Blue whale on the move: the de-installation of the skeleton | Conservators

Although it’s only been a few weeks since I looked at ‘what lies beneath,’ it feels like a lifetime as so much has happened to our blue whale skeleton in a relatively short space of time. The biggest challenge of de-installing the skeleton from the Mammals Hall has been completed with resounding success and the Conservators are now busy with the next phase of cleaning and conserving each individual bone.

Photo of the vertebra from above, wrapped in tape with a label to describe its position on the skeleton,

The first caudal vertebra, showing the metal loop used to keep it in place on the armature

We all knew that safely removing the bones from the 81 year old armature was not going to be easy. Add in the fact that it was suspended over a large model of a blue whale and several other specimens with very little room for manoeuvre and you start to appreciate the whale-sized nature of the project. This post outlines what happened during the de-install.

After careful planning and the labelling of the skeleton, we were ready to start with the smallest caudal vertebrae. The first task was to remove the plaster covering the very end of the tail section so we could release the initial vertebra.

Underneath the plaster the first challenge presented itself in the form of two steel metal rods embedded through the bone which had been fashioned into a loop at the end thus preventing the first vertebra from being removed.

After carefully applying a small hacksaw (which would come in handy throughout the project) the loop of metal was carefully cut away and the first bone was ready to be removed.

The move begins – conservator Lorraine Cornish and curator Richard Sabin take the first steps toward the deinstallation of our blue whale skeleton ahead of its move to Hintze Hall. After 81 years suspended in the Mammals Hall with minimal contact, the team behind the blue #WhaleMove need to know if the skeleton will be strong enough to sustain the dynamic pose planned for its new home. Go behind the scenes with Richard and Lorraine in our new short film as they shed light on the scale of the task ahead. Watch the full film in the Discover section of our site (link in profile). #BlueWhale #Whale #Skeleton #Bones #Conservation #NHM_Conservators #BehindTheScenes #Docunpmentary #NaturalHistory #Museum #NHM

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It’s worth noting at this stage that, in order to remove any of the vertebrae, the plaster modelled intervertebral discs had to be chiselled away so that the central armature could be seen and the vertebrae loosened from the mount. This was further complicated by the fact that underneath the plaster there was a large number of wooden splints and wedges holding each vertebra firmly in place. These were often nailed directly into the bone by our predecessors all those years ago. So some reverse engineering was needed to extract each bone from the armature.

The next 3 caudal vertebrae were even more challenging as the internal armature increased in size and complexity. This took the form of several steel metal rods, plus a rectangular iron bar bolted in sections, that was to run throughout the vertebral column.

Photo showing the gap between two vertebrae, with nails in a vertebra and the metal bar support exposed.

The metal bar, rods, wedges and nails used to mount the caudal vertebrae in the 1930s

As the vertebrae increased in size the armature became slightly more predictable but each bone was a challenge to remove as it was so firmly wedged onto the internal metal bar by the wooden wedges.

After the first 8 caudal vertebrae were removed the next problem had to be tackled in the form of the cable suspension metalwork which was bolted into the armature and effectively blocked the removal of more vertebra.

Photo showing the cable joint between two vertebrae on their metal supporting rod

A cable-sized blockage to the removal of more vertebrae

A support gantry was wheeled into place and a sling was placed under the exposed metal armature to support the structure and the first cable was uncoupled. More vertebrae could then be removed and each safe removal caused great joy amongst the Conservators.

Photo showing two conservators smiling as the vertebra is being removed

Happy Conservators during the safe removal of another caudal vertebra

As each vertebra was removed the team learned more about how the skeleton was articulated and mounted onto the armature and soon the process became more predictable. There seemed a certain elegance in the vertebrae as they waited to be removed. Anyone think of aeroplanes when they look at the image below?

Photo showing the metal support with a vertebra partially removed and the other vertebra in place. The 'wings's of the vertebra give the image the appearance of a plane flying.

The skeleton takes on an aeroplane-like appearance during the removal of the vertebrae

Further along the vertebral column, other skeletal elements had to be removed to ensure progress towards the skull, including the chevrons, sternum, scapula, radius, ulna, phalanges and ribs. Each was bolted onto the armature or had additional armature attached and in some places the Conservators had no choice but to cut through some metal rods to ensure safe removal.

Photo showing one of the conservators cutting through a metal rod holding one of the ribs in place, with another conservator helping by supporting the rib bone.

A hacksaw was deployed to carefully cut through some parts of the armature holding bones in place, such as this rib

When the team reached the cervical vertebrae removal of the modelled intervertebral discs that had been inserted between the bones during the original installation, was more time consuming as the vertebrae were closer together. However the added bonus was that the team discovered that a large quantity of newspaper has been used as packing material.

Photo showing the conservators assessing the spine near the base of the skull, where the vertebrae are much more compact

The Conservators extract the wood, plaster and bits of paper used to create the intervertebral discs, a process that became more difficult where they became closer together near the skull.

Photo of a fragment of the packaging material used to make the intervertebral discs in the 1930s

Part of the inside content of one of the man-made, intervertabral discs, showing newsprint from the early 1930s. We’re intrigued to find out what our counterparts were reading back in the early 1930s.

The newspaper pieces , dating back to between 1932-1934 will be preserved where possible to add to the archive documentation for this project. One piece may well find its way back inside the specimen once it is re-suspended in the Hintze Hall in 2017. Watch this space.

