07 October 2014
800 year old Magna Carta manuscript reveals its secrets
Ground-breaking multispectral imaging work of the British Library’s burnt copy of the 1215 Magna Carta has recovered text which has not been read in 250 years.
This work has been completed by British Library conservators and scientists in preparation for next year’s 800th anniversary of the sealing of the Magna Carta. The so-called ‘burnt’ copy of the Magna Carta is one of four original manuscripts from 1215 which survive. In February 2015, the four manuscripts will be brought together for the first time in history for a special 3-day event, which will allow further academic study of them side by side, as well as the once-in-a-lifetime opportunity for 1,215 people to view them together.
Figure 1: Top left: The “Burnt Magna Carta” ready for multispectral imaging. Top right: A real colour image of a section of the charter. Bottom: A processed image of the charter enhanced to reveal text thought to be lost.
The British Library owns two of the original 1215 Magna Carta manuscripts (the other two are held at Lincoln and Salisbury Cathedrals). The story of the ‘Burnt Magna Carta’ (Cotton charter xiii 31a) held in our collections is a truly remarkable one of survival against all the odds. In 1731 it was damaged in the Cotton Library fire, and subsequently staff at the British Museum Library used 19th century techniques to try to flatten and mount it, which has contributed to its current condition today rendering the text very difficult to see.
The multispectral imaging of the burnt Magna Carta was conducted as part of a major project involving the reframing and scientific analysis of all the Magna Carta charters held in our collections ahead of the 2015 anniversary. The Collection Care team provided an initial examination of the original frames to determine their structure and composition. All original mounting materials in contact with the charters were tested using infrared spectroscopy, pH tests, and lignin tests to determine their stability and compatibility with new materials. Once the charters were removed from the frames, near-infrared spectroscopy and high resolution digital microscopy was used to investigate the condition of the ink and parchment as part of the overall condition assessment.
With the frames and glass removed there was a rare opportunity to employ the cutting-edge technique of multispectral imaging enabling us to virtually peel away the layers of damage currently affecting the manuscript.
Figure 2: Clockwise from top: Temporary housing is prepared to store the charter when removed from the frame; the original wooden frames are removed to enable access to the charter; the charter is released from the mounting; once the charter is free from the frame it can undergo condition assessment.
Figure 3: Left: The “burnt” copy of the Magna Carta, Cotton charter xiii 31a, is one of the four original manuscripts from 1215 which survive. Right: Much of the ink has been lost with only a few remaining initials (shown here at 50x magnification).
Multispectral imaging is a non-destructive, non-invasive imaging technique using different colour lights, including ultra-violet and infrared, to recover faded and lost text. A high-resolution camera is securely mounted directly over the charter, which is then illuminated with LED lights ranging from the ultraviolet at a wavelength of 365 nm, through the visible region, and right up to a wavelength of 1050 nm in the infrared region. The chemical composition of the material in the charter is varied (ink, parchment, etc.), and so reacts differently to the lights. We are able to see, and capture, additional information undetectable by the human eye.
Figure 4: An animated gif comparing the original colour and processed images.
Figure 5: A colour UV image reveals regions of text which are completely faded to the naked eye.
Using this technology and expertise available to us in the 21st century, we are able to preserve the Magna Carta for the next 800 years and present these iconic documents in the best possible condition for visitors who come to see them during the anniversary year.
Multispectral data is still being processed and will be published along with other scientific data collected after the British Library’s exhibition ‘Magna Carta: Law, Liberty, Legacy’, which runs from 13 March – 1 September 2015.
Christina Duffy (@DuffyChristina), Imaging Scientist