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Hopewell
Archeology:
The Newsletter
of Hopewell Archeology in the Ohio River Valley
Volume 7, Number 1, December 2006
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1. Excavation of the East Embankment Wall,
Hopewell Mound Group: A Preliminary Report By Mark J.
Lynott
There are many famous and well known earthen enclosure
sites in southern Ohio, but none has greater name recognition
than the Hopewell site itself. With at least 40 mounds,
the site is impressive enough, but the presence of more
than 4 km of earth and stone embankment walls forming
one large enclosure and several smaller ones makes this
site clearly worthy of being the type site for this
famous epoch in the archaeological record. The site
has been greatly modified by nearly two hundred years
of cultivation and three major archaeological excavations,
but much of the site still has the potential for productive
research. This paper summarizes a recent excavation
aimed at recording the materials and construction methods
of the eastern wall of the main enclosure. Although
the embankment walls at the Hopewell Mound Group have
fascinated archaeologists for nearly two centuries,
this is only the second attempt to document the nature
of the earthen wall and ditch.
The first description of the Hopewell Mound Group
was provided by Caleb Atwater (1820), who estimated
the area within the large enclosure at 110 acres. Atwater
observed that it is ”generally twelve feet from
the bottom to the summit of the wall, which is of earth.
The ditch is about twenty feet wide, and the base of
the wall the same. There is no ditch on the side next
the river. The small work, on the east side, contains
sixteen acres, and the walls are like those of the larger
work, but there is no ditch. The largest circular work,
which consists of a wall and ditch like those already
described, is a sacred enclosure, including within it
six mounds, which have been used as cemeteries”
(Atwater 1820: 183).
Squier and Davis (1848) described the main enclosure
as a parallelogram, 2800 feet by 1800 feet with one
rounded corner. They note that the wall along the creek
follows the edge of the bank, and contains a lot of
water rounded cobbles. The wall along the creek was
4 ft. high in 1846. The north and east walls are 6 feet
high and 35 ft. wide at base with an exterior ditch
of similar dimensions.
| W.K. Moorehead (1922) conducted excavations
at the Hopewell Mound Group in 1891 and 1892 for
the World’s Columbian Exposition and produced
some of the earliest photographs of the site, including
this image (Figure 1) of the field
camp adjacent to the embankment wall and ditch.
Moorehead’s report was not published until
1922, and his published map and description of the
mound group rely heavily on the description provided
by Squier and Davis (1848). |
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on image to enlarge |
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Figure 1. View of Moorehead’s
field camp and the main embankment wall and ditch
in 1891 or 1892. (Moorehead
1922, plate 38) |
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H.C. Shetrone conducted additional excavations
for the Ohio Archaeological and Historical Society
from 1922 though 1925. Shetrone described changes
in the site since Moorehead’s research,
and also discrepancies between what he observed
and what previous researchers had reported. Shetrone
took note that at the Turner Works near Cincinnati,
F.W. Putnam found burials and other features had
been incorporated into and under the earthen embankment
walls. In addition to excavating mounds, Shetrone
conducted exploratory excavations in the walls
at the Hopewell Mound Group to determine if similar
materials might be present.
Shetrone excavated 200 ft. of the east wall of
the main enclosure. He reported that “Upon
the original surface were found several unimportant
and not well defined fire-beds, which apparently
were only incidental to occupation previous to
the erection of the wall. Tests at other points
revealed nothing” (Shetrone 1926: 112).
After nearly two centuries of cultivation, only
the walls of the main enclosure are still visible.
Fortunately, geophysical survey has proven to
be an effective tool for relocating and mapping
earthen walls in this region (Lynott and Weymouth
2002). In 2004, Arlo McKee (2005) conducted a
detailed geophysical survey of the area surrounding
Mound #23 and the main embankment wall east of
Mound #23.
| McKee
surveyed an area 120 m by 60 m with a G858
cesium magnetometer, EM-38 conductivity meter,
and RM-15 resistance meter.His data show that
although Mound #23 had been thoroughly excavated,
the floor at the base of the mound is readily
visible (Figure 2). |
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on image to enlarge |
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Figure 2. Magnetic
map of area surrounding Mound 23 from McKee
2005. |
The geophysical data also
clearly shows the embankment wall and associated
ditch. His study is one of several recent
studies of Hopewell earthen enclosure sites
in the Scioto Valley which demonstrate that
geophysical survey can be an effective tool
for relocating earthen architectural features.
In June 2006, the Midwest Archeological
Center excavated a trench across the eastern
embankment wall of the main enclosure. The
location for the trench was selected after
reviewing the geophysical data collected
by McKee in 2004. This data indicated that
at least part of the earthen wall was intact
in this area. An east-west transect across
the embankment wall, which runs roughly
north-south at this location, was chosen.
