|Location:||Silver Bluff Audubon Sanctuary, Aiken County, SC, United States|
|Excavator(s):||Tammy Forehand, Mark Groover, students and volunteers|
|Dates excavated:||April-June 1999|
Situated on the east bank of the Savannah River, the Silver Bluff site is located in Aiken County, South Carolina, approximately 15 miles southeast of Augusta, Georgia. The site is part of a tract of land encompassing over 3,000 acres that was bequeathed to the National Audubon Society in 1975 by the estate of Floyd Starr. Established by George Galphin in the early 1740s, this backcountry trading post served the Native Americans and colonists in the area. By the 1770s, Galphin had greatly expanded his land holdings and turned his attention to operating a large-scale plantation, where enslaved laborers produced corn, indigo, and tobacco. Prior to the development of Galphin’s Trading Post, and his plantation, the area was home to a significant prehistoric occupation (Forehand et al., 2004: 51).
Archaeological investigations conducted between 1979 and 1999 explored components of Galphin’s trading post and plantation. Evidence suggests there were at least six buildings of interest in the area making up a well-defined, fortified compound. The buildings are thought to be quarters for the enslaved, a principal dwelling, outbuilding (perhaps a detached kitchen), two additional residential buildings, and a probable trading post store (Forehand et al., 2004: 51; Groover and Forehand, 1999:32). The 1999 investigation that comprises the assemblage in DAACS focused on the archaeological remains of a single large structure that was flanked by a palisade and may have been the principal dwelling at Silver Bluff.
The Silver Bluff site was investigated between November 1979 and March 1980 by the South Carolina Institute of Archaeology and Anthropology, the University of South Carolina, Aiken, and the Augusta Archaeological Society. This examination consisted of a systematic ground surface collection survey (Scurry et al., 1980:2). In 1996, the Savannah River Archaeological Research Program (SRARP), a division of the University of South Carolina’s South Carolina Institute of Archaeology and Anthropology (SCIAA), conducted a series of test pits and incorporated the use of ground penetrating radar in their research. In May and June of 1999, the SRARP, Augusta State University and the National Audubon Society’s Silver Bluff Plantation Sanctuary, joined forces to sponsor a archaeological field school at the site (Forehand et al., 2004: 58).
The 1999 field school investigation sampled two main areas using block excavation to focus on and around the remnants of a brick dwelling and related defensive palisade. In 2013, Dr. Charles Cobb and his graduate student at the University of South Carolina, joined the DAACS Research Consortium and chose to focus on the areas excavated during the 1999 field work. Joy analyzed the artifacts and field records from this season and and cataloged them into the DAACS database as part of the DRC’s Phase 1 pilot study. After the field school, further efforts to gather information about the site occurred in 2003 in the form of various remote sensing surveys, as well as a short summer camp co-sponsored by the SRARP and the Continuing Education Program at the University of South Carolina, Aiken (Forehand et al., 2004: 69).
Settlement in the Carolinas continued to expand westward during the eighteenth century. The British Colonial government developed an initiative to control the booming deerskin trade by setting up a series of trading posts along the frontier. Two of these were government run, but many more were privately owned. In addition to the goal of maintaining a trade monopoly with the Native Americans in the region, the enterprise was intended to maintain peaceful relationships between the native and colonial populations in the hope of encouraging new settlement in the area. As settlers moved into the area, the trade industry grew to accommodate their needs. A few trading posts became regional suppliers, one of which was located at Silver Bluff (mdgroover.iweb.bsu.edu).
Silver Bluff Plantation and Galphin’s Trading Post were owned and run by George Galphin, an immigrant from Northern Ireland. Galphin immigrated to the Carolina Colony in 1737 (Forehand et al., 2004:52). Soon after, Galphin joined Brown Rae and Company, a prominent trading company also known as the Augusta Company (Forehand et al., 2004: 53; Hamer 1982:43). He served as a native language interpreter for the government throughout the 1740s (Forehand et al, 2004:53; Hamer 1982:54). As Galphin traveled between the city of Charleston and the Carolina Backcountry to conduct business, he would have used a Creek trading path that ran along the bank of the Savannah River. Suitable land near Augusta struck his fancy, and he purchased a 400-acre tract there in 1744 (Forehand et al., 2004: 54; Hamer 1982:88-89). Galphin’s relationship with the government and native groups, along with the geographic proximity to the river and the ease of transport associated with it, enabled his trading post at Silver Bluff to flourish. This success enabled Galphin to establish his plantation where corn, indigo, and tobacco were produced. This endeavor necessitated a number of enslaved individuals. At the time of his death, Galphin owned 128 slaves and tens of thousands of acres of land in South Carolina and Georgia (Forehand et al., 2004:53-54).
