 |
Hide or Leather Beetle
|
 |
Silverfish
|
Today we're taking a closer look at the work of the paper conservation team at Sheffield City Archives and in particular the 'pest problem'. One of the many problems encountered in the preservation of old records is that they've quite literally been eaten away. The very stuff of archives - paper, leather,
vellum, hair, cloth, wood and glue - is an excellent source of food for insects
and other critters. Some of the material
we’ve received over the years has been riddled with tell-tale holes - often
with the offending creature(s) still present.
This is where the work of our Conservator comes in…
 |
Sheffield documents that suffered damage
from fire, water and mice. Now conserved
and safe from further deterioration.
|
The Conservation Unit, in short, perform miracles when it
comes to documents that have had a hard life and are fast perishing. From wax seal repair to the delicate
treatment of ancient manuscripts, the Conservator and Preservation Assistant work
in a meticulous and precise manner to ensure the continued preservation of our
unique documents for many years to come.
 |
Brown House Moth
|
One of their main tasks is to inspect all incoming
archive material for potential problems.
People have a habit of storing old papers in damp cellars and draughty
garages - fertile breeding grounds for beetles, silverfish, mice and
woodlice. Each year we receive hundreds of boxes of new material into the archives; as soon as it comes through the
door it needs to be isolated immediately.
The Conservator checks for evidence of insect invasions: tell-tale signs
include holes in paper, tunnels bored in wooden frames, frass (small piles of
fine, dry, powdery insect excrement) and exuviae (shed skins of insect larvae
that have pupated). Insects are
particularly drawn to the cellulose and starch (plant sugars) and collagen and
keratin (animal protein) in archive materials.
Arresting potential problems quickly is key: the staving off of the
insect’s oxygen source, the use of pheromone traps and occasionally
deep-freezing (using a specialist off-site company) are all tools the
Conservator can employ. It is crucial
that any insect issues are dealt with in an isolated area to ensure an
infestation does not occur in the main strongroom.
 |
Woodlouse
|
 |
Woodworm
|
The humidity of an environment can play a critical role
in the survival of insects. The
strongroom at Shoreham Street has state-of-the-art environmental controls
(which conform strictly to British Standard PD5454 2012) and fluctuations in
humidity are carefully monitored on a daily basis by our Preservation
Assistant. Achieving a stable
environment is a finely balanced act and a swing either way (in terms of
temperature or humidity) can give rise to problems which pose a threat to the
stability of the documents. If the
environment is humid above 65% relative humidity (rh) mould and insects are
likely to be active.
 |
A completed treatment on a 300-year old volume.
|
Once stabilisation has occurred, the Conservator examines
any documents that have started to be eaten away. In some cases rescue is impossible: a mouse
can make quick work of a box of paper.
More often, though, we find that insect attacks and woodworm invasions
can be arrested reasonably successfully.
Where paper has begun to disintegrate, the Conservator will stabilise it
using a combination of conservation tissues and Japanese infill papers to
replace the missing pieces and strengthen the structure of the item. Our aim is to make documents robust enough to
handle again whether by conservation treatment or preservation packaging (or
both).
 |
Evidence of woodworm in the wooden cover of the
Beauchief Cartulary which dates from the 1400s.
|
If you’re storing your own precious family papers in a
precarious location at home, it might be worth checking to make sure they’re
safe. Deeds, old photographs, personal letters,
war memorabilia and so on are irreplaceable.
If you need any advice on these matters from our Conservator, please get
in touch: Conservation.Library@Sheffield.gov.uk We also offer a bespoke Conservation service
should you have any documents or books that require repair. Again, please contact us for details.
In the meantime, keep your eye out for the pesky critters
(pictured) and take a look at some of the archives in Sheffield that survived
attack and lived to tell the tale…
