Taxidermy Conservation with Simon Moore, M.I.Sci. T., A.C.R.

Recently, I was lucky enough to attend another course with Simon Moore of Natural History Conservation, this time covering the conservation of taxidermy specimens. Having previously participated in the ‘Conservation of Wet Specimens’ I knew I was in for three days of informative, fun and practical training and I wasn’t disappointed.

The course was hosted by Boston Castle, Rotherham, where a wide range of taxidermy specimens with a variety of issues, had been supplied for treatment during the course. Included were birds, mammals and fish in both cased and open display mounts. After an introductory lecture from Simon, we got straight down to practical projects and I chose a fairly raggedy one-legged chaffinch with a number of problems. The cosmetic concerns included minor pest damage, a number of loose and detached feathers and a damaged bill sheath. The structural concerns were two partially detached wings and the aforementioned  missing leg.

          chaffinch before    chaffinch before unsiderside

Although a little daunting as a first project, I felt that this chaffinch was suffering from many of the same issues as the diorama specimens, requiring both structural and cosmetic treatments. Also, as a conservator, I love a good before and after transformation and was curious to see how much of an aesthetic improvement was possible.

Many of the specimens had been in storage for a long time and required a good surface clean. The fragile nature of the chaffinch meant that the specimen needed to be stabilised before any cleaning was undertaken to avoid further damage occurring. I first set about securing the loose and detached feathers, before they became lost or disassociated from their original position, with a tiny dab of neutral PH PVA* adhesive on the lower umbilicus or pointy end of the feather quill.

*Poly-vinyl alcohol adhesive, not to be confused with the white school glue we all know and love as PVA,  poly vinyl acetate, which can yellow and cross-link over time.

The loose leg was secured with a stainless steel pin and spot glued with a little PVA while the wings were similarly adhered to the top edge of the armature wires, which were protruding from the body on either side.

hummingbird before

Whilst the chaffinch was left to one side to dry, I began work on my second project, a very filthy hummingbird. I have tentatively identified this specimen as a Green violetear, either Colibri thalassinus or Colibri cyanotus, in which case the yellow glass eyes are pure fiction, but please correct me if this ID is equally fanciful! Aside from a small missing section of the upper bill sheath, this little hummingbird was structurally sound and only required a good surface clean with cotton swabs and IMS. There are a number of dry cleaning methods for plumage including Document Cleaning Powder (DCP) massaged into the feathers or dry brush and gentle vacuum. The tiny size of the hummingbird made the DCP method impractical but an 80% solution of IMS worked well and revived the iridescence of the plumage very effectively. Any solvent cleaning methods can reduce the natural oils and abrasive methods could be damaging to embrittled feathers so as always, a small test is wise.

cleaning hummingbird

With the hummingbird complete, it was back to the chaffinch. Having the opportunity to make a prosthetic leg for a chaffinch was too good to pass up so I took on the challenge of replicating the existing leg using the conservation grade materials on hand. Using galvanised wire, 10gsm Japanese gampi tissue and more neutral PH PVA, I set about modelling a replacement leg. The extremely fine but robust nature of the Gampi tissue meant that I could essentially papier-mâché skin and claws onto the wire armature. When dry, the Japanese tissue ‘skin’ could be further pared with a scalpel to create as accurate a profile as possible. The new leg was then coloured with acrylic paints and I adhered a couple of the detached downy feathers to the upper thigh to help blend the prosthetic leg into the plumage of the body. Once complete, I filed a point onto the end of the protruding leg wire and pushed it into the body of the chaffinch where it was spot glued with PVA.