Excavation History, Procedure, and Methods
The 1979-1980 investigation set out to identify all archaeological components present at the Silver Bluff site. The area was first mechanically disked, surveyed into 50-meter blocks, and then subdivided into 10-meter squares. Within a sample of these squares, a systematic collection of ground surface artifacts was undertaken to a depth of one to two inches (Scurry et al. 1980:2, 35-36).
The 1996 inquiry focused on a 100-x-100 meter grid that included the colonial period settlement area as indicated by the previous survey. Fieldwork consisted of an intensive surface collection of a 5-x-5 meter grid, as well as close-interval shovel testing, test unit excavations, and ground penetrating radar. Artifact spatial distribution analysis was conducted using the computer software called ArcView. Data suggested that there were six buildings in the area of interest making up a well-defined compound. The buildings are thought to be quarters for the enslaved, a principal dwelling, outbuilding (perhaps a detached kitchen), two additional residential buildings, and a probable trading post store (Forehand et al., 2004: 57-58; Groover and Forehand, 1999:32).
The 1999 investigation that comprises the assemblage in DAACS focused on the large, principal dwelling (shown on Figure 1 as Structure 2). An excavation block was opened up around a previously identified concentration of brick indicative of a chimney base. Ten of these excavation units make up part of the assemblage in DAACS. An additional area was investigated to the north of the excavation block that contains part of the same palisade trench. Test units were excavated in this area make up part of the DAACS assemblage. One goal of the field school was to obtain information about the methods used to construct the building (Groover and Forehand, 1999:32). Test units were dug in 10-centimeter levels and screened with ¼-inch mesh. Each unit contained three main levels. The features and postholes were located mainly beneath the lowest of these levels (Forehand, 2004).
Summary of Research and Analysis
The results of the 1999 investigation suggest that the large structure initially discovered in the 1996 survey was a half-timbered earthfast building with brick-filled walls and a brick chimney. This construction method is unique for the period in the Carolina Backcountry. Few buildings of this period have been studied; however, those that have seem to have been clad in clapboard or were constructed of woven wattle walls plastered with daub (Groover and Forehand, 1999:31). The density of brick debris in conjunction with a row of postholes supports the idea of a brick structure. Moreover, Galphin’s will makes mention of two brick buildings located on the property. He discusses an “old Brick House” and a “new Brick House” (Forehand et al., 2004:59; Will of George Galphin, 1776:Box 40 Pack 898). The building remains uncovered during the 1999 excavation are likely the “old Brick House,” Galphin’s first dwelling constructed near his trading post (Forehand et al., 2004:60).
In addition to the building, a defensive palisade was discovered. This feature consisted of a trench containing intermittently spaced buttress posts that likely supported horizontal spanners (Groover and Forehand, 1999:32). The archaeological data uncovered suggests that Galphin’s dwelling and the palisade were built simultaneously. Brick debris associated with the construction of the house was placed in the palisade postholes, and the upper portion of the palisade trench was filled with refuse after the posts had been seated and partially backfilled. Over time, refuse accumulated forming a midden (Forehand et al., 2004:62).
Further efforts are required to determine the exact boundaries of the palisade and greater complex, as well as the function, size, and construction methods for the remaining five structures located on the site (Forehand et al., 2004:71).
As of March 2015, approximately half of the 1999 material assemblage has been entered into DAACS. These contexts include a chimney, a number of postholes and postmolds, and portions of a trench (palisade). Stratigraphic relationships have been established among the entered contexts and are accessible throughout these pages. Peripheral areas remain to be cataloged and will be entered into DAACS during the summer of 2015.
University of South Carolina
General Site Information:
- In the DAACS database, the Silver Bluff site is designated as Project “1306”. Artifact ID numbers for artifacts associated with the site therefore begin with the 1306 prefix.
- The information contained in the database is from the 1999 archaeological field school hosted by Augusta State University, the Savannah River Archaeological Research Program/South Carolina Institute of Archaeology and Anthropology, and the National Audubon Society’s Silver Bluff Plantation Sanctuary. The sample contains 18 units selected to comprise the DAACS Research Consortium pilot study site. The contexts include an architectural feature (chimney), a number of postholes and postmolds, and portions of a trench (palisade).
- Over 32,000 artifacts have been entered for 18 units in and around the the primary dwelling structure and associated palisade at the Silver Bluff site. These quadrats/units include 320-336 and quadrat 341. In addition, Features 18-26 have been cataloged.
- Stratigraphic relationships have been established among the entered contexts and are accessible through the Harris Matrix and Context Queries in the Query the Database section of the website. Additional areas remain to be cataloged and will be entered into DAACS in the near future.
