So, we finished what I expect will be the final round of Ground Penetrating Radar (GPR) at Burial Hill in Plymouth today (May 15, 2015) and what did we find…nothing. Well, that’s not exactly true, we did find a lot of evidence for the 1778 mass grave of the crew of the Brig Arnold, but that’s another story. What we did not find was anything definite that related to the 17th century forts or palisades that were up there. We know they were there from the historic records (Plymouth Colony records and visitor’s accounts) but we didn’t know what they looked like, and I guess we still don’t. But, what we have discovered is what they did not look like. All of our dozen or so scans across both of the hills on Burial Hill, the southern one traditionally assumed to be the location of the forts and the higher one to the north, yielded no evidence of a palisade trench or significant disturbance that would have been caused when a building with even a relatively deep foundation would have been erected. From this we can conclude that the palisade was not erected in a trench, but probably consisted of a series of large posts spaced equidistantly with a rail at the top and bottom to which split logs, or more probably sawn planks, were trunnelled in place. Is there precedent for such a construction? Yes there is? Where you ask? Why right in Plymouth on Burial Hill in 1635. The palisade that had been erected in 1622 was in rough shape by 1633 and needed to be replaced, the work was to be carried out by all the able bodied men of Plymouth. The palisade was rebuilt in 1635 and Thomas Boseman was hired to “do the fort” the posts were to be 10” square, to be not over 10’ apart, with three rails between, and boarded nine feet high, cut sharp at the top; all the lumber to be sawed.” Fort at this time apparently referred to a fortification and not a fort building like what had been originally built there. The only evidence of this sort of palisade would be post holes measuring maybe 2′ in diameter spaced up to 10′ apart. Very difficult targets to identify with anything but stripping off the topsoil over a very large area and which is like finding a needle in a haystack in the dark using GPR.
The fort was rebuilt in 1675 at the start of King Philip’s War:
“It is ordered by the town that there shalbe forthwith a fortification build upon the fort hill at Plymouth: to be an hundred feet square the pallasadoes to be 10 foot and one halfe long: to be set 2 foot and an halfe in the ground; and to be set against a post and a raile; every man is to doe three foot of the said fence of the fortification the Pallasadoes are to be battered on the backsyde one against every two and sharpened on the topp to be accompomplished by every male in each family from sixteen yeares old and upwards and that there shalbe a watchhouse erected within the said ffence or fortification and that the three peeces of ordnance shalbe planted within the said ffence or fortification.”
Traditionally, a slight bit of what looks like terracing on the south and east sides of the the summit of Burial Hill have been associated by some researchers with this 1675 fort. Our GPR scan across these terraces have shown that they appear to be completely natural terraces that resulted from glacial and erosion action. They aren’t human made.
What of the fort? The best description of the fort was by the Dutch ambassador Isaac DeRaisier in 1627. He described it as a large square house, with flat roof made of thick sawn planks, stayed with oak beams, upon the top of which six cannon were mounted. The lower part was used for a church. This was built around the same time as the palisade and it appears to have been sheathed in sawn planks, which may support the idea that the palisade was also sawn planks. The whole fort was timber framed and was strong enough to support six cannon on the upper story indicating that it was apparently a well-built structure. This does not mean that it was well founded or supported though. The sills may have sat directly on the ground surface or on a thin layer of fieldstone that in turn rested on the ground. Remove the stones, remove the timbers, and you have no traces left. Add to this the fact that no one lived on the top of Burial Hill until the 1670s when Samuel Jenney briefly inhabited the 1642 watch house. He was also given leave to take the structure away since his had been destroyed during the Native’s attack on his home town in Dartmouth. The foundation for this structure, which measured 16 x 12′, was encountered when Abigail Judson’s grave was being dug in 1884. Our GPR survey readily identified the foundations as well, giving us confidence that if the original fort had rested on a fairly substantial sub-surface foundation, we would have found some trace of it.
One thing that we had found in 2013 and that we saw again in 2014 and 2015, was what appeared to be a 10 ‘ (east to west) by 20′ (north to south) rectangular pit extending from 1-4’ below surface and containing a number of boulders measuring between 12 and 18″ in diameter. This anomaly extended beneath the Warren burial lot whose earliest grave dated from 1707. This means that it dated to before that date, providing us with the earliest possible evidence of European occupation on the southern hill of Burial Hill. What was it? The only known building aside from the fort/ meetinghouse was the watch house and we know where that was. But why would you have what appears to be a cellar beneath the fort/ meetinghouse? A little incident in 1622 when Hobbamock saw the English digging up barrels of gunpowder buried beneath their storehouse and asked if it was the plague that had killed so many of the Natives just before the English arrived (as Squato had been telling people). The colonists may have built a powder magazine in the fort to keep their powder as was found in Jamestown, and this may be what that anomaly is. Or it may be something else, the only way to be sure would be to excavate part of it.
We then figured, well, maybe the fort was on the northern hill of Burial hill, the higher hill with the more commanding view of the harbor. So, we did several GPR scans there and turned up…nothing, actually even less than on the south hill, so probably not here as well. But, why didn’t they put the fort with its cannons on this higher hill? Who knows. It would make sense to us today to put them there, but maybe to them it didn’t. Maybe the gain in height was not worth the loss of the symmetry of the fort to the lower village. It appears that the town was set up using the traditional English Motte and Bailey as its model. In this defensive plan, the Motte, the fort, sits on the highest point and the bailey, the town, sits on the lower slope of the hill. The entire thing is surrounded by a palisade. If the community was attacked, the palisade would have held the attackers out initially, if they breached the walls, the population would have fallen back to the Motte, the defensible keep or fort on the top of the hill, to hold out against the attackers. In the case of Plymouth, it is also known that they erected a redoubt at the crossroads in the center of the town. On the redoubt were placed four pateroes that could have been loaded with anything small from a single shot to a bunch of rock to nails. These could have been used to repel attackers using a scatter gun attack as they came through the gates and down the streets. The placement of this redoubt indicates that the possibility of wall breach and invasion into the town was present in the colonist’s (Standish’s?) minds, making a Motte and Bailey defensive strategy very reasonable. In such a strategy, the fort is traditionally right at the head of the town, not off to one side as it would have been if they had erected it on the highest hill on Burial Hill. Pu the gun deck on top of the fort and you have a direct shot out to the harbor, right over the town and right over Long beach directly into deeper water where attacking ships would most likely be.