Top tip: If the taxidermy form isn’t firm enough to securely hold additional pins or replacement armature wires, a 10% solution of Paraloid B72 can first be injected into the form to consolidate this localised area.

chaffinch leg stages

chffinch after leg   chaffinch after

There were a few finishing touches needed before the chaffinch was complete and these included snipping off a small piece of wire, which was protruding from the beak and causing a cross-bill appearance. I also used more Japanese tissue and PVA to build up the broken lower bill sheath and in-painted the fill with gouache paints. Finally, a little primping and preening improved the raggedy appearance of the feathers and encouraged the dishevelled barbs and barbules to realign. Although I don’t think this chap will be winning beauty contests anytime soon, I was surprised and pleased by the level of transformation possible within a relatively short timescale.

mice before

The third project of the week was this gorgeous case of mice containing a common mouse, dormouse and a wood mouse mounted in a realistic diorama setting. The issues facing this case of specimens were largely cosmetic. The glass was held in place with wide strips of masking tape, the unsightly appearance of which had prevented it from being on display. The back panel of the case had also shrunk slightly and caused a long rip in the left-hand edge of the paper backdrop. The common mouse had a badly kinked tail, which was making contact with the glass, but the other mice appeared to be in good condition. I was keen to tackle some mammalian specimens and also address some of the problems inherent in cases of this type such as timber shrinkage, damaged or discoloured paper backdrops and scenery.

mice glass removal

Top tip: When removing glass, first carefully run a finger around the edge of the rebate to feel for pins that may be holding the glass in place. They are small and easy to miss and will crack the glass if not removed!

After taking out the glass, with the aid of small suction cups, it was apparent that there were a few areas of minor pest damage. The common mouse had a shed larvae case lodged behind one ear and the pest munching had led to some tufts of fur becoming dislodged. The dormouse also had a tuft of loose fur on the neck, possibly also as a result of pest infestation.

mouse pest damage

After first removing the larvae case, I gathered the loose fur into a little swatch and was able to re-adhere it with a tiny dab of PVA. Once dry, the fur swatch could be groomed and blended back into the rest of the neck fur.

Another problem that needed to be addressed was the kinked tail of the common mouse. Fine tissues such as ears and tails can become desiccated and embrittled over time and so attempting to re-shape them can result in serious damage. In order to rehydrate these tissues, we used a product called Bollman’s Ultra Soft which is a soap based relaxer for taxidermy skins. The Bollman’s was applied with a cotton bud to the ears and tails and left overnight to work its magic. The next day the ears were visibly less ‘crispy’ in appearance and the tail far more flexible. After swabbing off any excess Bollman’s, I carefully manipulated the tail into a more life-like position and worked out the major kinks by massaging  and straightening them simultaneously.  Although still a little bent in places, the tail looked better and was no longer jammed up against the front of the glass.

mice tear

While the mice were ‘relaxing’ I could remedy the cosmetic problems in the diorama. Much of the gravel on the floor was no longer adhered and was swilling around the bottom of the case. Similarly, an area of sand in the middle of the habitat had thinned, exposing an odd stripe of bright green paint. These problems could be fixed easily with PVA to re-adhere the gravel and a few bits of loose grass. A little in-painting with gouache paints improved the green paint streak. I was a little more concerned about touching the backdrop as I didn’t want to damage the delicate paper further. The solution turned out to be simpler than I thought however, as a lightweight filler, of the sort used by painter / decorators, could be applied with a spatula to fill the crack without having to touch the paper itself. Once dry, this filler could be coloured to match  with chalk pastels.

mice finished

The finishing touches included ‘dressing’ the fur of the mice, for a more realistic look, by gently backcombing the fur with a soft brush and then lightly brushing back in the right direction. The glass could then be replaced and secured with brown gum tape, which was painted with matt black emulsion. The result was a generally smarter case that could potentially be displayed and stable specimens that had been treated before any major damage or fur loss had occurred.

This three-day course was fascinating and informative and the variety of specimens supplied meant that a range of treatments, in addition to those described here, were covered. Several bats required Japanese tissue repairs on fragile wings, a balding grey squirrel was re-furred and a couple of tiny birds had eye transplants, to name but a few! Many thanks to Simon and our hosts at Boston Castle and also my fellow conservators who were generous in sharing their work and experiences.

A Taste of Taxidermy Part 2..