- The sample in DAACS and the remaining peripheral areas comprise 284 square meters centered on the primary dwelling and palisade.
- These areas were targeted based on work that occurred in 1979-1980 and 1996; however, these excavations are not directly included in DAACS.
- Units were laid out on North-South transects, then numbered.
- Shovels and trowels were used for excavation.
- General level sediment was screened through ¼-inch hardware cloth.
- Feature sediment was typically water screened through 1/8-inch hardware cloth, though sometimes floated and sometimes dry screened. This information is recorded as the Recovery Method for each context sample.
- Measurements are in meters and centimeters.
- Levels were excavated in arbitrary 10-centimeter increments and were labeled with descending letters.
- Soils are equivalent by level site-wide. Levels A and B are plowzone.
- Artifacts recovered from level and wall scrapings are cataloged without a level affiliation (for example, 1306-327-DRS), but in some cases required differentiation by area (1306-323-WEST). This was done to maintain divisions that were established in the field.
- Feature contexts have been entered with regard to unit and level, though most features were evident only at level C and below. Feature contexts (such as F18) contain data from one unit in which that feature was present, the remainder of the data can be found in contexts that specify both unit and feature (such as 320-C-F18). Again, this was done to preserve established divisions.
- The collection was previously analyzed and curated by the Savannah River Archaeological Research Program.
- Dr. Charles Cobb is a partner in the DAACS Research Consortium (DRC), an Andrew W. Mellon-funded initiative that facilitates collaborative scholarship in the humanities and social sciences, especially in archaeology, across institutional and spatial boundaries.
- Brandy Joy, a graduate student at the University of South Carolina, was Dr. Cobb’s research assistant during the two-year DRC project. Joy cataloged the artifacts and associated context records from the 1999 field school excavation conducted at the Silver Bluff site.
Descriptions of Architectural Materials at the Site:
Brick (cataloged as “Brick, fragment” and “Brick/Daub” according to DAACS protocols defined in the General Artifacts Cataloging Manual) at Silver Bluff is observed to be typically orange and occasionally red in color, crumbly, and uniformly clay in composition.
Mortar (cataloged as “Mortar” according to the DAACS protocols defined in the General Artifacts Cataloging Manual): two types are observed at Silver Bluff: one (typical) type is whitish to grayish in color and composed of lime with crushed shell. A second (atypical) type is orange in color with a lime-based matrix and contains numerous shell fragments from minute (crushed) to approximately 15 mm in size. This type is found attached to plaster as well as separate from other materials. Two fragments have flattened sides indicating either a smoothed finish or contact with brick or other object. However, there are no observed cases of this material attached to brick, typical mortar, or any other object. Catalog entries of this material are described in the notes section.
Plaster (cataloged as “Plaster” according to the DAACS protocols defined in the General Artifacts Cataloging Manual) at Silver Bluff is observed to be similar to mortar at the site, has a smooth finish, and is white in color.
Feature 19 (Palisade Trench) Context Naming Conventions:
In some units, particularly after initial discovery, Feature 19 was bisected and dug in 5cm levels. This is reflected in the naming convention of these contexts, e.g. 1306-327-CF19W1. This convention indicates the entry consists of Feature 19’s western, uppermost 5-cm level within Quadrat/Unit 327. The second level of that same feature, in that same unit is 1306-327-CF19W2, etc. In some cases, there were separations based on natural soil delineations. In these instances the context is split. For example: 1306-327-CF19W1B is the mottled part of the feature that is otherwise composed of solid, dark colored soil. Likewise, cleaning and photo preparation have been entered into their own contexts and the context names reflect this with suffixes such as WC for wall clean or FLOOR for floor clean. Although standardization was attempted, character limits in the database for context titles sometimes affected uniformity. However, in each case, data entry notes exist in the context records and explain the particulars.
The original excavators of the Silver Bluff site assigned numbers to individual features, and these numbers have been carried into DAACS. Original feature numbers have been provided an F-prefix, which precedes the number (i.e., F18 equals Feature 18).
Excavated contexts that belong to the same depositional basin (e.g., a posthole and postmold or the layers in a single pit) have been assigned a single feature number. In addition, single contexts have been given feature numbers when the original field records indicate that the excavators recognized a context’s spatial distinctiveness from surrounding contexts.
