Wednesday, 9 April 2014

The end of the dock dig

Last Friday Oxford Archaeology North completed the archaeological excavation of George Quayle's 18th century dock at the Nautical Museum, Castletown. Readers of previous posts on this blog will already know that our expectations had been quickly confounded as soon as the first skip of spoil was full. Now, 160 tonnes of spoil later, what did they find, and what's next for Quayle's boat house?

The excavated dock, looking towards the sea arch

In this picture you can clearly see the outlines of the dock. It's under at least a foot of water at all times. The remains of the inner gate are slumped at the end - we had to stop excavating at that point in case the rubble infill under the arch began to collapse upon us. It's just one of several things that remain to be dealt with. You can see submerged timbers on the left side of the picture: the dock was neatly lined with timber, but most of the lining has gone. Less easy to see are the beautifully laid stone flags that line the base of the dock. One of my first jobs is to plan the construction of a temporary scaffold platform to pull Peggy out upon (for more information on this see my previous posts from early 2013). Cue further meetings with scaffolders and engineers.

In the foreground of the picture is a jumble of wheels and other objects. These are all fused together.

Unidentified, fused mass of machinery and rubbish

You'll no doubt be able to make out a pair of cast iron wheels as well as any number of unidentified submerged objects (today we'll call these USO's) along with nineteenth century bottles. The whole pile is sitting on a layer of wood chips and saw dust on the bottom of the dock. It would appear to be the remains of some kind of machinery or contraption, and because of it's archaeological context we can date it to the Quayle period. It seems to have been dumped in the dock after the  latter had fallen into disuse and disrepair. At some point not long after somebody dumped a whole load of cement mortar or plaster on top of it - it's this that has fused the whole lot together. It looks to me like Portland cement mortar - proper analysis might confirm this - and this would be very interesting since Portland cement was not patented until 1824. Traditional lime mortars, such as those used to build the dock, don't set when wet.

Fused mass with cement

I am currently working on a plan to remove this mass of stuff, separate the pieces and record it. I also have to find a temporary home for the 1000 other archaeological finds. We are looking at going through all the finds this summer, possibly using local volunteers to help. Allison Fox, our Archaeology Curator, will be instrumental in this phase of the project.