What we did posts only click here

Tuesday, 10 June 2014

Guest Post by Beverley Rogers: Peering Beneath the Layers

Peering beneath the Layers
The day we took ‘Rover’ for a walk

by Beverley Rogers

As Carolyn, Wendy and myself walked into the Faraday Building on the morning of 30 April, the students and staff, noticing that Carolyn carrying a big box in her arms, kindly opened the doors to allow us to pass.  They had absolutely no idea what we were carefully guarding as we carried on through to the Engineering Department in time for our appointment with Dr. Richard Johnston.   They may have been more than a little surprised had they known- for inside the rectangular box, delicately protected in tissue, was ‘Rover’ the Egypt Centre’s mummified dog (EC438).

The three of us had come to meet with Richard to discuss the results of an exciting collaboration which has risen between The Egypt Centre and two of the colleges from Swansea University.  The Institute of Life Science and the Engineering Department, together with the Egypt Centre, are helping to bring Egyptian antiquities ‘back to life’ by allowing mummified remains to be unwrapped without evasive procedures.  As part of this project, we had brought ‘Rover’ along to see if he was a suitable candidate. 

Richard, Senior Lecturer in Material Science in the College of Engineering, greeted us in his laboratory, which houses an impressive x-ray machine and a 3D scanner.  Digital imaging is key to this collaboration, for several of the mummified objects held in the Egypt Centre’s collection have undergone 2D, 3D scans and CAT scans over the last few months to determine what is inside their mummified wrappings.  The results have been truly astonishing. 

It should be said that it is not the first time that Richard has worked on projects with a historical theme. Richard has worked with the Mary Rose Trust, where human remains from the Mary Rose have been x-rayed.  He has also previously assisted Egyptology at Swansea by working with Dr. Kasia Szpakowska in her research on clay cobra figurines and their ritual breakages, by analyzing the experimental fractures of modern made objects.  The idea to apply digital technology to objects from the Egypt Centre came to him last year.  “It is very rare to have such an important resource on campus” Richard told us.  ‘We wanted to take advantage of that”.  After pitching his idea to curators Carolyn and Wendy, a selection of mummified animals were chosen for the first scans.  Both Carolyn and Wendy had warned Richard that often a ‘cat mummy’ or ‘bird mummy’ may in fact turn out to be something completely different – a bag of dislocated bones perhaps, or twigs and debris wrapped up to resemble the supposed animal.  The results when they came through however were more than could have been hoped for.

2D Imaging

Four objects have undergone 2D imaging so far –  two cat’s heads,  a bird mummy and a further body of a cat.  Results show that the scan of one of the cat heads seems to be no more than a bag of bones, however the bandages with its layers and fibers have come up so well that the individual strands of the weave can be seen.  This in itself is exciting!  The second cat head is an actual skull and clear cracks can be seen indicating damage. The bird mummy was revealed to have a perfectly intact skeleton and the imaging is so detailed that it could easily be identified as to what type of bird it is by the right kind of specialist.

Richard showing us the cat’s head before digital ‘unwrapping’

Scans of the cat’s head from different perspectives

Scans of the other cat -  originally from the Aberystwyth collection – literally blew the three of us away.  It is perfect in its detail and, the ability to rotate the image on the screen, allowed viewing to be seen from all angles and the high resolution of the scanning showed remarkable clarity.  The cat’s ears are situated above its head and are shown separated from it.  You can also see that there has been a lot of damage to the skull in the region of the right eye socket.  The cat also seems to have a full set of teeth which suggests that it was not old when it died.  These scans are so clear that further research could be undertaken to look at age of cat and type of cat by a feline specialist.  The manner of death could also be a source of further investigation.

Aberystwyth cat mummy showing dislocation of ears

Close up of the Aberystwyth cat showing Damage to skull by the right eye socket

Amazing detail of the teeth of the cat mummy
All images are to be given to the Egypt Centre for their future display within the galleries and outside foyer.  A huge thanks must be given to Jack Christie – 3rd year graduate student in the College of Engineering- for the use of his research images.