Day 2 began with the application of the preservative powder onto the inside of the skin  and skull taking care not to get any onto the feathers. The preservative was a proprietary mixture from a taxidermy supplier and although the ingredients weren’t listed, its likely this powder is predominantly borax. At this stage, balls of clay were added to the eye sockets and clay mixed with tow fibre pushed inside the skull cavity. Glass eyes were pushed into the wet clay and the skin could be turned the right way out again.

day-2-step1

At this point it was hard to imagine that the bedraggled clumps of feathers and skin would ever resemble a bird again but the next stage of blow drying with a hair dryer worked wonders. Cotton wool balls were used to temporarily fill the chest cavity and prevent the skin sticking together during blow drying.

day-2-step-2  day-2-step-3

Once dry, the feather regained a lot of their fluffy appearance. The bird was a juvenile so the feathers have a downy texture and seemed more susceptible to damage. The cotton wool was removed and the legs were prepared for wiring. The femurs were each bulked with wood wool bound around the bone with thread to recreate the ‘drumstick’ appearance of the thigh muscle. A sharpened steel wire was then pushed up through the cuts made in the bottom of each foot during tendon removal yesterday. The tops of these wires protruded through the top of the wood wool thigh sections and were left for wiring up later.

day-2-step-4

Next, the wings were wired up. Sharpened steel wires were passed through the length of each humerus and out at the elbow joint. The wires were then anchored in between the bones of the radius and ulna with a few stitches and a small amount of clay to simulate the flesh in this area.

  day-2-step-5day-2-step-6

The next stage was to put the wood wool body form into the skin where the sharpened steel wire running through its centre was pushed up through the top of the skull until the wire protruded through the top of the head. With a bit of adjustment of the skin around the form and skull, the wires from the wings and legs could then be pushed through the body form and cleated to secure them in position. The central incision was then stitched closed.

day-2-step-8

day-2-step-9

Although precision is required at every step, the final stages are where the artistry and an appreciation of natural bird behaviour come into play. The positions of the head, wings and legs are tweaked at this stage and minute adjustments to the eyes and face can be made to give real character and expression to the bird. The feathers and feet can also be rearranged into more realistic positions. The jay was wired onto a temporary base during this phase and pins were used to hold the eyes, wings and tail into place until the specimen has time to dry. The pins stop the skin shrinking and becoming distorted during drying.

day-2-step-10

Finally, a length of gauze was carefully tied around the wings to hold them in position whilst drying and stop the feathers getting disarranged. Once dry, the specimen will be mounted onto a branch and base…images to follow!

So this weekend provided a whistle stop tour of the art of taxidermy and gave me an idea of the processes and equipment involved. Like any craft based practice, a huge amount of time and dedication is necessary to perfect techniques and create a truly lifelike result. This taster session was really inspiring and I plan to attempt the process from start to finish myself in the future and see what happens!

A Taste of Taxidermy Part 1..

In order to better understand the structural instability created by the heavily corroded wires of many of the diorama specimens, it seemed essential to learn the basics of taxidermy as a craft. In a serendipitous fashion, I was recently put in touch with a local taxidermy hobbist who agreed to show me the process. Today we worked on preparing the skin of a young jay that had been frozen for several years after flying into a window.

jay-step-1

After first inserting cotton wool into any offices likely to seep, the initial cut was made with a scalpel along the line of the sternum. From this cut, the skin could be gradually cut away from the muscle taking care not to cause any nicks.

jay-step-2

Upon reaching the thighs, an incision was made through the knee joint allowing the femur or ‘drumstick’ to be removed along with the fleshy muscle. The lower portions of the legs and feet were left attached to the skin. The humerus bones of the wings and associated flesh were similarly removed to be cleaned and reintroduced later. At this point the skinning process continued until the back of the skull was reached and great care was taken to leave the ear holes and eyelids in tact.

jay-step-3

Leaving the skull in situ, the rest of the body and neck were cut away but retained to enable an accurate body print to be made later. Next, the back of the skull was cut away and the brains swabbed out with cotton buds (not a procedure for the squeamish!) The eyeballs and sclerotic plates were removed from each eye socket along with any remaining fleshy material from the skull and wings.

jay-step-4

Once as much of the flesh had been removed as possible, two incisions were made in the bottom of each foot and a hooked tool (a bit like a dental tool) was inserted to pull out the tendons of the legs. The removal of the tendons would create space for wires to be inserted during the mounting phase.

