282.09 m) length is related to the OCD.
21. Position the center of the Wright Square on point 20. Orient the Wright Square so its northeast and southwest sides are perpendicular to line 7-21. Note the resulting azimuth of the west-east axis through the Square is 92°.6. This is to within 0°.2 of the 92°.8 azimuth for the Wright Square derived from Thomas’s (1894:466) survey data. (Since the cardinal direction of east extends at an azimuth of 90° and the spatial equinox occurred at an azimuth of 91°.3, the foregoing geometric design provides a better fit to the data than astronomical ones suggested elsewhere [e.g., Romain 2005a, 2005b].)
22. Draw a line from point 15 through point 22 to point 23.
23. Establish that the length of the long diagonal across the ideal Octagon from point 24 to point 25 is 1,733 feet (528.29 m). Draw line 26-27. Make line 26-27, 1,733 feet (528.29 m) in length. Position line 26-27 so it is bisected by point 22 and coincident with line 15-23.
24. Establish that the length of the major axis across the ideal Octagon from point 28 to point 8 is 1,490 feet (454.15 m). Draw line 29-30. Make line 29-30, 1,490 feet (454.15 m) in length. Position line 29-30 so it is bisected by point 22 and perpendicular to line 15-23.
25. Use points 26, 27, 29, and 30 to construct an ellipse.
26. From point 22 at the center of the Ellipse, draw an arc having a radius of 4 OCDs. Label this arc line 31-32.
27. From the east corner of the Wright Square at point 33, draw an arc having a radius of 4 OCDs. Label this arc line 34-35.
28. Label the intersection of arc lines 31-32 and 34-35, as point 36.
29. Construct the Salisbury Square. Make the two diagonals of the Salisbury Square each equal to 1 OCD in length. Orient the Square so one of its diagonals extends parallel to line 15-23.
30. Center the Salisbury Square on point 36.
31. The azimuth and location of the Great Hopewell Road are established in the following way. From the apex of Geller Hill (point 1 in figures 1 and 4), establish that the summer solstice sunset occurred at an azimuth of 300°.6 (A.D. 100, map-measured horizon elevation corrected for refraction and lower limb tangency = 1°.03). In figure 1, the summer solstice sunset azimuth is shown as line 1-37.
32. Draw line 1-8. Note that line 1-8 extends along an azimuth of 30°.7 and is perpendicular to the summer solstice sunset azimuth to within 0°.1.
33. From point 8, draw line 8-39 through point 38 on the Octagon. Make line 8-39, 2 OCDs in length.
34. From point 39, draw line 39-40 parallel to line 1-8. Make line 39-40, 12,672 feet (3,862.40 m) in length – equal to the distance to Ramp Creek. Note the azimuth of line 39-40 is 210°.7 (note 5).
35. From point 41, draw line 41-42 at an azimuth of 90°. Make line 41-42, 4 OCDs in length.
36. From point 43 on the Wright Square, draw line 43-44 at an azimuth of 300°.6 (note 6). Make line 43-44, 1 OCD in length.
37. Draw line 44-45. Make line 44-45, 2 OCDs in length at an azimuth of 295°.0 (equal to the azimuth given by Reynolds in Thomas 1894:467).
38. Draw line 45-46. Make line 45-46, 2 OCDs in length and at an azimuth that would connect to point 38 on the Octagon, if extended.
The design scenario outlined above may or may not have been used by the Hopewell. No doubt there are alternative geometric/astronomic protocols that will result in the same layout. The point is not that any one particular design strategy was used; but rather, that the complex was laid out according to an internally consistent logic based in the use of regular geometric shapes, astronomic alignments, and a basic unit of length.
It is instructive to compare the ideal geometric construction presented in figure 1 to what we find on the ground. For reasons that will become evident, this comparison requires two different illustrations. In the first comparative illustration – i.e., figure 2, the ideal geometric design presented in figure 1 has been superimposed over the USGS 7.5-minute series map for the Newark area. Notably, the USGS map shows the still extant Great Circle, Octagon and Observatory Circle earthworks. As can be seen, the correspondences between the ideal and actual are close.
