The history of British shipping goes back to the arrival of the first visitors from the mainland, but not much is know about the physical structure of the ships before the end of the medieval period because few viable shipwrecks have been found. That changed recently when maritime archeologists from Bournemouth University on the southern coast of the UK verified the remains of ship which sank 750 years ago in nearby Poole Bay. The vessel is known as a ‘clinker’ but this discovery is no clinker – part of its cargo is gravestone slabs that the archeologists say will rewrite the history of how the cemetery markers were produced.
“Recent storms had revealed something unknown on the seabed. I was granted permission to dive the wreck. The rest is history! I've found one of the oldest shipwrecks in England.”
Charter boat skipper Trevor Small shows his excitement in the press release over his find in 2020 in Poole Bay. ‘Poole’ is a form of the Celtic word ‘bol’ a place near a pool or creek and the town of Poole dates back 2500 year ago to its days as a Celtic port and settlement. The Romans invaded in the 1st century and used it as a fishing and shipping port. Poole survived Viking invasions in 876 and 1015 and maintained its importance as a southern port to modern times – it was the third-largest embarkation point for D-Day landings of Operation Overlord. However, its shallow bed made Poole Bay treacherous for heavy transport ships. Trevor Small was able to find the wreck and dive to it because recent storms had revealed something unusual on his normal route. (A video of Small, the wreck site and some of the revered cargo can be viewed here.)
“Very few 750-year-old ships remain for us to be able to see today and so we are extremely lucky to have discovered an example as rare as this, and in such good condition. A combination of low-oxygenated water, sand and stones has helped preserve one side of the ship, and the hull is clearly visible.”
According to Bournemouth University Maritime Archaeologist Tom Cousins, what Small found was a clinker ship. “Clinker” is a boat design where the edges of hull planks overlap each other rather than meeting edge to edge. Originated in Scandinavia, it was common on longer vessels known as cogs and were popular during the early medieval period. Examples of clinker design today are the round-bottomed Thames skiffs and the cargo-carrying Norfolk wherries of England. Analysis of the tree rings on the timbers used on the ship discovered by Small show they came from Irish oak trees felled between 1242-1265. Irish oak was widely used by shipbuilders, so this boat was not necessarily built in Ireland.
“The 13th century ship with its cargo of medieval Purbeck stone is fascinating because it is the earliest English protected wreck site where hull remains are present.”
According to Duncan Wilson, Chief Executive of Historic England, the cargo tells more about the ship’s owners. Purbeck stone or Pureck marble was quarried from limestone beds on the Isle of Purbeck, Dorset in southern England. Although Purbeck marble was highly valued by European builders because it could take a high polish, analysis of these stones indicates most of the cargo of this so-called “mortar ship” was destined to be made into round grindstones for grain mills. However, two of the Purbeck marble slabs were to have been used for a different purpose – one that could change the history of marble grave markers.
“Even this early stage in the investigation, it has been clearly demonstrated that two cross head designs which were previously thought to be part of a developmental sequence were actually in use at the same time. Further work on the wreck is very likely to greatly enhance our understanding of the work of the medieval Purbeck marblers.”
These two slabs were the only two in the cargo hold that were finished and carved. This is unusual because most polishing and carving was done by local craftsmen after the marble had arrived at its destination. These are an early example of the formation of an industry built to finish the product at or near the quarry – possibly an early form of mass production and a definite threat to local marble workers.
Brian and Moira Gittos from the Church Monuments society explained in the press release that these were two different gravestone slabs from two different periods – one had a wheel headed cross in an early 13th century style, while the other featured a splayed arm cross that was common in the mid-13th century. (You can see photos of the stones and the rest of the cargo here.) Prior to this discovery, it was thought that the splayed arm cross evolved from and replaced the wheel headed cross design, but this is a clear indication that both were used at the same time.
Other items found in the wreck include a cauldron used to cook food in, mortar bowls used for grinding grain, cups, pottery and other kitchen objects. What caused this mortar ship to sink so early in its journey in Poole Bay? One theory is that the medieval ship may have been too heavily loaded for the shallow Poole Bay and Swash Channel and the load may have shifted, causing it to tilt and capsize. As more of the wreck and its cargo are recovered, they will be placed on display in one of Poole Museum’s three new maritime galleries when it reopens in 2024. The site is protected, so only divers with permission are allowed to explore it and recover the cargo and timbers.
Surviving wrecks from before 1700 are extremely rare, so this discovery has become one of 57 Protected Wreck Sites in English waters. Making it even more valuable, the wreck was found in the Solent – the strait between the Isle of Wight and Great Britain that has long been a major shipping lane for passenger, freight and military vessels. While the low-oxygenated water helped preserve it, it’s a miracle it wasn’t damaged or destroyed by other ship traffic.