jay-step-5

Using the body and neck portion of the jay for shape and scale, a form was created for the body of the mount by binding wood wool. The shape was approximated roughly at first and loosely bound. This form was then tweaked and tightened through the addition of extra wood wool and further binding. Finally, the form was synched in with stitches at the location where both the wings and legs would be wired on. A central wire was pushed through the body form and this provided the support for the neck and can also be bent into a more lifelike shape later. This wood wool form was then coated in diluted PVA glue and left to one side to dry.

jay-step-6  jay-step-7

After stitching up every orifice with the exception of the eyes , the final steps in stage 1 included rinsing the skin first in cold water followed by the application of a grease solvent. This was applied to the inside of the skin with a toothbrush  taking care to reach all crevices and to go with the direction of the feather quills. The grease solvent was rinsed off and next the skin was soaked in a detergent to clean the feathers and skin. Lastly, the skin and attached skull were rinsed thoroughly in clean water. The skin was then placed in a plastic bag in the fridge to ensure that it stays moist ready for the mounting stage tomorrow.

Although obviously fiddly, the skinning process and washing of the skin appeared quite straight forward in the hands of someone experienced. It seems likely however, that creating a lifelike mount may be somewhat more complicated!

Stay tuned for the results tomorrow!

Testing Taxidermy for Arsenic

The next step in the conservation of the diorama taxidermy will be surface cleaning to remove dust, mould spores and the powdery substances that have accumulated on many of the specimens. There is a high likelihood of the presence of arsenic in any 19th Century taxidermy and as discussed in previous posts, it was known to be a pest deterrent employed in the Suffolk Street shop by Richard Glennon.

Kestrel Arsenic Testing

To determine the potential arsenic content of the diorama specimens, I chose an Osumex heavy metals testing kit which provides quantitative results measured in parts per million (ppm). The test was also relatively inexpensive and easy to administer, both big plusses! Although intended for liquid samples, the Osumex kit below also included very clear directions for making up a test solution from dry ingredients and so this was the method I followed in order to test the powdery substance from the Kestrel pictured above.

Arsenic Test Kit

 A few quick arsenic facts as supplied in the Osumex test kit…..

  • Arsenic is the 20th most abundant element in the periodic table and is most commonly found combined with sulphur and iron ores.
  • Traces of arsenic are found everywhere in water, soil, food, and the air with higher levels present in areas of sedimentary rock like India, China and South America.
  • Studies have determined that levels of arsenic between 50-200 micrograms per litre are enough to cause health concerns.
  • Arsenic poisoning can result in wide ranging symptoms most commonly including vomiting, abdominal pain, diarrhoea and skin lesions.

So with those very unpleasant symptoms in mind, I gathered appropriate personal protection equipment (PPE) and glassware before beginning the test.

PPE    Equipment

In order to make up a test solution, I first scraped the loose white powdery substance from where it had accumulated around the face, feet and underneath the wings. This dry powder was added to a test tube of de-ionised water, stirred vigorously and then left to sit for 24 hours.

Dry powder

Following the instructions supplied with the kit, I first added reagent 1 (with the red cap) to the test tube along with the test solution and stirred it thoroughly. Next, reagent 2 was added (the clear cap) and this was similarly mixed. The final step was to add the third reagent (blue cap) and immediately put on the test tube cap with indicator strip suspended 20mm above the solution which by this time was fizzing away. For 30 minutes the test tube had to be shaken at 5 minute intervals taking care not to splash the solution onto the indicator stick.

Reagent 1   Reagent 2

Finally, after much anticipation, the 30 minutes were up and it was time to dunk the indicator strip into water and compare it to the colour strip. The colour change was not as pronounced as I had thought it might be, indicating that arsenic was present in a quantity of somewhere between 0.1 and 0.25 ppm.

Colour Comparison

Moving forward, it will be extremely important to wear PPE at all times when handling and working with the diorama specimens. The white powder present on the surface of the taxidermy became airborne with very little encouragement and likely contains mould spores as well as traces of arsenic and other chemical used in the preserving of the skins.

