Bluetooth temperature data logger protects Magna Carta

The best surviving copy, which is currently on exhibition in Britain’s Salisbury Cathedral to commemorate its 800-year anniversary, is stored in a glass display cabinet along with an Onset HOBO MX1101 Bluetooth temperature and relative humidity data logger that protects it by monitoring the cabinet’s environment around the clock.

However, as the display cabinet is sealed and protected by alarm systems, there was no way of constantly monitoring temperature and humidity without going through a time-consuming and complicated process of switching off the alarms and accessing the case. To address these issues, the cathedral’s exhibition team installed the MX1101 logger which they purchased through Onset’s UK distributor, Tempcon Instrumentation.

The self-contained wireless data logger, which works with Onset’s free HOBOmobile app for logger setup and data management, enables Cathedral staff to access the environmental data anytime from a mobile device having to open the cabinet.

Having inspired and encouraged movements for freedom and constitutional government for hundreds of years, the four remaining copies of the document have been awarded Memory of the World status by the United Nations Educational, Scientific and Cultural Organisation.

“The HOBO MX1101 is a suitable solution for us to protect such an important historical artifact as Magna Carta,” commented Naish. “It’s great that I can check the current conditions at a glance and have the ability to access historical data without interfering with the exhibit.”

“Preserving the text is of paramount importance,” said Emily Naish, Archivist, Salisbury Cathedral. “Excessive humidity can cause parchment to buckle as it tries to revert to its natural shape. The parchment can expand while the ink remains static, causing ink to lift from the text. As the display in which Magna Carta is displayed has large glass windows, it is prone to these kinds of damaging fluctuations in humidity.”