Light

Over the centuries, many visitors have found Knole to be a dark house. Back in the 1600s, the diarist John Evelyn was apparently so depressed by greyness of ‘this great old fashioned house’ that he had to hurry out into the sunlight. Today, some of our visitors still comment on the Knole’s often shadowy interior.

 

knoleinteriorportraits

A house that ‘smoulders rather than sparkles’.

 

Many find this atmospheric lighting an integral part of Knole’s unique charm. But for the Conservation team, monitoring and controlling the light levels in the house is a key part of how we look after our fantastic collection. Obviously, we want our visitors to be able to see the beautiful objects. However, displaying our collection while minimising the damaging effects of light, is a constant challenge.

 

knole-brown-gallery-15

This suite in the Brown Gallery was once a vibrant purple colour but has heavily faded in the light. 

 

When light falls on the surface of an object it provides energy. This induces a chemical reaction in the molecules of the material, which causes physical changes including the structural weakening of the fibres and a change in colour. The damage caused by this reaction is cumulative and irreversible. How vulnerable different materials are to light varies, but textiles particularly are highly light sensitive. We have the largest collection of English Stuart furniture in the world to have survived. It is internationally significant and we want to ensure that these magnificent pieces can be enjoyed for generations to come.

A key part of our work involves monitoring the light levels in the show rooms. If you look carefully at some of our furniture, you may notice small rectangular cards with a square of blue wool in the centre. These are called dosimeters and we use them to monitor the effects of light. They are placed on or near light sensitive objects and left in position for a year. Part of the blue wool is exposed while the other part is protected. When the dosimeter is removed and sent off for analysis, a measurement is made of the degree of fading. How much the blue wool has faded depends on the amount of light it has been exposed to. The conservation team also conduct regular checks to measures both the UV and the intensity of the light (lux) and we have two Hanwell LUX/UV monitors on the east and south sides of the building, which send back information to a computer in the office.

 

dosimeter1

Knowing the fade rate of the blue wool allows us to accurately measure how much light objects and rooms are exposed to.

 

 

The most effective way to protect our collection is by preventing it from being exposed to too much natural light. We now have case covers on the furniture in the Spangled Dressing Room, to protect the incredibly fragile and deteriorating fabric. Historically, case covers have been used to protect special pieces of furniture in grand houses from the ill effects of light and dust. Should an important person come to visit the covers could be removed to reveal the textile underneath. Our red custom cotton case covers have been carefully made by upholstery conservator Heather Porter to ensure that each piece of furniture gets the individual protection that it requires.

 

8

One of our brand new case covers in the Spangled Dressing Room

 

The most damaging part of the light spectrum is ultraviolet (UV) and sunlight contains a high proportion of UV. Where possible we try to filter UV out by using a film on the windows of the show rooms. The light levels in the rooms are kept low and we only expose the rooms to light when it is necessary. However, the current electric lighting in the show rooms is inefficient and ineffective, meaning our collection is often poorly lit. This is something being addressed by the project. A scheme for new lighting has been designed by Sutton Vane Associates. Historic light fittings will be fitted with LED bulbs, which will not only significantly improve the presentation of the show rooms but will also help protect our collection.

150122-knole-lighting-trial-report

This is from a trial conducted at Knole in the Brown Gallery. You can see how the proposed LED lighting will not only protect the vulnerable materials but really highlight our fabulous collection.

Volunteer Experiences

We’ve been very lucky recently to have been joined by a new conservation volunteer at Knole who’s spent a few months with us to lend a helping hand. He has very kindly written a little about his experiences with the team!

Volunteering at Knole

The single greatest and most interesting part of being a Conservation volunteer at Knole has been the immense variety of tasks and small projects that are undertaken by the conservation team.

Involving everything from cleaning 18th century caffoy fabric to waxing the lead fish tank in stone court, it is hard to say that being a Conservation volunteer at Knole entails two even similar days. With the nature of the larger restoration project at Knole, as well as the day to day running of any property of Knole’s size the outlets for conservative work is seemingly endless.

The Monday deep cleans are the best chance to work on the items which are either vast or extremely precious, requiring more time and specialist equipment than many other of the usual but by no means insignificant objects. Utilising specialist material brushes as well as museum vacuums in my opinion the most fascinating part of the deep clean has been the work on the Orangery statues as well as the Roman busts of stone court. Whilst the cleaning of the Great Screen using cloth and ladders is also spectacular, if you think the screen is not amazing enough.

Screen

The Great Screen was built c.1605-08 when Thomas Sackville did much to create the Knole you see today. The impressive edifice is bristling with heraldic symbols.