The Arsenic Century by James C. Whorton

arsenic century book cover cropped   arsenic century back blurb

Taxidermy historically contained a cocktail of preservatives and pest repelling chemicals including arsenic. After finding an article snippet, dating from 1834, describing Richard Glennon’s particular ingredients of arsenic, sulphur, snuff and alum, I was keen to find out more about arsenic and its deadly reputation. Elizabeth Glennon likely followed the methods of her father in the production of this diorama and so understanding and testing for arsenic will be important for managing the risks associated with the execution of conservation treatments.

Richard Glennon Arsenic Para

Dublin University Magazine, Vol III Jan-June, pp.174, William Curry, Jun and Co., Simpkin and Marshall, London.

 

As well as understanding arsenic and its chemical properties, I was interested to place the diorama within the historical context of its production and perhaps glimpse the world of the Glennon family through the materials they employed. This led me to the book that I felt compelled to share in this book review, ‘The Arsenic Century’ by James C. Whorton.

Through newspaper articles, medical journals, legal records and a host of other contemporary documents, Whorton leads the reader into 19th Century Britain chronicling the rise, the rampage and attempted curbing of the impact of arsenic on all corners of society. Murder, mystery and intrigue are the vehicle for exploring the way in which arsenic came to the fore as a cheap (but rarely cheerful) method of dispatching rodents and troublesome relatives alike. Densely researched and jammed packed with fascinating case studies, Whorton brings countless stories alive with the interspersing of contemporary quotations and his own wry observations.

‘..had to leave his quarters when their vomit began dripping through the ceiling and onto his dining table.’

While accounts of arsenic exploitation by the criminal element undoubtably steal the show, the development of toxicology procedures and legislation in reaction to the arsenic epidemic are no less interesting. The shocking actions of the poisoners described are placed firmly in the context of Victorian Britain where accidental arsenic poisoning was also rife. As Whorton explains, inheritance hungry relatives pale into insignificance in a time where a person was at far more risk of being poisoned by their own wallpaper. Children’s toys, women fashions and even confectionary were risky luxuries in the 19th Century.

‘..he took his complaint to be a bilious derangement.’

Of particular interest in the scope of the diorama project are the accounts of the hazards presented to individuals unlucky enough to work with arsenic in the course of their profession. Taxidermists are one such group mentioned with a detailed account of the miscarriage and incapacitation suffered by the wife of a taxidermist who regularly cleaned his workshop. I wonder what, if any, ailments or ill effects were suffered by the Glennon family taxidermists in the pursuit of their craft.

Not only did I look forward to opportunities to plough through a chapter of The Arsenic Century, I found myself carrying it around the house to squeeze in a paragraph here and there in between other jobs. A non-fiction page turner?! Absolutely! The outlining of arsenic as a chemical element is brief and accessible so anyone looking for more in-depth chemistry will not find it in this book but as a romp through the social historical impact of arsenic across all walks of life, The Arsenic Century is perfect.

The Arsenic Century by James C. Whorton                                                                                                                        Published by Oxford University Press, Great Clarendon Street, Oxford, 2010.                        

ISBN: 978-0-19-957470-4

 

 

The Diorama at Present

It was necessary to completely dismantle the diorama to remove it from a display location with an incredibly low ceiling and doorway scarcely higher than the cabinet was wide. The cabinet was comprised of an internal box within what appeared to be a Regency wardrobe veneered in beautiful Brazilian mahogany. The wardrobe was removed from around the internal box and the loose mouldings and veneers (largely detached due to prolonged display in damp conditions) are currently stored in a flat pack form. The internal cabinet is also drying out in storage as can be seen below.

Inner Diorama Box

The damp which had permeated every element of the diorama was a concern and the paper backdrop in particular was damp to the touch with what appeared to be a layer of white mould across most surfaces. Luckily, the glue adhering the paper backdrop was failing allowing the paper to be removed very easily. Each sheet was around A2 in size and these were numbered in sequence with a view to reinstating the backdrop in the future. A series of really charming pencil drawings were revealed once the paper had been removed but these really deserve a post of their own so stay tuned!

