Excavating one of the Crossrail construction shafts
Right on the edge of Charterhouse Square itself
We came across an amazingly well preserved archaeological site
25 burials, buried around 25 meters below the ground level
and this location, historically is within the area that we think was associated
with one of the emergency burial grounds of the Black Death, set out in 1348
This site is one of the most important archaeological sites that we have got, because the period
of the Black Death,
the mid 14th Century, is not well understood through archaeological excavation.
It;s quite a rare opportunity to find an archaeological site that is so well preserved
It's one year on from the excavation work we did, and during that time we have done
a series of scientific studies, to really try and tie down the results of the excavation.
And we have come here today to the Charterhouse, who are very kindly hosting an event,
so that we can present those results, starting with the discovery on London and the Black
Death.
A lot of work that has gone into the past year has been about understanding the dating,
initially,
and we have done that through dating the finds that we have got associated with the skeletons
but also taken samples from the skeletons themselves to undertake radio carbon dating
Along with that the other big question has been, what did these people die of?
Are they associated with or can we associate these individuals with the Black Death itself
With the Plague
And again, taking tiny samples from the skeletons and applying an ancient DNA analysis to those
has allowed us to identify the DNA of the pathogen - Yersinia pestis
Which caused the Plague and still carries on today to cause the Plague
So these two crucial pieces of evidence, we have now nailed down through this analysis
work
Well first of all these are a very rare resource
and we don't want to do anything to make them rarer
We don't want to use half of the skeleton in scientific testing
We have to be reasonable about, if we do any testing we only take small amounts from the
skeletons
So first of all what we did, we chose half of the skeletons and we took one tooth from
each of those skeletons
So 12 tooth samples
They can now look at the DNA within ancient bone and tooth and find out what diseases
the person was exposed to during life
And then we used the same tooth, what was left from the tooth, and that was sent off
for radio carbon dating
Stable isotopes are something that accumulate in the tooth from things that a person eats
and drinks and we can use various chemicals and stable isotopes to look at where a person
grew up
Out of the 10 individuals where we got data back for stable isotopes
six of them were definitely brought up in London
and four of them came from elsewhere
and it's likely that three of them came from East or Southern England
One came from the North of England or Scotland
The area was pretty much open fields, so it was a nearby parcel of land
Owned by the local church, which the London Authorities at the time purchased
specifically to manage what they expected to be a devastating Plague event
They had heard about the Black Death creeping across Europe and this was some kind of premeditated
preparation
and a very good opportunity to have a precise window into this historical period
which was ultimately probably the most devastating period of London's history
Historic references suggest up to 200 a day were passing down Charterhouse Street to be
buried in this area
and extrapolating that over the size of the burial ground which was stated as 13 acres
or seven hectares
A huge area, a huge number of burials, that haven't yet been discovered
So the point of the geophysics was to try and see if we can trace more burials in the
immediate area
and to see if we can start extrapolating the numbers up to understand how many are buried
in the area
Still yet to be discovered