Steadying the ship | The Mary Rose
Steadying the ship
Collections | 06 Dec, 2022 | The Collections Team
Monitoring the Mary Rose's movement by James Harvie, Weston Heritage Conservation and Heritage Science intern

Even though it has been nearly 500 years since the Mary Rose last set sail, the ship is still moving. Such movement is to be expected and it is down to the conservators at the Mary Rose to monitor and understand this movement, ensuring that it remains under control. Working as the Weston Heritage conservation and heritage science interns in summer 2022, my colleague and I created computer code that will make monitoring the ship's movement and identifying areas of concern an easier and more efficient process.

Despite its current home on dry land and the fact that the Mary Rose last set sail in 1545, the Tudor ship is not finished moving. Though in this case, no matter how close you were to sit in the museum and look at the ship, you wouldn’t be able to tell. This movement is on the scale of millimetres over the span of years, as the Mary Rose shifts and adapts to its current condition and environment.

This movement is far from unexpected and occurs for multiple reasons. For example, not only is the ship nearly 500 years old, but the Mary Rose was designed to sit in water where its hull could be fully supported. It now finds itself in a cradle on dry land, and the ship is now only partially complete meaning that some beams and sections aren’t as fully supported as they once were. The wood is also partially degraded from time in the marine environment. Whilst treatments have been used to combat this, it cannot be completely remedied, and some movement due to this is expected.


Image - Close-up of a crack marker on a timber of the hull

Just because the movement is expected does not mean that it is ignored. Every aspect of the ship’s movement is carefully monitored by the conservation team. Some of the movement of the ship is recorded using an automated total station, a tool usually used by building surveyors, which measures the distance to reflective markers placed around the ship three times a day. Over 400 individual cracks, joints and areas of interest are also marked out by small wire markers, which are recorded manually every year. If you look closely at the ship when you next visit, you may even see some of these small flags or reflective markers.

As can be imagined, these measurements result in a huge quantity of data, filling up numerous pages of spreadsheets, each time they are recorded. As Interns, we developed a method to quickly sort and analyse the data recorded from these markers and present it in a clear and concise way. We wrote code using the computer programming language Python to achieve this. First of all, the code creates a text report that would run through the data and pull out key information such as missing entries, average deck movements, and high movement cracks. Then it colour codes the spreadsheet with all the measurement recordings on it, based on the level of movement, allowing conservators to identify any areas of concern. Finally, it calculates the average movement for each bay of each deck of the ship, creating a graph to indicate the amount of movement.

Image - Using a crane to access the crack markers on the upper decks

This code will allow for the movement occurring on the Mary Rose hull to be monitored in a much more thorough and efficient manner, as well as allowing the information to be displayed in a more digestible format. This will help us understand any future conservation work required due to the movement of the ship. It just goes to show the different disciplines that can be called upon to aid the conservation of a 16th century warship!