Although the taxidermy specimens themselves did not appear to be showing signs of pest infestation, organic materials are always at risk of pest deterioration, especially since the diorama was displayed in a dark environment with high relative humidity. The taxidermy specimens were individually wrapped first in tissue paper and then several layers of cling film before being frozen for five days to kill off any moths or beasties that may have been lurking.

Freezer Pic

Once the imminent danger of pest attack had been eliminated, the next step in safeguarding the specimens was to reduce their relative humidity (RH). The high RH had already taken its toll with all specimens having suffered extensive wire corrosion and in many cases, corrosion products had burst through the skin of  the legs and feet. It is also likely that the many detached and loose limbs are the result of degraded wire armatures.

In order to lower the humidity of the taxidermy specimens, the cling film was removed and the specimens were placed into a series of sealed plastic storage boxes along with a thermometer/RH meter and boxes of dehumidification crystals (Calcium Chloride Dihydrate). Initially, Art-Sorb engineered silica beads were used as they are a precise and reusable option; a firm favourite with conservators. In this case however, they were not proving particularly effective probably due to the high levels of RH presented coupled with poor re-calibration after a previous usage (in the rainy west of Ireland re-calibrating dehumidification materials is problematic!) For this reason, single use AirWise interior dehumidifier cartridges were used and proved to be a cheap and really successful alternative.

Dehumidifier.jpg

Over a period of three months, the RH within the sealed boxes was monitored and reduced from a sodden 92% to around 50%. At relative humidity levels above 65% organic materials are at risk from mould growth and below 40% feathers in particular can become dehydrated and brittle (Rae 2016). The graph below demonstrates the RH reduction in specimen box 1.

Screen Shot 2016-07-24 at 22.34.03

Currently, the taxidermy specimens are stored on Tyvek® bean bags in sealed plastic  boxes with thermometers/RH meters installed to continue to monitor the environmental storage conditions.

 Harrier Pheasant Quail

Owl Pheasant Francolin   Pheasant Buzzard Grouse

Pheasant and Grouse   Owl Kestrel

Not all of the specimens are pictured. Three of the particularly fragile individuals are awaiting their own boxes, including the pine marten. The golden eagle was too large to fit into standard storage boxes and is firmly attached to its wooden stand, which has been clamped to a solid surface enabling the eagle to remain upright. The feathers of this specimen also seem especially fragile and so it  is at present underneath a polythene tent so as not to further disturb the feathers.

Rae, A. 2016. The conservation of feathers introductory workshop course notes, revised 10 May 2016. 

Feather Conservation – Part 3

One of the highlights of the feather conservation course was having the opportunity to look at and discuss a selection of beautiful feathered artefacts from the collection of the Museum of Archaeology and Anthropology, Cambridge (MAA). Assessing these ethnographic  objects allowed us to put into practice some of the knowledge we had gained about feather structure and the mechanisms that contribute to deterioration. Interpreting the cause of damage can be difficult as natural variation occurs in the condition of feathers, during the life of the bird, and some feathers such as powder down are actually broken down intentionally during preening.

Feather Headdress.jpg

Feathered headdress from the Torres Strait.

This feather headdress  contains feathers that have been decoratively cut leaving them very vulnerable to mechanical damage. The interlocking of the barbs and barbules gives surprising rigidity to the shaft and without this support the shaft can be easily bent by improper storage or handling. We also observed evidence of moth activity in the form of a larvae case.

Red mackaw feathers.jpg

Red macaw feathers from Peru.

The horizontal stripes visible on the macaw feathers could easily be interpreted as natural feather pigmentation but are actually hunger marks developed during the life of the bird. Indicative of periods when food was scarce, the barbules fail to develop properly and result in bands of weakness that can contribute significantly to an overall weakness in the feather structure. Additional black feather tips are adhered to the macaw feather shafts with a black natural resin which is likely to be original to the object. The presence of natural resins such as these can significantly alter which solvents may be safe to use for cleaning and so should be taken into account when developing treatment methodologies.

Green feather necklace.jpg

Feather and basketry necklace from British Guiana (Guyana).