Being involved in the caffoy cleaning project was also highly rewarding. Once again the opportunity to use specialist conservation equipment and follow the stringent methods used to transform the fabric highlighted how precious Knole’s textiles really are. This time it was novel to use smoke sponges and once again low power vacuums to restore the caffoy. I can say that the process of removing a few hundred years’ worth of grime from the fabric was the most rewarding part of all of the mini projects which I have helped with over the last two months.

The caffoy material normally lines the Cartoon Gallery. During July 2016 we gave this piece a thorough clean!

The caffoy material normally lines the Cartoon Gallery. During July 2016 we gave this piece a thorough clean!

Another untold perk of being a volunteer in the conservation team here at Knole is that you truly get to experience the full character of the property, through objects, the different conditions and periods of each parts of the house, some of which is publicly accessible. Being able to see items which the team have restored or conserved is also fulfilling and history creating in itself.

All in all I have thoroughly enjoyed what seems like a very short couple of months at Knole with the conservation team and cannot overstate how fundamental they are to the condition and running of Knole as one of the country’s greatest properties. I would recommend to anyone who has even a slight interest in conservation or history in general to give conservation volunteering at Knole a go.

-Matthew

 

A Stitch in Time

Summer is here and the conservation team has been hard at work making a start on the textile cleaning.

If you walk around the showrooms at Knole, you may notice that we have rather a lot of furniture. In fact, Knole is home to the largest collection of Royal Stuart furniture in the world. It is internationally significant. Much of this vast collection of chairs, footstools and sofas, as well as two state beds, was acquired at the end of 17th century by Charles Sackville, 6th Earl as one of the perks of his office as Lord Chamberlain under William and Mary.

DSC04326

A stamp on the underside of one of our pieces of furniture, showing that it came from Hampton Court Palace.

By bringing this collection back to Knole, the 6th Earl was not only underlining his connections and influence at court. He was also acquiring pieces that, while they were no longer required by the monarch, were real status symbols. To be seated was a sign of authority in the 17th century, an honour only accorded to the most important person. Footstools were also often used, not only because of the imposing size of the chairs, but also because raising the feet of the ground was in itself, a symbol of wealth and status.

10 Leicester P 200

Portrait of James I, seated in a Chair of State, from the Leicester Gallery

Furniture, now mostly mass produced, has lost the intense association with wealth and status it once had. But 400 years ago, the pieces of furniture at Knole were expensive luxury objects. They were the result of thousands of artisan hours, made using the finest woods and the most expensive fabrics, drawn from across the known world.

These items of furniture may not have the same significance as they once did. Their magnificence has also dulled with the passing of time. The fabric is now extremely fragile due to the damage caused by light and relative humidity. Today, as readers will already know from previous blogs, we constantly monitor the environment in the showrooms and our storerooms, so we can keep an eye on the relative humidity and the amount of light the textiles are exposed to. Part of the huge conservation project currently taking place at Knole is to install special conservation heating and lighting in the showrooms, so we can control the environmental conditions in the house.

We also clean each item. As well as dusting the frame to remove dust and cobwebs, the textile is cleaned with a conservation vacuum on low suction with a soft brush attachment. Although the frames get dusted regularly, the amount of attention each textile receives depends on its fragility. While some are cleaned annually, other more delicate pieces are cleaned less frequently, every 3, 5, 10, or in some cases, every 20 years.

knoleinteriorportraits

The Brown Gallery at Knole.

But if you look closely at the surface of most of the upholstered chairs we have in our collection here at Knole, you may notice some of the conservation techniques that have been used to look after these unique objects.

On some items, areas of the upholstery have been carefully stitched to secure and stabilise the original fabric. Many of pieces have netting applied to the surface of all or part of the textile. The net is a mono filament nylon, dyed beforehand to match the colour of the original material. It temporarily stablises areas of weakness, preventing loose fibres and threads from coming away with a minimum of intervention. It also helps prevent further degradation or damage to the fabric, prolonging the display life of a textile.

5

An example of netting on one of our stools.

This means our magnificent collection of furniture can continue to be enjoyed for many generations to come.

 

Cleaning Caffoy!

For the last two weeks the conservation team, along with a group of volunteers, have been busy cleaning a section of the caffoy from the Cartoon Gallery. This was removed by specialist textile conservator Zenzie Tinker, as part of the work to decant the second half of the house last winter.

IMAG0427

The caffoy in its original position in the Cartoon Gallery.

 

 

Caffoy is a rich, red coloured wool fabric, similar to velvet, with a floral pattern stamped into the pile. It dates from the 18th century and was used for wall hangings and upholstering some of the items of furniture that we have in our collection. This particular piece covered the wall at the east of the Cartoon Gallery.

 

Decanting the rooms - Knole House 2016

The east wall of the Cartoon Gallery after being cleared of the caffoy.

