To celebrate British Science Week (8-17 March 2019), we will be posting a series of blogs over the next 10 days to showcase the excellent work of heritage scientists in using science and technology to understand, manage and engage with heritage.
First up is a piece by Angela Middleton (HE), with contributions from Kim Roche (MSDS), Alison James (MSDS), Ruth Pelling (HE) and Peta Knott (NAS).
Citizen science can take many shapes and forms; such as taking part in the Big Butterfly Count, searching your archives and collections for images of actual leather hats or getting hands on and learning something about the science behind the conservation and analysis of maritime artefacts from the Rooswijk.
Together with the Nautical Archaeology Society, conservators, archaeobotanists and material scientists from Historic England have devised a programme of workshops to bring the science that underpins many archaeological post-excavation projects to a wide range of participants. The artefacts and samples used in these workshops originate from the @Rooswijk1740 project: a collaboration between RCE (Rijksdienst voor het Cultureel Erfgoed; Dutch Cultural Heritage Agency) and Historic England, and managed by MSDS Marine Ltd. Starting with a geophysical survey in 2016, the project recovered over 2000 artefacts during two underwater excavations in 2017-18. The artefacts have since been transported to Historic England’s research and conservation facilities at Fort Cumberland, Portsmouth.
The material from the Rooswijk project not only presents researchers with interesting and unique material to study, but is also well suited to help satisfy a growing appetite to engage with archaeology in a very interactive way. Participants to the courses come from all walks of life with varying levels of archaeological experience: retired marketing executives, recreational divers, social workers, archaeologists, etc., all united by an interest in archaeology.
The courses are a well-balanced mixture of theory and practice. The morning is dedicated to learning about decay processes of archaeological materials commonly encountered in the marine environment, the theory of X-Ray Fluorescence (XRF), or the significance of environmental archaeological samples on shipwrecks. The afternoon allows participants to use the same tools and techniques that archaeological scientists use every day. In small groups of no more than four, various practical activities are being undertaken. The small groups allow for a more intimate learning environment and give every participant the chance to carry out each task, whilst the tutors can fine tune the activity according to different levels of confidence and experience or interest. Practical sessions include changing of storage solutions, mechanical cleaning and material identification of artefacts as well as identifying environmental samples collected from the Rooswijk site and within artefacts.
Participants monitor the desalination process using a conductivity meter, which measures the amount of dissolved salts. Maritime artefacts have to go through a lengthy process of washing out salts, as these can be harmful to a wide range of materials. This is achieved by regularly changing distilled water solutions in artefact storage containers. This process of water changes facilitates desalination and also gives participants the opportunity to handle a lot of different materials from the site.
During cleaning activities, we allow participants to use a variety of tools, such as an air-scribe (a small-scale pneumatic chisel), air-abrasive or air-brush to remove concretions or corrosion deposits. This is almost always guaranteed to be the favourite activity of the day! Another group works carefully under a microscope cleaning coins or packages them for storage after conservation.
The material composition of metal artefacts is analysed in a live demonstration of the XRF. After a spectrum is produced by the software, participants attempt to match different elements to the peaks to identify the composition of the material.
The archaeobotanist demonstrates various sampling techniques, and participants can sort the flot under the microscope by testing their recognition skills and working through the identification process. On first glance it may just look like soil or mud, but with a bit of practice, they are able to pick out seeds and even identify some distinct examples.
During these workshops, participants’ efforts contribute to the often lengthy and repetitive tasks during the scientific investigation after an excavation. What is more important to us, is that we provide hands-on access to heritage, a look behind the scenes and develop an understanding and appreciation of archaeological science processes.