The damage to this feathered necklace was hard to spot at first but evidence of moth activity could be seen around the edge of the basketry where moth larvae had munched holes. With nothing to attach them to the shaft, large sections of the feather vane could easily become  dislodged and lost.

Croc bone headdress

Headdress of cassowary feathers and crocodile osteoderms (the boney deposits underneath crocodile skin) Brazil.

It was a great privilege to be able to get up close and personal with these objects with Allyson on hand to advise and steer the discussion. One issue raised was the importance of  assessing likely causes of damage and discolouration as features inherent to the object may present as deterioration to the untrained eye. The origin and significance of any ethnographic object must also be very sensitively approached as cultural or religious beliefs may preclude the use of certain repair techniques or materials. It is also highly possible that discolouration which could be interpreted as undesirable was actually deposited while the object was in use and so is not only ingrained but also highly significant to its history.

Feather garland.jpg            Wool and feather bunch.jpg

Feathered artefacts from British Columbia.

Keys lessons learnt include:

  • Assess any feathered object extremely carefully and microscopically if possible as areas of weakness may not be immediately obvious or even visible to the naked eye.
  • Some feathers were intended to fade and / or break down during the lifetime of the bird.
  • Feather pigments are many and varied, some are more chemically stable than others.
  • Feathered objects are often composites and so all materials should be taken into account when planning treatments.
  • If in doubt, do nothing! This is just as valid an approach as interventive treatments!

 

Massive thank you’s to Allyson Rae for making feather conservation fun as well as enlightening and to the MAA for allowing us to borrow their stunning objects for the day.

Feather Conservation – Part 2

On day two of feather conservation we concentrated on the structural repair of feathers and it was amazing to see what could be achieved with tweezers, conservation grade adhesives, patience and immense dexterity! (Practice is definitely needed to perfect these techniques but there is huge potential for both structural and aesthetic improvements).

First we needed the badly bent and or broken feathers we cleaned on day one (see part 1!) We would be splinting the breaks in our feathers with a pared down section of shaft from another feather.

Feather splint repair

No1The barbs and barbules were trimmed off to allow access to the shaft.

No2Using a scalpel blade the inside surface of the feather was pared flat and the spongey white interior of the feather scraped out.

No3These steps were repeated with both the front and rear sections of feather shaft and they could then be cut to size allowing at least 10mm of splint either side of the break.

No4 The splints were be adhered.

There were many factors to consider in the execution of this repair technique. As contour feathers are right and left handed, the splint should be made from a shaft that bends in the same direction as the broken one. Choosing a good colour match is also important. The  role of the feathered object should also be taken into account as this technique introduces DNA from another specimen and may not be appropriate for objects that might be subjected to DNA testing in the future. For adhering the splints we tried high concentration solutions of Paraloid B72 and Mowilith 50 for comparison, both dissolved in 50:50 IMS and Acetone. Although Paraloid B72 is the go to choice for many conservators, in this case Mowilith 50 seemed to offer higher initial tack and was also less stringy. Strings of adhesive could be problematic as once on the feather barbs they were very very difficult to remove!

Repair technique number two involved the feather barbs themselves and could be used to improve the appearance of a feather that had lost sections of barbs and barbules either through mechanical damage or pest attack.

Barb repairs

I tried several different types of barb repair which could all prove successful depending on how easily the feather could be accessed and the type of damage. The patch of feather barbs, cut from a different feather, provided the most aesthetically successful repair and with a more delicate touch, the strip of feather barbs could also be very effective. In this case I supported these patches from behind with Japanese tissue but with a very steady hand and carefully applied adhesive, they could have been adhered edge to edge without the need for support on the back. For larger sections or in cases where new DNA should not be introduced, Japanese tissue could be edge joined to the barbs and toned to match with watercolours or acrylic paint.

There are many ways that these repair techniques could be adapted depending on access and the fragility of the feathers being treated. For example, adhesives could be applied, left to cure and then reactivated through the addition of solvents or carefully applied heat. Other materials could also be utilised such as threads or an appropriate textile. The documentation of repaired areas should be carefully planned to ensure that any new feathers introduced are not confused with original material but as with any conservation treatment, materials and techniques must be considered and evaluated on a case by case basis.