3D Imaging

3D imaging, is I must admit, completely new to me.  Richard’s lab is kitted out with both a 3D scanner and printer, and I was keen to learn how it works.  I will attempt to explain in layperson’s terms.  Once an object is scanned, a 3D model of the object is printed using plastic.  The raw material, which is fed into the printer from above, looks exactly like strimmer cord, which you see used in garden mowers.  It is relatively inexpensive and lightweight to use and produces very realistic and intricate detail.  An example shown to us that day was a model of the Eiffel tower (see below), created recently by Richard’s team.  It was made up of the most exquisitely complex struts and layers.

Wendy and Carolyn with 3D scanner in background.

Richard demonstrating the 3D scanner

Richard shows us the plastic cord used to create 3D models

3D model of the Eiffel Tower

The ways in which this type of printing can be used is becoming more and more numerous and this type of printing will certainly become more popular as time goes on.  One use that has recently hit the headlines at the time of writing this article is in the production of casts for limb breakages.  The design allows ultrasonic treatment to be transmitted through the cast and  can be hooked up to an ultrasound machine that promises to reduce the time it takes for a broken bone to mend. The cast is lighter, better for the environment and more comfortable than bulky plaster ones.

3D Plastercast

In terms of how this technique can be used in Egyptology research, well Richard was able to show us a first hand example.  Some months ago, the Egypt Centre had agreed to lend artifact number EC308 – labeled in the archive records as a mummified snake – to the College of Engineering to see if there was an animal within the bundle of linen.  When scanned, and a 3D model of the contents produced, it did indeed reveal that there was a complete snake within the bandages.  The 3D model took 10 hours to print due to the complexity of its shape; the mass of ribs on the snake meant that the scanner had to print a scaffolding structure to support the printed object so it can build up the shape (the scanner cannot print in mid-air but instead has to be supported by a structure.  An example of the supports can be seen below).   It can be a real nightmare to remove the supports, hence the 10 hours taken to complete the model.  On the plus side however, what was then left was an accurate representation of the ancient snake without there being any harm done to the linen in any way.  Richard also showed us high resolution images of the snake on screen.  This allowed us to travel virtually through the snake, from its head to its tail.  It was a strange experience but one that was mesmerising.  There appears from the scans to be some anomalies in the snake, specifically a number of strange protusions coming off the body – to the untrained eye they were almost like thin pipe-cleaners! Part of the jaw and head are also missing. 

The snake has featured recently on the BBC One programme ‘Rhys to the Rescue,’ presented by Dr Rhys Jones, a wildlife adventurer and Cardiff University lecturer.  Both he and Richard Johnston examined the scans and Rhys identified the snake as a young cobra.  Two objects were noted as being lodged in the mouth but identification is difficult.  The objects appear dense in matter and Carolyn has suggested that it may have been food placed in mouth.  
The copy of the video is to be given to the Egypt Centre for showing on the display screen in the foyer and research is continuing: Carolyn is going to send the images to animal mummy specialist Salima Ikran to analyse further.  For those of you that are interested in seeing the snake model, it is now displayed in the Egypt Centre next to actual mummified snake on display in the House of Life.

Bundle containing a mummified snake

3D printer with model of Egypt centre snake in front of it.  Inside the 3D printer, can be seen 3 curved arches, which were the scaffolding left over from a previous print.

3D scan of the snake

The collaboration with the Institute of Life Science (ILS) has also been the inspiration of Richard who put the Egypt Centre in touch with their CT scanning department.  They have the capacity to carry out scans of some of the larger objects in two dimensional data.  ILS have recently CT scanned the mummy of a baby which is enclosed within its cartonnage cover.   This object has been the subject of much speculation over the years, most notably because the hieroglyphs on the front of the cartonnage are confusing and unreadable.  It has often been speculated that that the mummy may in fact have been a fake so when the Egypt Centre were given the opportunity to put this mystery to bed, they seized upon it.  It wasn’t just the Egypt Centre staff who were excited at learning the truth however - the mummy scan created a lot of interest in the medical department as well; all the department staff were eager to take a look at their new ‘patient’. 

