Discovery and Conservation

For many years the Museum had been proud in the knowledge that it possessed two of Smith's great maps: one a set of 15 sheets bound together as a book; the other, beautifully preserved, nestles in its leather travelling case. Every couple of years it is displayed for a day in the department to excite another generation of geology students. In May 2013, a third copy was rediscovered in the collection. Found folded in a box with some other early geological maps, it was easy to miss. Unfolding the map had to be done with care as it gave the appearance of not having seen the light of day since Queen Victoria was on the throne. This was clearly in contrast to the prolonged exposure it had endured during her reign, as it looked as though this hand-coloured map had been exposed to the light for many years. The colours were faded, the paper stained and it carried the stains of faecal deposits from long dead spiders and flies that had used it for their regular battles.

What to do with such a map? The reaction of the librarian of the Department of Earth Sciences, Sarah Humbert, who had relocated the map, was clear - it needed to be hung in the museum for all to see. Who could disagree with that? Given that, to the best of our knowledge, despite the map's great importance, no other public institution has a William Smith map on display, this seemed a wonderful idea. Then reality set in. The map would need conserving, restoring and somehow framed in such a way that it would see off, hopefully, many more reigning monarchs. With the realisation that the 200th anniversary of the first publication of Smith's map was fast approaching, what better time to display it than on August 1st, 2015.

With financial assistance from the Friends of the Sedgwick Museum, restoration and conservation was undertaken by the renowned paper conservator Nicholas Burnett and his team at Museum Conservation Services in Duxford. The principal aim has been to make the map available for permanent public display without compromising its long-term conservation. Much 19th Century dirt and grime was carefully removed, then the original, faded water-colour paint was given a protective coating and subtly restored to enhance the colour of the rock formations. Smith was at great pains to choose the appropriate colours for his geological units - the New Red Sandstone obviously had to be red; the yellow Jurassic limestone of Lincolnshire clearly yellow, and so on. This colour scheme he introduced is still used on the British Geological Survey maps of Britain today.

Restoring colour to the faded cheeks of the map was a challenge. Fortunately the two other copies of the Smith map held by the museum are in superb condition, having been hidden from the light for 200 years. These more pristine maps have allowed us to get a good indication of what the map would have looked like in its heyday. However, one of the challenges was to know exactly how to restore it, for the simple reason that Smith didn't just produce 400 or so identical copies of the same map. All of the maps are thought to have been produced over at least a four-year period. During that time Smith continued his geological research and was forever making new discoveries and needing to adapt and amend the map, no doubt much to the frustration of the map maker, John Cary. But the technique of hand-colouring the maps at least made this possible. Smith's nephew, the geologist John Phillips, recorded that it took seven or eight days for each map to be coloured. Our map is thought to have been coloured by one Mr Morse.

After the recent restoration work, the map had to be mounted and glazed. Permanent display requires protection, especially from the damaging effects of light, and the use of a non-reflective, anti-static glazing material that would block out UV light was paramount. Once glazed, the map’s weight was a concern – it was expected to weigh about 90kg, consequently traditional glass was not suitable. However, the generous donation of a special museum quality acrylic called ‘Optium’ from glazers Tru Vue has solved the problem and will ensure the map's future protection as it cuts out most of the UV light.

After the first few maps had been produced, Cary and Smith introduced a numbering system for the remainder and he signed each one individually. This was probably his way of signing off on each map once it had been completed to his satisfaction. Research carried out in the 1930s established that the maps fell into five series. The restored map has the number a,91, making it the last known of Series III. Smith signed off on the map on January 23rd, 1816. Each series has some changes to the colouring of the geology which, in some parts of the map, are quite significant. Thus, establishing where our map falls in the production sequence was crucial for ensuring that any colour restoration was faithful to the original colour scheme.
 

 

Stripping the Earth Bare: William Smith's 1815 Geological Map
1st August 2015 - 31st July 2016
The First of it's Kind
Learn more about the history and creation of the map and it's designer William Smith

 

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