The back of the caffoy was lined with course linen. Interestingly, in the areas covered by paintings, large rectangular sections were cut out of the caffoy to reveal just the linen. This practice was a way of ensuring that the expensive fabric would not be wasted behind areas that would not normally have been seen. However, it did mean that over time, as and when the picture hang changed, sections of caffoy had to be added to fill in the exposed areas of the linen lining. There are 56 such pieces, some regularly shaped and fixed neatly with stitching, others placed haphazardly, cut in irregular shapes and fixed with tacks. This indicates that there were at least two different picture schemes, as well as the original plan, for that one section of wall.

While these small patches of caffoy have been taken offsite for specialist conservation work, the front and back of the main piece of textile has been carefully cleaned by the team here at Knole.

The caffoy was very dirty with a layer of dust, cobwebs and insect debris on the surface.

 

IMAG0372 (2)

Melinda, a member of the team, cleaning with a low powered vacuum.

Following the advice and training of Zenzie and her team, the textile was divided into workable sized sections, roughly 35cm by 35cm, marked out with pins and white thread. We then worked on each of these sections in turn, making sure that we kept a careful eye on the timing so each area received the same level of cleaning, ensuring we didn’t get any patches that were cleaner or dirtier than the rest of the textile!

 

IMAG0366 (2)

The has been separated into individual squares for precise and even cleaning.

First, each section was vacuumed using a conservation standard vacuum cleaner with a small brush attachment. The suction on the vacuum was set to a specified pressure to avoid causing any damage to the textile fibres.

Next, a smoke sponge, made of vulcanised natural rubber, was used to remove soot damage and general dust.

IMAG0434

A clean piece of smoke sponge against a piece already used to clean a section of caffoy.

Finally, the surface was vacuumed to remove any sponge residue.

You can see the results!

Untitled

A clean piece of linen against a dirty piece.

 

 

Next week, the back of the caffoy will be vacuumed to remove any dirt and dust before the whole thing is rolled and put into storage ready to be reinstated, along with the small patches that have been removed, in the Cartoon Gallery next year.

 

The other sections of caffoy which cover the walls in the rest of the Cartoon Gallery, as well as those in the Reynolds Room, will be worked on, in situ, by the conservation team before the second half of the house is open to the public next year.

Decanting the rooms - Knole House 2016

We’re looking forward to seeing it back home!

Spot checks!

One of the most important things we do at Knole is keeping an eye on the environmental conditions in the Showrooms. We do this through a combination of ways. Our primary method is using individual monitoring sensors in each room that send a regular signal back to the office detailing the Relative Humidity (RH) and temperature in each space. By this method we can keep an up to the minute record of what’s going on.

IMAG2822

Our regular ‘Hanwell’ environmental monitors. This one is in a storage space and is showing an RH reading of 58%, right where we want it.

However, because of our current project and the work going on to improve the lighting, conservation heating and all sorts of other things it means that we don’t have proper radio monitors in some rooms right now.

 

photo

RH in some rooms sometimes reaches worryingly high levels. It’s essential to keep a good watch on what’s happening.

 

This means that our secondary method become more important and we have to do it more regularly. This method is using spot checks. Usually we go into each space in the showrooms and store rooms every two weeks to take temp, RH, lux and UV readings to make sure that our automatic monitoring is consistent with our handheld sensor.

While the sensors are gone in the second half of the house we send the intrepid Zena in with a hard hat and a monitor to take readings every week. This way we know what kind of conditions the historic showrooms are facing on a day to day basis in all weathers.

IMAG2815

Zena taking readings in the Ballroom

Which is Witch?

Here at Knole we are blessed with many fantastic volunteers. Our volunteers contribute in all sorts of ways; whether it be Room Guiding, helping the conservation team, admin or mucking in with our Premises team, they’re always here to help.

One of the more little known contributions of volunteers at Knole is in the field of poetry! There is a strong literary tradition at Knole with Thomas Sackville, 1st Earl of Dorset and man most responsible for Knole as you see it today, being a respected poet in his day. From Thomas in the 17th century right down the generations to the 20th century. Vita Sackville-West was a successful writer and poet and her cousin Eddy a novelist and music critic.

Today some of our volunteers take up the mantle of poet with Clare Fallows, a 42 year veteran of Knole producing several wonderful poems about the place.

Clare has been a stalwart here at Knole and has recently written a fantastic poem about the witch marks we are continuing to uncover here at Knole. She has kindly allowed us to share it with you here. I hope you enjoy it as much as I have!

 

Which is Witch?

Now down at old Knole there are witch marks galore

And each day, it seems, we are finding yet more,

But are these strange symbols what they seem to be?

Let’s look into the past and perhaps we shall see.

 

It’s 1605 and the whole house is humming;

With numerous labourers going and coming

The great Thomas Sackville to please is their task

So they must obey him, whate’re he should ask.