The results came back within 3 hours and confirmed that the cartonnage contains a foetus estimated to be at around 12-14 weeks old.  Remarkably, the shape of a head can be seen.  There could also be identified a possible fringe or string of beads contained within the wrapping (a similar example has been found in the British Museum where a baby mummy has been shown to have a string of beads wrapped with it).  The scan may also show an amulet within the wrappings but the angle is difficult to positively confirm.   The images of the CT scan are also going to be given to the Egypt Centre for display with the object.  News surrounding this discovery has been phenomenal.  Publications announcing the results of the research have included The Telegraph, Live Science, Discovery and the South Wales Evening Post.  It even appeared on the news in Canada!

The cartonnage coffin of the baby foetus

The scanning of the Egypt Centre mummified remains is a wonderful example of inter-disciplinary collaboration and it seems that the marriage of Egyptology and scanning techniques is growing even more in popularity.  Some museums are going down the laser scanning route, such as the Smithsonian, who are undertaking a huge project to scan the millions of artifacts in their collection.  This technique allows for the objects to be spun around on a digital database where all angles of the piece can be viewed at the click of a button.  The Smithsonian are going to make this data available on-line so that anyone around the world can use it to obtain scan data and be able to print images for their research.  Laser scanning, which was also used for the Mary Rose project mentioned above, shows a great deal of detail and allows for colour to be incorporated into the scan.  It does have its limitations however as a lot less information is captured from using surface scanning.  The British Museum have also used both x-rays and laser scanning for mummified objects, again with the potential for people to observe these digitally.  Museums are also creating displays with which to showcase the work undertaken via imagery.  Sweden has produced digital autopsy tables, which allow specimens to be ‘unwrapped’ by computer rather than be hand, so allowing for a great density of mummy and unwrappings to be exposed, layer by layer.  It is great interactive technology but at the moment it is very expensive. 

Will this create problems for future museums in that people will not have to go to or want to see the original if they can get scans online?  The general belief from our animated discussion that morning was that this wouldn’t be the case.  It was felt that people would still want to see the original rather than a replica, as there was something magical about observing originality (a bit about that from the curator's view here). The museum also creates an environment that adds to the visitor experience, which cannot be replicated in database access.  

What to the future?  Well, further objects will be identified as suitable for scanning either in 2D or 3D.  ‘Rover’, the mummified dog, was a little too big to scan in Richard’s lab that day so he will shortly be off to ILS to undergo scanning and we wait to see what lies beneath the wrappings.  There are also endless possibilities to which digital imaging technology could help Egyptology research.  For example, when objects are drawn, there can be many different interpretations of them – the 3D printing technique would produce an accurate copy without the problem of human interpretation.  Or imagine a situation where 3D scanning can allow students and visitors to ‘peer’ beneath outer wrappings of objects without causing damage and these models being used as a handling resource.  Think of the researchers who are undertaking work on specific objects – what if they could have their very own copy of the artifact with which they could then transport around with them?  The 3D technology could be used to make mounts for objects; it would avoid damaging the real object when trying to sculpt a base to achieve a close fit.  Or how about being used to make copies of original amulet moulds and the replicas then being used to make amulets in the same format as they would have done thousands of years ago?   Exciting isn’t it?  We certainly came away thinking so!

‘Rover’ the mummified dog

Carolyn, Wendy and Richard discussing scans

Images courtesy of Wendy Goodridge and Beverley Rogers.  Scanning images are reproduced with kind permission of the College of Engineering and remain the intellectual property of the same.