In the case of the Ellipse, Wright Square, and Salisbury Square, since those earthworks are no longer visible on the ground, they are not shown on the USGS map. Accordingly, to compare the geometric ideal to what was once on the ground, we must rely on an alternative data source. In this case, the best alternative source is the Salisbury (1862) map. Unfortunately, certain aspects of the Salisbury map are not entirely accurate. As determined by reference to the USGS map for the area, for example, the distance that separates the center of the Observatory Circle from the center of the Great Circle is close to 6 OCDs. The Salisbury map shows this same distance as roughly 7 ½ OCDs.
Lesser distances shown by the Salisbury map, however, appear to be very accurate. The Salisbury map is very accurate, for example, with respect to the dimensions of the Great Circle, Wright Square, Octagon, and Observatory Circle. For analytical purposes therefore, it seems reasonable to presume that the dimensions for the Ellipse and Salisbury Square are equally accurate. Assuming this is the case, figure 3 shows the ideal geometric design superimposed over the relevant section of the Salisbury map. Again, the correspondences between the ideal and presumed actual are close.
Still, there are differences between the actual and ideal. The Great Circle earthwork, for example, is not a perfect circle. Its diameter varies between 1,163 feet and 1,189 feet, for an average of 1,176 feet (Thomas 1894:462). So too, the major axis of the actual Octagon and Observatory Circle extends along an azimuth of 51°.8, while the geometric ideal, based on the moon’s calculated azimuth is 52°.2, for a difference of 0°.4.
Several factors are likely responsible for the observed deviations including instrument inaccuracies and observation errors, to include daily changes in atmospheric refraction.
Construction errors are another source of error. Regardless of the methods used, there will always be some degree of error in the alignment of structures to their targets, as well as some margin of error in laying out multiples of any unit of length across long distances.
More significant are intentional deviations from the geometric ideal, in order to bring various features into alignment with celestial events. Certain of the Octagon’s walls, for example, appear to have been deviated from their geometric ideal in order to bring them into closer alignment to significant lunar events (Hively and Horn 1982:S12).
Adaptation to topographic constraints is another potential reason for deviation from the ideal. The location of the Salisbury Square per the Salisbury map, for example, is offset from the geometric ideal. In this case, positioning of the Salisbury Square according to the geometric ideal would have resulted in the earthwork being situated on a stream that feeds into the South Fork of the Licking River. In what may have been a workaround solution to this, the Square was positioned about 350 feet to the north of its ideal position, so its southwest side now borders the stream. Likewise, the walkway that extends between the Octagon and Wright Square may have been deviated from an ideal straight-line course, in order to avoid the small lake that once existed between the two earthworks. Similarly, the positioning of the Great Circle is deviated 1°.1 to the southeast from the geometric ideal (figure 1), perhaps to avoid its southwest side from being inundated by the same lake.
As to the Great Hopewell Road, according to Reeves’s (1936) aerial photos, the long straight section extends along an azimuth of 210°.5. The geometric ideal plotted in figure 1 extends along an azimuth of 210°.6. Thus the ideal differs from the actual by 0°.1. Of special interest is that the azimuth of the actual Road is not only parallel to a line extending from the apex of Geller Hill to the central Octagon vertex; the actual Road is also perpendicular to the summer solstice sunset azimuth of 300°.6, to within 0°.1.
By contrast, the winter solstice sunrise occurred at an azimuth of 122°.6 (map-measured horizon elevation as viewed from the apex of Geller Hill, corrected for refraction and lower limb tangency). Thus the perpendicular of the actual Road differs from the winter solstice sunrise azimuth by 2°.1.