Feature groups are sets of features whose spatial arrangements indicate they were part of a single structure (e.g., structural postholes, subfloor pits, hearth, or palisade) or landscape element (e.g. postholes that comprise a fencerow). Feature Groups assigned by DAACS have an FG-prefix, which precedes the number (i.e., FG01 equals Feature Group 1).
|F19||Trench, fence||323-C, 325-C-F19, 327-C-F19, 332-C, F19|
|F18||Chimney Base||320-C-F18, 321-C-F18, 324-C-F18, 328-C-F18, 329-C-F18, F18|
DAACS Seriation Method
DAACS staff aim to produce a seriation-based chronology for each site using the same methods (see Neiman, Galle, and Wheeler 2003 for technical details). The use of common methods for all sites in the archive is designed to increase comparability among temporal phases at different sites. The methods they produced are summarized below. Archive users may also use the Mean Ceramic Date queries provided on the Query the Database section of this website to calculate MCDs for individual contexts or features.
Only assemblages from features or stratigraphic groups with more than five ceramic sherds are included in these ceramic-based seriations. DAACS has currently been unable to produce a statistically significant seriation-based chronology for the Silver Bluff site; however, the site-wide Mean Ceramic Date and the BLUE MCD, which gives less influence to ceramic types with long manufacturing spans, point to the occupation’s temporal placement as the second quarter of the eighteenth century. Two other measures that are less sensitive to excavation errors and taphonomic processes that might introduce a small amount of anomalously late material into an assemblage were used. They are TPQp90 and TPQp95. The TPQp95 of 1762 provides a robust estimate of the site’s TPQ based on the 95th percentile of the beginning manufacturing dates for all the artifacts comprising the assemblage. The TPQp90 of 1720 provides a more robust estimate of the site’s TPQ based on the 90th percentile of the beginning manufacturing dates for all the artifacts comprising the assemblage.
Artifact data from additional excavation units at Silver Bluff are still being entered into DAACS. Once the data entry has been completed, DAACS staff will attempt to phase the site once again using seriation-based correspondence analysis.
Silver Bluff Mean Ceramic Dates and TPQs
Silver Bluff Harris Matrix
The Harris Matrix summarizes stratigraphic relationships among excavated contexts and groups of contexts that DAACS staff have identified as part of the same stratigraphic group. Stratigraphic groups and contexts are represented as boxes. Lines that connect these boxes represent temporal relationships implied by the site’s stratification, as recorded by the site’s excavators (Harris 1979).
Stratigraphic groups representing multiple contexts are identified on the diagram by their numeric designations (e.g., SG01) followed by the feature number. Contexts that could not be assigned to stratigraphic groups are identified by their individual context numbers (e.g., 321-C). Contexts and stratigraphic groups that are associated with features are identified on the diagram by the stratigraphic group, followed by the feature number (e.g., SG01: F18).
This Harris Matrix is based on data regarding stratigraphic relationships recorded among contexts in the DAACS database and was drawn with the ArchEd application. See http://www.ads.tuwien.ac.at/arched/index.html.
See Silver Bluff Chronology for stratigraphic and phase information.
For a printable version, download the Harris Matrix [PDF].
CAD site plan in DXF format, compiled by DAACS.
Forehand, Tammy R., Mark Groover , David C. Crass , and Robert Moon
2004. Bridging the Gap Between Archaeologists and the Public: Excavations at Silver Bluff Plantation, the George Galphin Site, Early Georgia 32:51-73.
Forehand, Tammy R., and Mark Groover
1999 SRARP Field School at Galphin’s Trading Post on Silver Bluff Plantation., Legacy 4:32-33.
Forehand, Tammy R.
2004 Archaeological Field Records for Silver Bluff On file at the Savannah River Archaeological Research Program, New Ellenton, South Carolina.
Hamer, Friedrich Peter
1982 Indian Traders, Land and Power: Comparative Study of George Galphin on the Southern Frontier and Three Northern Traders M.A. Thesis, Department of History, University of South Carolina, Columbia.
Neiman, Fraser D., Jillian E. Galle , and Derek Wheeler
2003 Chronological Inference and DAACS. Unpublished paper presented at the annual meeting of the Society for Historical Archaeology, Providence, Rhode Island. On file at the Department of Archaeology, Thomas Jefferson Foundation, Charlottesville, Virginia.
Ramenofsky, Ann , Fraser D. Neiman , and Christopher Pierce
2009 Measuring Time, Population, And Residential Mobility From The Surface at San Marcos Pueblo, North Central New Mexico. American Antiquity, 74(3): 505-530.
Scurry, James D., J. Walter Joseph , and Fritz Hammer
1980 Initial Archaeological Investigations at Silver Bluff Plantation Aiken County, South Carolina. SCIAA Research Manuscript Series 168, Institute of Archaeology and Anthropology, University of South Carolina, Columbia.
Abbeville County Registry of Probate
1776 Will of George Galphin, Box 40 Pack 898. Abbeville, South Carolina.