As the vertebral column was taken down more space was created on the scaffolding to check, wrap and pack each bone. Conservation approved materials were used to protect the bone surface such as Tyvek (polyethylene sheet) and Plastazote (blown polyethylene foam sheeting).

Photo showing bones at different stages of being wrapped and protected for removal, lying on the scaffolding

Skeletal parts being prepared and ready for removal from the scaffolding

The next stage involved removal of the two parts of the mandible. Blue whale mandibles are the largest single bones of any animal to exist and both sides have large cracks around their existing metal armature so extra care was needed to move them.

Once some of the scaffolding was re-built to allow easier access the first challenge was to excavate around each bolt connection and uncouple the mandibles from the skull whilst providing full support to each element.

Photo showing conservators chipping away the plaster around the bolt

Removing the plaster fill around the front bolts inserted through the mandibles. This was necessary to enable the removal of the bolt and the separation of the two mandibles.

Each mandible was then packed into a bespoke wooden frame so it could be carefully lowered down to the floor of the mammal gallery. The mandibles were too large to move internally to their new home in the Pop Up Conservation studio so they had to be hoisted out through a side exit in the wall of the gallery and down onto a HIAB (lorry with integral crane) waiting in the colonnade below.

Photo showing the wrapped mandible on a wooden frame prior to hoisting

Just one of the huge mandibles of the whale, being prepared for hoisting down to the ground and its move into the Darwin Centre on a bespoke wooden frame

This was no easy task and there was much manoeuvring to ensure they “landed” safely on the lorry. They were then driven around the perimeter of the Museum so that they could be taken in through our entrance in the Darwin Centre. Once they were transferred into the entrance by the wonderful and versatile HIAB crane, they were wheeled into the Pop up Conservation Studio that has been created for us there, ready for treatment. There was relief all round at this point, but everyone was aware that the greater challenge of removing the skull lay ahead.

Photo from behind the mandibles in their wooden frames, with the conservation and moving team in the background

The mandibles and the very relieved team in the newly installed Pop up Conservation Studio located in the Darwin Centre

After the 2015 festive break the team reassembled to spend a week taking down the skull. The skull is almost 6 metres in length and three metres at its widest point. It is highly complex in shape with over individual 40 elements fused or partly fused together.

The first challenge was to lift and move it without placing any strain on the bone. The second challenge was that, due to existing cable supporting the whale model underneath (which could not be moved or removed), the skull was going to need to be rotated as we moved it, so that it would fit through the gap between the cable and the side of the scaffolding to enable it to be lowered to the ground floor of the gallery without damaging anything.

This was the biggest challenge of all. A cradle had been designed to be placed underneath the skull and existing holes and bolted areas of the skull were used to attach it to the cradle. The Conservators were extra vigilant at this stage ensuring that as much support could be given to the skull to ensure it would stay attached to the cradle. Crack monitors had been placed at existing vulnerable parts of the skull to provide an additional recording mechanism for cracks opening up during the process.

Photo taken from where the tail vertebra was looking down the scaffolding towards the skull, as its frame is being put in place

When we started, we were here. In the distance, the final part of the blue whale skeleton – its enormous skull – is prepared for removal via the use of a specially constructed frame. Note the restricted space due to the various cables supporting the model of a blue whale hanging below.

Photo showing a plastic device attached to the underside of the skull, across a pre-exisiting (and repaired) crack in the bone of the skull

A crack monitor placed on a pre-existing fault in the skull, used to assess the stresses and strains of the removal of the biggest bone in the skeleton to our stores

Extra removable sides were then added to the cradle, to provide extra protection for the rotation and subsequent move.  The team managed to decouple and move the skull down to the ground of the Mammals Hall and then onto the HIAB though, at times, there were literally centimetres to spare!

A major #WhaleMove moment from our #NHM_Conservators this #WhaleWednesday: the massive skull is the final piece of the blue whale skeleton to be successfully removed from the Mammals Hall, where it has been hanging since the 1930s. The blue whale cranium, or upper part of the skull, is shown here on its way to the Museum's stores, where it will reside while our team of Conservators prepare it for installation in Hintze Hall next year. Now, the next job is to remove the scaffolding erected in the Mammals Hall, ready for it to reopen to the public on 23 Jan. Find out more about the #WhaleMove and other changes happening in Hintze Hall here: http://bit.ly/NHM-HintzeHall-Redisplay or follow the link in our profile. #Skull #Skeleton #BlueWhale #Whale #BehindTheScenes #NaturalHistory #Museum #NHM #MarineMammal #Mammal #Balaenopteramusculus

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The skull is now safely stored in one of our off-site stores and will be undergoing treatment over the next few months as it was too big to treat at the Museum. Conservation methods and treatments will be covered in my next post but, in the meantime, why not pop along to the Darwin Centre in the Museum, to our newly created Pop up Conservation Studio. There, you can see how we are getting on with the conservation of the mandibles and other parts of our blue whale skeleton.

Photo showing the exterior of the Studio, looking into it via a window, with the mandibles on show

The newly installed Pop up Conservation Studio in the Museum’s Darwin Centre, where you’ll be able to see how we are progressing with the work on the mandibles and other parts of the blue whale skeleton

 

2 thoughts on “Blue whale on the move: the de-installation of the skeleton | Conservators

  1. Phil

    Very interesting, gaining a huge appreciation of the work, skill and patience that’s involved to complete the move to its new home.

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