Support for the notion that the Hopewell intentionally built the Road so it was perpendicular to the summer solstice azimuth comes from several observations. First, it is the case that walkways at other sites are oriented to solstice sunset azimuths – e.g., at Hopeton and Marietta (Romain 2000). At these sites the walkways point directly to the winter solstice sunset. Elsewhere, however, perpendicular relationships to the summer solstice sunset are found. At Fort Ancient, for example, the longitudinal axis of the site as drawn through Hopewell-established features, extends perpendicular to the summer solstice sunset (Romain 2004). At High Bank, the walkway leading from the earthwork also extends perpendicular to the summer solstice sunset.
Further, it appears that other walkways at Newark also bear a relationship to the sun. According to the Salisbury map, the walkway extending between the Octagon and Ellipse (figure 1, line 41-42) extends along an east-west azimuth - close to the spatial equinox rise and set azimuths. Also according to the Salisbury map, the walkway between the Octagon and Wright Square has a section (figure 1, line 43-44) that extends in alignment with the summer solstice sunset to within 0°.6. As explained in note 3, the walkway between the Wright Square and Ellipse appears related to the sun’s solstice positions.
Of considerable interest is that the Great Hopewell Road is not only perpendicular to the summer solstice sunset, it is also parallel to the Milky Way. As indicated, the Great Hopewell Road extends along an azimuth of 30°-210°. During Hopewell times, as twilight turned to darkness on the date of the summer solstice, the Milky Way would have become visible – as a band of stars, roughly 10° wide, extending from the northeast horizon at an azimuth of 30° at the constellation Cassiopeia, upward and across the sky through Cepheus, Cygnus, and Aquila, down through Scorpius, Lupus, and Centaurus on the southwest horizon, to an azimuth of about 210°. On the date of the summer solstice therefore, the Great Hopewell Road would mirror on earth the direction of the celestial Milky Way. Moreover, as they crossed, the Milky Way and summer solstice sunset azimuth would have effectively divided the Hopewell cosmos into quarters. These celestial azimuths would have crossed each other within 500 feet of Geller Hill – the earlier suggested axis mundi for the entire Newark complex (Romain 2005c).
Importantly, many Native American peoples – including the Apache (Curtis 1907:34), Pawnee (Von Del Chamberlain 1982:113), Cheyenne (Curtis 1911:158), Sioux (Powers 1975: 53, 93) and Shoshone (Mooney 1896:290) believed that the Milky Way was the path deceased souls traveled to reach the Otherworld. With reference to the Oglala Sioux, for example, Powers (1975:53) explains:
“The wanagi (ghosts) of humans and animals dwell on buttes in
the west. After one year they are fed for the last time and they
depart to the south along the wanagi tacanku ‘ghost road’, i.e.,
Milky Way. The aura of the Milky Way is caused by their campfires.”
If the Hopewell held similar beliefs (also see Lepper 1995:56), we can speculate that certain of the Hopewell deceased may have begun their journey at the crematory basins located within the terrestrial earthworks and from there, proceeded upward along the equinox and solstice sunset paths to the west, and finally, along the Great Hopewell Road/Milky Way Path to Ramp Creek - with its water barrier symbolism separating this world and the Otherworld.
An important question that arises in connection with the geometric model just presented relates to the matter of practicality. An argument could be made that because of the distances involved, the laying out of arc lines across the Newark plain that are 7 OCDs in length is impractical and for that reason, the model is flawed.
My response is that it would be a mistake to underestimate the capabilities of the Hopewell. As Clark (2004:208) points out: “...as scholars, most of us have severely underestimated the abilities and practices of Archaic peoples of the New World.” I think the same thing can be said with regard to Woodland peoples.
The matter also turns on the question of what is ‘practical.’ How ‘practical’ was it to build Monks Mound at Cahokia? How practical was it to build the Poverty Point earthwork? How practical was it to the Chaco Canyon complex? All these projects involved immense efforts.
Moreover, there are many reasons why people build structures that we might consider ‘impractical.’ Religious motivations, for example, often result in structures, such as the great cathedrals of Europe, or temples of India and Cambodia that might be considered ‘impractical.’ Nevertheless, such structures were built. When looking at prehistoric structures, we need to keep in mind that the notion of ‘practicality’ has Puritanical connotations and should not be used to judge the accomplishments or technical capabilities of non-Western peoples.