Coming soon in part 3, beautiful ethnographic feathered artefacts from the Museum of Archaeology and Anthropology, University of Cambridge.

Feather Conservation – Part 1

Last week I spent a fantastic couple of days on Allyson Rae’s “Conservation of Feathers” course hosted by the Earth Sciences Department of the University of Cambridge. I was hoping to gain insight into the structure of feathers, how to identify specific types of degradation and how best to clean feathers. Given the many and varied states of degradation present amongst the diorama specimens, I was also keen to learn some basic criteria for assessing the fragility of feathers in order to make informed treatment decisions. I was not disappointed!  

I had wondered what factors may be influencing the high levels of degradation in some specimens while others appear in a fairly stable state. We learnt that the high melanin content, responsible for the colouring of brown feathers, is chemically bound to the keratin contained within the feather and so strengthens its structure. The feathers of the brown diorama specimens do superficially appear more stable whereas the iridescent pheasant feathers are quite fragmented and so this was particularly interesting. Some microscopic observations may be the next step towards making comparisons.

Dry Cleaning.jpg                  Groomstick.                                                             Cosmetic sponge.

After learning about the structure of feathers and ethical issues surrounding the treatment of feathered objects, we moved on to dry cleaning techniques. Two of the most effective were cosmetic sponge and Groomstick, although the high tack level of the Groomstick would need to be adjusted for more fragile feather surfaces. 

Next we tried wet cleaning techniques with IMS and water and observed that alcohol based solvents were effective cleaning agents and did not relax the feather structure as dramatically as water. Although potentially detrimental, this effect can sometimes be of benefit as demonstrated below.

Bent shaft.jpg

 Small balls of cotton wool moistened with water were applied locally to the bent shaft until the feather had relaxed back into its natural shape.

In order to further test this technique, we then had a go at straightening out a severely scrunched up feather with miraculous results!    

Screwed up feather.jpg

No1.jpgThe feather had been bent in several places and was fractured on one side.

No2It was placed in a water bath until it began to relax back into shape.

No3 Once straightened the feather could be carefully manipulated into shape.

No4  The feather was then dried with a fan and the barbs gently realigned.

The key message of the day was that it is always best to err on the side of caution as feathers may be far more structurally fragile than they appear and severe damage can occur at a microscopic level with only the slightest of interventions. In life, preen oils are applied by birds to maintain the condition of their feathers and these can be affected by many cleaning treatments. Another important consideration is that some white feathers can yellow over time or may not have been white in the first place therefore not all discolouration can be corrected by cleaning! 

All in all a very informative first day with posts on structural repairs and assessing causes of damage to follow…    

                                      

Conservation Challenges -Feather Degradation

This week I will be attending Allyson Rae’s ‘Conservation of Feathers’ course in Cambridge. I hope to gain a good understanding of which conservation treatments are appropriate to feathers and find out what the options are when the feathers appear seriously degraded. The specimens photographed are fairly representative of the whole flock with damage ranging from heavy soiling, crystalline deposits, broken feathers and friable surfaces.

Impeyan Pheasant Feather Damage.jpg

Impeyan Pheasant also known as the Himalayan Monal (Lophophorus impejanus).

Kestrel Feather Damage.jpg

Kestrel (Falco tinnunculus).

The heavy crystalline deposits visible on the face and chest of the kestrel are likely caused by salts and preservatives used originally in preserving the skin.  In high levels of relative humidity these salts can deliquesce and be drawn to the surface as this moisture evaporates. One such compound commonly used in the 19th century, to prevent pest infestation, was arsenic and white crystalline deposits can be indicative of this.

Interestingly, I came across this snippet from an article in an 1834 issue of the Dublin University Magazine which not only refers to Richard Glennon but also describes this particular treatment. As Elizabeth Glennon would have learnt the craft from her father Richard it is highly likely that these diorama specimens were preserved in the same way.

Richard Glennon Arsenic Para

Dublin University Magazine, Vol III Jan-June, pp.174, William Curry, Jun and Co., Simpkin and Marshall, London.