With assistance from Jennifer Pederson and
Kathy Brady-Rawlins, wooden stakes were
set to identify the corners for a trench
that was potentially 60 m long and 2 m wide.
The
width of the trench was excavated
as planned, but the length of the
trench was reduced to focus our efforts
on what remains of the embankment
wall and exterior ditch. Consequently,
the trench that was actually excavated
was 44 m long and 2 m wide. Excavations
were done largely with a backhoe (Figure
3).
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on image to enlarge |
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Figure
3. Backhoe excavation of Trench
06-1, June 2006 (photo by Jeanna Boyett).
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on image to enlarge |
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Several small areas of charcoal or
discolored soil were identified and
left in place for hand excavation
(Figure 4). Most
of these were later determined to
be products of bioturbation, and the
two that were probably cultural features
do not appear to be related to wall
construction activities. One post
hole in the wall fill was observed
and recorded but it appears to predate
the deposition of soils that were
used to form the embankment wall.
The north wall of the trench was
used to record the soil layers present
in the trench, and clearly shows that
all of the A horizon and likely much
of the B horizon were removed from
this area prior to the start of wall
construction (Figure 5).
This practice would appear to be fairly
common in the construction of earthen
enclosures in the Scioto River valley,
and is well documented from our work
at the Hopeton Earthworks (Lynott
et al. 2005). |
Figure 4. Hand
excavation of Trench 06-1, June 2006.
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click
on image to enlarge |
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Figure 5. North
wall of Trench 06-1 showing basal remnant
of the East Embankment wall.
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Unfortunately, agricultural activities
have severely truncated the wall, so the
observations presented here are based totally
on the basal remnants of the earthen wall.
The primary intact material forming the
core of the wall is a yellow-brown loam.
This rests on the truncated subsoil and
itself has been truncated at the top by
plowing. Consequently, it is impossible
to determine if this formed the bulk of
the wall fill or just the foundation. At
the western end of the wall fill, there
is a small area of intact wall fill that
is comprised of red-brown silt loam with
lots of gravel. This layer is quite distinct
from the yellow brown wall fill, and the
sharp boundary between the two is consistent
with the methods of construction that have
been recorded in other Scioto River valley
embankment walls. We cannot determine if
this small remnant of red soil once formed
a larger deposit that covered the interior
of the embankment wall surface, but this
would be consistent with construction approaches
at other earthen enclosures in this region.
The western margin of the wall is visible
at E4863 as an organic dark gray loam with
gravel that is probably a soil that formed
on the wall surface and was subsequently
covered by wall fill after cultivation was
initiated in the nineteenth century. This
soil layer rises from west to east and is
truncated by the plowzone. A corresponding
layer on the eastern side of the wall would
have merged with the exterior ditch at about
E4874, but evidence of it has been destroyed
by cultivation.
| The exterior
ditch is visible from about E4873.5
to E4878.5. The ditch was excavated
down into the loose sand and gravel
subsoil on the exterior or east side
of the embankment wall (Figure
6). The close proximity to
the embankment wall indicates they were
likely built at the same time. The sand
and gravel subsoil into which the ditch
excavated is very loose and unconsolidated.
To prevent this material from slumping
into the ditch, the builders of this
feature lined the ditch surface with
a brown clay loam. |
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on image to enlarge |
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Figure 6. North
wall of Trench 06-1 showing Rolfe Mandel
and Arlo McKee examining the external
ditch in profile. |
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This was a very tight and stable surface.
A dark organic gray loam with charcoal
was found on top of the ditch lining.
This is a re-deposited layer that
likely formed from materials that
washed into the ditch after the wall
and ditch were built. Soil materials
in the ditch above this layer are
also re-deposited, possibly after
the start of cultivation in the nineteenth
century.
The great earthen walls that form
the enclosures at the Hopewell Mound
Group have attracted scientific attention
for nearly two hundred years. In 1925,
H.C. Shetrone of the Ohio Archaeological
and Historical Society excavated 200
feet of the eastern wall of the main
enclosure. Shetrone had hoped to discover
burials and other features within
the fill of the wall. Although he
did find features under the earthen
wall, they were uninteresting in comparison
to the mortuary features he unearthed
under the mounds. Shetrone devoted
only a few lines in his 1926 report
to this wall excavation, and observes
that the wall was built with fill
from the adjacent ditch.
Years of cultivation have reduced
most of the embankment walls at the
Hopewell Mound Group to the point
where they are barely discernable.
Geophysical evidence suggested that
at least the base of the wall was
preserved in the area near Mound #23,
and the test trench excavated in 2006
demonstrated that this is indeed the
case. Unfortunately, only the very
bottom of the original wall remains
undisturbed, but this enough to provide
us with some insights into how this
portion of the wall was constructed.
| The
absence of an A horizon under
the wall suggests that the top
soil from this area was removed
before the wall was built (Figure
7). It would seem likely
that much of this topsoil was
quarried and used in construction
of the many mounds at this site.