Having said that, I would suggest that it would not have been particularly difficult for the Hopewell to layout the Newark complex using geometric concepts and linear units of measure. Physical evidence suggests that at least part of the area occupied by the Newark complex was covered by prairie. Further studies may show that the entire Newark plain was a prairie island. If that was the case, then it would have been a relatively simple matter to clear the Newark plain, or sections that needed clearing, using fire. Using rods cut from saplings to a lesser multiple of the OCD, I estimate that a team of three people could layout a 7 OCD line in a single day. A team of 30 people could layout a 7 OCD arc in the same amount of time. A group of 100 people could layout and mark-off for later construction, the entire Newark complex in less than one week.
Other methods include the use of lengths of cord (Clark 2004:191), as well as improvised stadia-sighting techniques.
1. There are several high points or peaks on Geller Hill. In an earlier article (Romain 2005a), I showed the apex of Geller Hill to be at the northeastern-most peak. This assessment was based on analysis of the most accurate map known to me at the time - made by the City of Heath. Subsequent to the above analysis, I was able to obtain a more detailed, aerial photogrammetric map made by the Abrams Aerial Survey Corporation (1959) (figure 4). By reference to this more detailed map, it is found that the highest peak is not the northeastern-most peak; rather, the highest peak is the next one further south. This peak reaches an elevation of 916.7 feet and in figure 4, is identified as point 1. Point 1 is therefore considered the apex of the hill.
2. OCD is an acronym for Observatory Circle Diameter (Hively and Horn 1982:S8). Although the OCD unit of length derives its name from the Newark Observatory Circle, that should not be interpreted as meaning that the OCD unit necessarily originated at Newark. The term OCD is simply one of convenience. There is evidence that the OCD unit was used at other sites. Indeed, it may be that use of the OCD pre-dates the Observatory Circle and has its ultimate origins elsewhere.
3. According to the design offered here, the azimuth for line 7-20-21 is 47°.6. This angle may be related to the sun in the following way. For the period 100 B.C. to A.D. 100, the mean declination for the sun was 23°.68 (Ruggles 1999:57). This means that the angular separation between the summer solstice sun at noon (or meridian transit) and the winter solstice sun at noon (or meridian transit) was 47°.4. Accordingly, the difference between the azimuth of 47°.6 for line 7-20-21 and the solstice angle of 47°.4 is 0°.2. In this scenario, the walkway extending between the Wright Square and Ellipse may have been oriented so that it memorialized the angular separation between the noontime winter and summer solstices. Noon, or meridian transit conveniently marks the halfway point in a 24-hour day. Further, meridian transit of the sun on the date of the solstices provides an ideal marker for the exact beginning of the summer and winter seasons. In effect, the road or path between the Wright Square and Ellipse is thus balanced between the seasons.
4. For purposes of analysis, I drafted a plan of the Wright Square using Thomas’s (1894:466) distance and bearing data. As mentioned by Thomas, at the time of the survey, the south corner of the square had been already been obliterated. Thomas’s data for the remaining wall sections are as follows: station 1-2, 47°.27, 369.5 ft.; 2-3, 318°.12, 928 ft.; 3-6, 227°.78, 926 ft.; 6-7, 138°.22, 541 ft.; 7-1, 82°.78, 679 ft. These distances and azimuths were plotted using TurboCAD. Once the resulting geometric figure was constructed, I extended the incomplete wall sections thereby reconstructing the complete Square. Using the distance measure feature, the program returned linear values of 933.7 feet for wall 6-8 and 928.7 feet for wall 2-8. The mean value for the four walls therefore is: 928 ft. + 926 ft. + 933.7 ft. + 928.7 ft. = 929.1 ft. The mean length of 929.1 feet differs from the ideal length of 925 feet by less than one-half of one percent.