 

He fervently hopes that King James shall one day

In this beautified dwelling be willing to stay,

But all must be flawless, the peak of perfection,

And naught left to chance for the monarch’s protection.

 

For at night could come witches with evil intent

With spells and with curses on wickedness bent.

So Sackville’s commanded that marks must be made

Convinced that these signs will such beings dissuade.

 

His men will comply, for they’re filled with alarm

And dread a dire fate should the king come to harm.

Thus on panels and doorways the witch marks they leave

So the house will be fit a royal guest to receive.

 

But among them’s a rebel; Luke’s known for his jokes

And he has devised an impertinent hoax.

He scoffs at these witch marks, at sorcery jeers

Deriding his workmates, dismissing their fears.

 

So when evening comes and the labour must cease

Luke lingers awhile and when all is at peace

He takes up his tools, finds a chisel and blade

And in no time at all, many “witch marks” he’s made!

 

There are scratches and circles and lines to be seen

But Luke alone knows what those characters mean.

His sweetheart and sisters’ initials are there,

The circles their faces, the grooves for their hair.

 

His friends see the work and are somewhat impressed.

They’ve seen many witch marks and these are the best.

About their creator there’s much speculation

But Luke remains silent and hides his elation.

 

He’s proud and he’s gleeful, of that there’s no doubt,

Yet anxious as well, lest his mischief’s found out.

He’s beginning to dread that the men are suspicious

When Sackville arrives at a moment propitious!

And seeing the symbols, he’s happy and thrilled

That his wishes have all been so ably fulfilled.

 

I am sure that Luke’s work is at Knole to this day

But which marks are witch marks? Can anyone say?

Clare Fallows, May 2016

 

This is such an inspiring reaction to archaeology and our ongoing conservation project it’s just one of the many reasons we’re so lucky to have our volunteers.

To hear Clare talk about her four decades of service here at Knole click here:

http://www.knolestories.org.uk/content/working-at-knole/volunteers/clare-fallows

 

To find our more about witch marks and medieval graffiti have a look at these links below:

http://www.medieval-graffiti-kent.co.uk/

http://www.knolestories.org.uk/content/working-at-knole/ibk/nathalie-cohen

 

Oh the humidity!

One of the most important elements of conservation is making sure that our collection has the best possible environment to live in. In a house like Knole this is very difficult. It’s a large building with no heating or other environmental control. This means that the house can be at the mercy of the elements. Humidity and temperature rise and fall with the weather with no way for us to control it.

photoCondensation in the Second Painted Stair caused by high humidity (RH)

As part of the conservation project at Knole we will be having special conservation heating installed in the showrooms here. Sadly for our visitors and volunteers this does not necessarily mean that the house will be toasty and warm in winter! The heating will purely be there to control the RH (Relative Humidity) of the rooms. Relative humidity is one of the biggest problems we face here at Knole. When it is too high it causes condensation to build up on vulnerable surfaces, attracts dust and makes a perfect home for mould. It can also create perfect conditions for all sorts of pests such as woodworm and deathwatch beetle. When it is too low it can cause some materials to contract and crack, veneers to lift and glues to fail.

Because of the importance of RH and temperature we have to keep a very careful eye on conditions in the showrooms. If there are particular anomalies such as high RH where it is usually lower we can investigate what has happened. Perhaps there is a leak or a heater has failed. Although we don’t yet have control over the showroom temp/RH we have been able to have some control in some behind the scenes areas at Knole. We have special humidistats in special stores that will react to the Rh in a room and turn on heaters when necessary.

IMAG2818

 Humidistat in the storerooms.

The primary method we use to monitor RH is our Hanwell environmental monitoring system. If you visit Knole you may see the sensors dotted around the galleries.

IMAG2821

Here you can see the Painting Store monitor. It has an LCD display showing you the RH and temperature at the time.

 

Each room has a box and each box is equipped with a transmitter that relays the information it’s gathering to a computer in the office. This then plots a graph that allows us to see trends and patterns in individual spaces.

Within the National Trust we try to aim for an RH level of 40-60%. This represents the amount of water vapour present in air as a percentage of the amount needed for saturation at the same temperature. Because National Trust collections are often so varied and in historic settings there is no perfect RH that is ideal for all materials but this range gives us the best chance.

To make sure we have the most accurate readings possible we also take spot readings on a regular basis. This involves taking a handheld RH/temp monitor into each space and taking an extra reading. This is a good way to make sure we are obtaining accurate information. This is also our primary method of keeping an eye on RH/temp in the part of the house currently undergoing conservation work ready to be opened again next year.

IMAG2815

Here is Zena taking environmental readings in the Ballroom during the conservation work.

Knole suffers with frequent high RH which will be addressed when we have our new conservation heating. Until then we do what we can!