A CHANGING LANDSCAPE
Chapter Three (Part A)
used three survey techniques to locate prehistoric and historic resources
at Sudley Post Office: 1) shovel test pits (stps), 2) metal detector
sweeps, and 3) ground penetrating radar (GPR).
Each of these survey techniques allowed for the identification of
several cultural resources at Sudley Post Office.
The use of these techniques with each other allows for a more
in-depth evaluation and identification of resources present on the
following discussion summarizes each of the survey techniques used at
Sudley Post Office and then provides a synchretic overview of the results.
SHOVEL TEST PIT SURVEY
Excavation of stps at the Sudley Post Office allowed for the location of peripheral structures, historic middens, and prehistoric deposits. The identification of cultural features outside the area immediately around the structure allowed for a better understanding of the occupants' use of the landscape. Along with historic features, stps permitted the identification of a scatter of prehistoric lithics at Sudley Post Office. In his survey of Manassas Battlefield Park, McGarry (1986) located numerous prehistoric sites along the bluffs of Bull Run (McGarry 1986). The geographic location of Sudley Post Office suggested the high probability of locating prehistoric deposits at the site. Stps remain the most viable method for finding prehistoric resources in areas with poor ground visibility such as Sudley Post Office. Excavation of 2.5 ft x 2.5 ft and 5 ft x 5 ft excavation units, as described in Chapter 4, allowed for further examination of historic and prehistoric artifact concentrations located through stp survey.
Crew members laid out stps on a 25 ft interval grid using a transit and pull tape. The structure for Sudley Post Office served as the axis for this grid (Figure 3.1). The area tested by stp survey measures 450 ft north-south by 125 ft east-west. Stps were limited to the ridge where Sudley Post Office sits and were not placed on slopes greater than 20%. Each stp was excavated the width of a shovel blade at least .3 ft into sterile soil. All soil was screened through 1/4 inch hardware cloth and all cultural material was retained. Ninety-nine stps were excavated.
Excavation of stps identified three historic artifact concentrations adjacent to Sudley Post Office and a prehistoric scatter 200 ft south-southwest of Sudley Post Office.
Excavation of nine stps in the area of N425E200 located a concentration of prehistoric materials (Concentration P1). The concentration measures 75 ft north-south by 50 ft east-west (Figure 3.2). Stps excavated in this area recovered 17 prehistoric materials including two quartz Halifax Points, a Savannah River blade fragment, eight quartz shatter, five flakes (two rhyolite and three greenstone), and a quartz chunk. Diagnostic points recovered from stps at the site date to the Late Archaic period.
A smaller concentration of prehistoric materials is 100 ft to the south of the Sudley Post Office structure in the area of N575E300 (Concentration P2). The materials in this area were widely spaced between three stps (N550E250, N575E300 and N575E325) and covered an area of 75 ft southwest-northeast by 30 ft northwest by southeast. Excavation of stps recovered two quartz shatters, two quartzite shatters, and a quartzite flake.
McGarry located prehistoric encampments in similar geographic settings to Sudley Post Office (McGarry 1986). Sites surveyed by McGarry lie on the high bluffs overlooking Bull Run to the southeast of Sudley Post Office. McGarry did not survey areas along the eastern flood plain of Bull Run since this property was outside National Park Service boundaries. Most of the sites along the bluffs were of Middle to Late Archaic occupation.
Thirty-seven of the 99 stps excavated at Sudley Post Office contained historic deposits. Half the stps (19, n=51%) containing historic deposits were within 100 ft of the structure. However, 15 of the stps within 100 ft of the structure contained more than two artifacts. In comparison, only eight of the stps outside the 100 ft perimeter of the structure contained more than two artifacts. As indicated by the trend surface map in Figure 3.3, most of the artifact concentrations were next to the structure with outlying areas only having a thin scatter of materials.
Most of the stps at a distance greater than 100 ft from the house were to the south of the structure. Stps excavated in this portion of the site contained mostly unidentifiable bottle glass (n=18, 58%) and nails (n=7, 24%). Two areas contained a sightly higher concentration of these materials. The first was located next to the driveway near N525E225 (Concentration H1), and three stps (N550E200, N525E225, and N550E250) in this area contained nine bottle glass fragments and sherd of window glass. The second concentration was at stp N450E200 (Concentration H2). Four stps (N400E225, N425E225, N425E200, and N450E200) in this area contained two bottle glass fragments, an olive green wine bottle fragment, and four nails.
The overwhelming concentration of historic materials was found next to the structure. Excavation of stps located three potential midden deposits surrounding the structure of Sudley Post Office to the east, southwest, and south. All three of these artifact concentrations were in areas with a gradient greater than 10%.