Thomas (1894:466) provides slightly different estimated lengths for the partially obliterated walls – i.e., 939 feet and 951 feet. Using these extrapolated lengths, the mean length for all four walls is 936 feet – which differs from the ideal length of 925.5 feet by 1.1 percent. Thus regardless of what method is used to estimate the length of the partially obliterated walls, the mean length of the Square’s four sides differs from the ideal by no more than roughly 1 percent.
5. The azimuth of 210°.5 for the Great Hopewell Road provided here differs from the azimuth of 206°.2, I suggested earlier (Romain 2005a). The 210°.5 figure is based on analysis of Reeves’s (1936) aerial photos, which show a long section of the Road where it crosses the Baltimore and Ohio Railroad tracks. At this point, the trajectory of the Road is 210°.5.
The earlier presented azimuth of 206°.2 represents an ideal, straight-line trajectory as plotted from the beginning of the Road immediately adjacent to the Small Circle next to the Octagon, to the near-terminus point of the Road located at the intersection of the Hopewell Road with a modern road, just south of the Newark-Heath airport.
The Road, however, is not entirely straight. Although the Road does indeed begin at the Small Circle, it extends southward for several hundred feet before turning to the southwest. Once the Road straightens-out, it then follows the 210°.5 azimuth.
Trajectory of the Road depends on which methodology is used – i.e., point-to-point; or alternatively, as measured using the longest straight section.
6. There is some question as to the azimuth of this walkway where it intersects the Wright Square. Azimuths derived from the Salisbury map vary in accuracy – ranging, for example, from 0°.2 for the major axis of the Octagon-Observatory Circle, to 3°.5 for the Great Hopewell Road. The Salisbury map shows the Wright Square walkway intersecting the Square at an azimuth of 300°.0. This would situate this section of the walkway to within 0°.6 of an alignment to the summer solstice sunset azimuth of 300°.6. Corroborating these data, Thomas (1894:466-467) reports that a survey made by Henry L. Reynolds found the following: “At station 39 a bend to S. 60° E. was made, which ran 730 feet to the middle of the northwestern entrance of the Square, the parallels reappearing here this entire distance.” The bearing that Reynolds provides equals a reciprocal azimuth of 300°.0 – which again, is to within 0°.6 of an alignment to the summer solstice sunset.
Contrary to this, Thomas’s (1894:Pl. XXXIV) drawing of the Wright Square, shows the same section of walkway extending along an azimuth of 306°.8 – which Hively and Horn (1982:S16, table II) propose as a lunar alignment to within 0°.9. Actual survey data provided by Thomas are generally accurate – i.e., to within ±0°.5 of their “true” value roughly 68% of the time and ±1°.0 of their “true” value 95% of the time (Romain 2004a:77-78). Drawings of the earthworks made by the draftsman Thomas engaged, however, are sometimes not accurate. In cases where survey data were not provided, Thomas’s draftsman apparently used estimated values. One example will suffice. With respect to the entranceway walls at High Bank, two different widths are shown for the distances between the walls (compare Thomas 1894:Pls. XXXVII and XXXVIII). As a result, the maps provided by Thomas cannot be relied upon. Several years ago, Robertson (1983:78-79) reached a similar conclusion: “…Table 2…indicates that maps produced directly from these accurate surveys (Thomas’s surveys) result in systematic errors in azimuths measured on the maps. These errors range from 0°.6 to -4°.0 in magnitude for the various sites….the maps published by…Thomas…are not sufficiently accurate to serve as the basis for quantitative archaeoastronomical investigations.”
The 306°.8 value used by Hively and Horn appears to have been derived by measuring off Thomas’s map of the Wright Square, rather than from actual survey data. The question is – which is correct – the Salisbury map azimuth and Reynolds’ survey data, or the Thomas map derived azimuth? While lunar azimuths appear incorporated in the Octagon, a solstice alignment of the Wright Square walkway would be consistent with the solstice-related alignment of the Great Hopewell Road.
I greatly appreciate the comments offered on earlier versions of this paper by Bradley T. Lepper and Robert Horn.
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