Monday, March 25, 2013

Finding Fort Hollingsworth, Part IV

Today we're pleased to bring you the fourth entry in a five-part series by Jim Gibb detailing the search for (and discovery of!) Fort Hollingsworth in Cecil County, Maryland...enjoy!

Where was Fort Hollingsworth? What did it look like and what happened to it after the war? These are questions investigated by the Archeological Society of Maryland in 2011 and 2012, with one of its chapters—the Archeological Society of the Northern Chesapeake—taking the lead.

The Baltimore Patriot, the local newspaper at the time, provides the only construction details: a semicircular breastwork approximately 300 feet long with a ditch large enough to accommodate 500 soldiers. The reminiscences of Thomas J. Sample in 1880 and the name of the fort—Fort Hollingsworth—place the fortification on Zebulon Hollingsworth’s farm at the confluence of the Big Elk and Little Elk creeks, just south of Elkton. The Hollingsworth farmhouse and surrounding fields were acquired by the Town of Elkton and the Historic Elk Landing Foundation restored the house as a museum.
Hollingsworth House
The State of Maryland holds an historic easement on the property and has prohibited intensive archaeological investigation, allowing only limited studies to assist the Maryland Historical Trust in managing the site’s archaeological resources.

Since the local archaeology chapter was interested in securing permission from the Trust to hold the Society’s annual field session in archaeology at Elk Landing, they commissioned Peter Quantock, then a master’s student at the University of Denver, to conduct a magnetometer survey of the lawn between the Hollingsworth House and the now wooded marsh to the south. The mapped magnetic anomalies suggested a linear feature—possibly the fortification—beneath the seemingly level lawn.

The magnetometer survey in progress.
Anomalies beneath the surface!
A local firm, Stephens Environmental Consulting, conducted a detailed topographic survey of the lawn in March 2012. The resulting map revealed subtle variations in the topography that matched the magnetic anomalies. Bill Stephens and I then tested the property with a 4-inch diameter bucket auger capable of recovering soil samples from 12 feet and more below the ground surface. We found an area in which soils typical of those from two to three feet deep across most of the lawn and adjacent cornfield appeared just one-foot below grade.

Subtle variations in the topography
All evidence pointed to our having found the fort. To hedge our bets, the Society commissioned Peter Quantock to return to the site, this time armed with ground-penetrating radar, courtesy of Dr. Larry Conyers, his advisor at University of Denver. This survey, also conducted in March 2012, covered the same ground over which Peter had run the magnetometer. The machine emitted energy pulses into the ground and measured the time and intensity of the return signal…much as conventional radar works in the tracking of aircraft and ships. The resulting map showed a well defined anomaly…a linear pattern of strong, rapid return signals…that corresponded with the magnetic anomaly, the surface contours, and the soil anomalies. We found the fort!

The radar imagery that identified Fort Hollingsworth!
Of course, finding the fort and proving that we found the fort are not quite the same thing. We finally persuaded a skeptical Maryland Historical Trust to allow us to conduct test excavations to prove that we had found the trench. Permission granted…provided we excavated no more than forty square meters, less than 400 square feet, or an area a little larger than my home office. We did it in twenty-eight square meters. The Society’s field session crew excavated a nearly contiguous line of fourteen units, each measuring one meter by two meters, or about 3 ft by 6 ft, extending from well south of where we thought the ditch was located to a point well within the presumed fort interior.

Unit 1 was the southernmost unit, Unit 3 the northernmost, and Unit 2 was placed where we thought the ditch was located. Unit 2 came down on the ditch and the intervening eleven additional units provided a single trench in which we could clearly see the full width of the ditch. Nothing but scattered gravels remained of the earthwork in this portion of the fort.

With this bit of ‘ground-truthing’ it is possible to reevaluate the radar data and, using the survey data collected by Bill Stephens, to accurately stake the ditch on the ground. Future excavations, if permitted, should reveal remnants of the earthwork and, possibly, gun emplacements and evidence of militia bivouacs. The portion of the ditch that we excavated revealed that the fort was demolished simply by shoveling the earthwork back into the ditch, sometime after February 1815. The land reverted to cultivation. And so we achieved our goals of finding and documenting Fort Hollingsworth. Additional radar and excavation could reveal internal structure of the fort, such as gun emplacements and militia camps. But we don’t know how it compares with other forts built by citizens at the same time…that will require finding and investigating those sites. More about that in the next post!

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