Whether topsoil was quarried across
the entire surface of the site
is unknown at this time, but it
would seem likely that exposing
the subsoil was part of the architectural
ritual. |
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click
on image to enlarge |
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Figure
7. Drawing of north wall of Trench
06-1, and hypothetical reconstruction
of original wall strata. |
| The wall remnant
is comprised of two different
soils. A yellow-brown loam and
a red-brown silt loam with lots
of gravel. These two soils do
not appear to have been randomly
piled together to form the wall,
but were kept separate and unmixed.
The fill at the base of the mound
is definitely not the sand and
gravel subsoil material that was
quarried from the adjacent ditch.
The red-brown silt loam is not
present near the ditch and must
have been quarried somewhere else
nearby. The ditch was dug into
loose and unconsolidated sand
and gravel subsoil, and the builders
lined the ditch with a clay loam
to stabilize it. The clay loam
also had to have been quarried
from somewhere else and brought
to this location.
The clay lined ditch is very similar
to the ditch recorded by Frank
Cowan at the Shriver Circle near
Mound City Group (Cowan, Picklesimer
and Burks 2006). Cowan believes
the clay lining at Shriver was
intended to hold water in the
ditch, and this may also be the
case at the Hopewell site. While
analysis is ongoing, the rich
soil that formed in the bottom
of the ditch may reflect a moist
environment. Squier and Davis
(1848) speculated that the builders
of the earthen walls may have
re-directed the flow a stream
channel to flow in the ditch of
the west wall of the main enclosure.
Small springs were present at
the base of the hill on the north
side of the main enclosure in
1848, and one of these may have
been directed to flow in the ditch
along the east wall of the main
enclosure.
Hopewell earthen enclosures in
southern Ohio exhibit many different
shapes and the walls vary in size
and configuration. Early scholars
assumed that walls which were
built in association with ditches
were built from soil quarried
from the ditch. This was likely
the case at some sites, but not
at the Hopewell Mound Group. While
it is likely that the ditch fill
was used to build parts of the
wall, materials used in the walls
appear to have been carefully
sorted and not mixed together.
The absence of any dateable
features associated with wall
construction makes it impossible
to determine the absolute age
of the embankment wall and ditch.
However, it is notable that
the removal of the A horizon
preceded wall construction at
least in the area around Mound
#23. If this observation holds
true for the entire embankment
wall, it is likely that the
missing A horizon was used in
construction of some or all
of the mounds at this site.
If that is the case, then the
embankment wall and ditch were
likely built after mound building
was well established at this
site. Further research on the
embankment walls is clearly
needed to determine if the evidence
recorded in our 2006 trench
is typical of the rest of the
site.
References Cited:
Atwater, Caleb
1820 Description of Antiquities
Discovered in the State of Ohio
and Other Western States. Reprinted
by AMS Press, Inc. for the Peabody
Museum of Archaeology and Ethnology,
Harvard University, Cambridge,
Massachusetts, 1973.
Cowan, Frank L., John W. Picklesimer
II, and Jarrod Burks
2006 The Shriver Circle Earthwork
160 Years After Squier and Davis.
Paper presented at the 52 Annual
Meeting of the Midwest Archaeological
Conference, Urbana, Illinois,
October 14, 2006.
Lynott, Mark and John Weymouth
2002 Preliminary Report, 2001
Investigations, Hopeton Earthworks.
Hopewell Archaeology, 5:1: 1-7.
Lynott, Mark, John Weymouth,
Rolfe Mandel, Rinita Dalan,
and Bruce Bevan
2005 Ohio Hopewell Earthen Wall
Construction: A View from the
Hopeton Earthworks. Paper presented
at the 70th Annual Meeting of
the Society for American Archaeology,
Salt Lake City, Utah.
Warren K. Moorehead
1922 The Hopewell Mound Group
of Ohio. Field Museum of Natural
History, Publication 211, Anthropological
Series, Vol. VI, No. 5, Chicago.
McKee, Arlo
2005 Geophysical Investigations
of the Hopewell Earthworks (33Ro27),
Ross County, Ohio. Hopewell
Archeology 6:2:4.
Shetrone, Henry C.
1926 Exploration of the Hopewell
Group of Prehistoric Earthworks.
Ohio Archaeological and Historical
Quarterly 35: 1-227.
Squier, E.G. and E.H. Davis
1848 Ancient Monuments of the
Mississippi Valley. Smithsonian
Contributions to Knowledge,
Vol. 1, Smithsonian Institution,
Washington, D.C.
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