The midden deposit with the highest density of material was located 25 ft to the east of the structure (Concentration H3). Stp N700E350 contained more than 60 historic artifacts, most dating to the late nineteenth/early twentieth century. Artifacts recovered from this stp include two whiteware plate fragments, six bottle glass fragments, 31 fragments of stained window glass, eleven fragments of window glass, a shell button, seven wire nails, and a blob of lead solder. Most of this artifact concentration is downslope to the east of N700E350. Excavation units placed in this concentration revealed a heavy concentration of objects dating to the Davis occupation of the site.
Stps revealed a second concentration 30 ft to the southwest of the structure (Concentration H4). This deposit is on a heavily vegetated slope facing the level area below and west of the structure. The total number of artifacts recovered from Stp N640E265 was 15. The deposit contained an Indian Head Penny dating to 1891 along with machine-cut nails and bottle glass.
The third concentration is 50 ft to the south and downslope of the structure (Concentration H5). Excavation of stp N625E325 recovered twenty-seven artifacts including three green-glazed whitewares, 14 nails (twelve machine cut and two unidentified), two bottle glass fragments, three clothing clasps, a bone, and a wood screw.
Excavation of stps at Sudley Post office allowed for the identification of a prehistoric scatter (17 lithics from nine stps), a light prehistoric scatter (five lithics from three stps), three historic sheet midden deposits (average of 36 artifacts per stp), and two low density scatters of historic materials (average of four artifacts per stp). The prehistoric scatters are to the south of the Sudley Post Office structure with the heaviest concentration being the southernmost. The three historic middens are to the east, southwest, and south of the structure. The eastern historic midden contains the heaviest concentration of materials and dates to the late nineteenth/early twentieth century. The two low-density historic scatters are south of the structure.
METAL DETECTOR SURVEY
In September 1997, a controlled metal detector survey was used to examine the landscape at Sudley Post Office for historic artifact concentrations. Metal detectors are advantageous for finding minute artifact clusters that might fall between stp transects. Studies conducted at Antietam Battlefield, Maryland, have located hundreds of militaria in areas that stp survey revealed no historic materials (Stephen Potter 1997, personal communication). Metal detector surveys of Brawner Farm and Robinson House at Manassas National Battlefield have located structures, battlelines, and concentrations of militaria (Parker 1986, Parsons et al. in prep). Similarly, metal detecting was conducted at Sudley Post Office in hopes of finding outbuildings and militaria. The systematic metal detector survey conducted at Sudley Post Office revealed several scatters of historic material across the landscape and the location of John Thornberry's wheelwright shop.
Robert Marcus and William Leigh, III, conducted the metal detector survey at Sudley Post Office. Bob Marcus used a White Spectrum 6000 machine with a 9" coil. William Leigh III used a White 2000 with a 8" diameter head. Prior to the systematic survey, machine operators swept the area to determine the amount of scattered metal debris and to calibrate their machines. Areas swept by the metal detectors were the mown grass areas surrounding the structure and some limited testing was conducted in wooded sections.
The survey used the stp grid to coordinate metal detector sweeps. When machine operators encountered a hit, they placed a plastic flag to mark the location. In most areas, the density of metal detector hits was low enough to allow the operator to excavate each hit with a small shovel or knife. The operator removed soil, swept the hit again to more closely locate the object and continued to remove soil and sweep the hit until the object was located. Once excavated, the machine operator labeled the flag with their initials along with a numerical designation. Machine operators bagged each excavated find and placed an identification label with the artifacts. After being surveyed by the metal detector, crew members mapped all flags by pulling survey tapes from the nearest point on the stp grid and marking them on a field map. This field map was later transformed into an Autosketch file (Figure 3.4).
Four areas were examined using metal detectors. The first area was the grass lawn to the west and south of the structure. Metal detector sweeps moved along the stp grid to ensure complete coverage, and machine operators excavated all hits in this area. The area below and to the west-northwest of the structure was examined using a single transect sweep starting at N745E200 and heading 75 ft north. Machine operators also excavated all hits in this area. The grade to the north of the structure was examined for evidence of outbuildings. Hits in this area were mapped with only one hit excavated. The final area examined was on the southern portion of the property and north of a tributary to Bull Run, and the machine operator selectively sampled this area and excavated all hits. Excavation units served to sample the area near the structure. As a result, metal detector sweeps were not conducted in this portion of the site.
Metal detector sweeps revealed five areas of historic artifact concentrations (Figure 3.5). Discrete concentrations of artifacts define the boundaries of these five areas. However, in the case of Concentrations M4 and M5, survey methodology created the appearance of artifact concentrations rather than artifacts actually concentrating in a discrete area. The largest area, Concentration M1 is to the south of the structure and contained 48 artifacts. Concentration M2, found to the west of the structure, contained 24 artifacts. To the west of Concentration M2, metal detector sweeps revealed 18 historic artifacts (Concentration M3). Concentration M4 is to the north of the structure. Concentration M5 is on the southern portion of the property.
Concentration M1 is south of the structure and measures 100 ft north-south by 75 ft east-west. Metal detector sweeps recovered 48 historic materials in this area. Most of the materials are bottle glass-related (n=17), along with four cut nails, a harmonica plate, three large caliber rifle shells, and seven unidentified iron fragments, and four whiteware fragments. These materials may represent a light sheet midden scatter relating to the Davis occupation. Concentration M1 also contained modern materials relating to National Park Service occupation including a ring for a camera lens and five Lincoln pennies. Tourists probably dropped these items while visiting the site. Metal detector sweeps found other modern materials such as a fragment to a distributor cap, and an automotive manifold gasket fragment. These materials might be associated with the Woodward occupation of the structure.
During the Davis household occupation, the area might have served as a garden and may have received light trash scatter for mulch. Artifacts dating to a later occupation, such as the manifold gasket and distributor cap fragment, suggest the use of the area for repairs. The tourist related materials document the use of the area by the public as a recreational area.
Concentration M2 is downslope and to the west of the structure. Concentration M2 is 35 ft north-south by 100 ft east-west. Metal detector sweeps in this area revealed a total of 24 historic artifacts. These include four nails, a furniture lock, a window blind hanger, a key, two screw caps, a pull tab, a cast iron stove fragment, a crown cap, a buckle, a harmonica plate, a fragment to a toy gun, five unidentified iron fragments, and a 12-gauge shotgun shell. The manufacture dates of these materials range from the mid-nineteenth into the mid-twentieth century. The wide date range and distribution of materials makes interpretation of this area difficult. However, the presence of hardware and metal scraps close to Concentration M3 might reflect use of the area for Thornberry=s wheelwright activities.
Concentration M3 is to the north of Concentration M2 and at the base of the hill where the structure sits. This spot is next to the former roadbed of Sudley Road. The size of this concentration is 80 ft north-south by 22 ft east-west. Metal detector sweeps located 18 items in this area including five horseshoes, an early twentieth century medicine bottle, a large iron pin, a carriage step, a U.S. Army Great Seal button, and eight unidentified metal scraps.
The high number of transportation-related artifacts at Concentration M3 show some specialized activity taking place in this area, such as John Thornberry's wheelwright shop. The Atkinson Map of 1861 shows his shop near the crossroads of Sudley Road where the road turns sharply to the west toward Sudley Mills (Figure 3.6).
Concentration M4 is to the north of the structure and adjacent to the high knoll on the northern extreme of the property. The area of Concentration M4 measures 25 ft north-south by 65 ft east-west. Only one of 28 metal detector hits was excavated. The machine operator, Bob Marcus, stated the remainder of the hits registered as small items, more than likely nails. In lieu of excavating these hits, a 2.5 ft by 2.5 ft excavation unit was placed in the center of the concentration.
This area of metal hits roughly corresponds to the location of an outbuilding constructed by the Woodward family. Local resident John Crews recalled that the Woodwards built the structure to store garden equipment (John Crews 1998, personal communication).
Concentration M5 is on the southernmost portion of the property around 520 feet south of the structure. Bob Marcus selectively swept this area by metal detector, and all hits in this area were flagged and excavated. The area of hits measures 40 ft north-south by 65 ft east-west. Nine artifacts were recovered in this area, including three shotgun shells, a cast iron stove fragment, three cut nails, and two unidentified pieces of iron. This area might be the location of an outbuilding.
Metal detector sweeps at Sudley Post Office allowed the identification of five potential cultural resources: a low density sheet midden, two activity areas and the location of two potential outbuildings. Concentration M1 appears to be a light scatter of materials to the south of the structure. Residents of Sudley Post Office might have used this area as a garden and scattered trash in the area for fertilizer. The two activity areas identified, Concentration M2 and M3, are potentially the location for John Thornberry's wheelwright shop. These concentrations are to the west and downslope of the structure. Concentration M2 also contains some late nineteenth to early twentieth-century scatter. A combination of metal detector findings, oral history, and documentary sources identified the location of two outbuildings (Concentration M4 and M5). Concentration M4 is at the southern extreme of the property. Documentary sources (Harris Map of 1861) show a structure present in this area; this structure might have served as the dwelling for John Thornberry's two slaves.