26/02/2008

Skin processing technology in Eurasian Reindeer cultures by Klokkernes (2007)

Torunn Klokkernes, Skin processing technology in Eurasian Reindeer cultures: a comparative study in material science of Sàmi and Evenk methods – perspectives on deterioration and preservation of museum artefacts, PhD thesis, The Royal Danish Academy of Fine Arts, The School of Conservation (2007)

From the Introduction:
Being comfortably dressed and surviving the cold winters in the Eurasian arctic and sub arctic depends entirely on the clothing you are wearing. Maintaining body heat and being able to work up a sweat without the subsequent formation of icicles on the skin requires a material that insulates, yet breathes, and that is available to the indigenous peoples inhabiting these regions. This has been achieved through many generations by the use of reindeer skin and the ability to transform, through skin processing, raw reindeer skin into comfortable, serviceable, and yet beautiful clothing.
Skin processing in Eurasian reindeer cultures represents an important craft and economic activity essentially related to the women
s sphere. Skin processing has not been thoroughly described in the available literature, and the knowledge is not easily accessible from the artefacts themselves. As this project was taking shape, the importance of understanding the practical methodology of skin processing was recognized as a significant part of the study. In order to obtain this information, people who were familiar with the technology of skin and fur processing and who were willing to share their knowledge were contacted, mainly through local museum institutions. Their knowledge is interesting, not only from a technological or preservation point of view but also from a cultural and social point of view, as it conveys the history of past generations.

22/02/2008

"Lipid fraction in historical parchments: a potential role in degradation?" by Ghioni et al (2005)

Ghioni, G.; Hiller, J. C.; Kennedy, C. J.; Aliev, A. E.; Odlyha, M.; Boulton, M.; Wess, T. J.; "Evidence of a distinct lipid fraction in historical parchments: a potencial role in degradation?", Journal of Lipid Research 46 (2005) 2726 - 2734
doi:10.1194/jlr.M500331-JLR200


Abstract:
Parchment, a biologically based material obtained from the processed hides of animals such as cattle and sheep, has been used for millennia as a writing medium. Although numerous studies have concentrated on the structure and degradation of collagen within parchment, little attention has been paid to noncollagenous components, such as lipids. In this study, we present the results of biochemical and structural analyses of historical and newly manufactured parchment to examine the potential role that lipid plays in parchment stability. The lipid fraction extracted from the parchments displayed different fatty acid compositions between historical and reference materials. Gas chromatography, small-angle X-ray scattering, and solid-state NMR were used to identify and investigate the lipid fraction from parchment samples and to study its contribution to collagen structure and degradation. We hypothesize that the origin of this lipid fraction is either intrinsic, attributable to incomplete fat removal in the manufacturing process, or extrinsic, attributable to microbiological attack on the proteinaceous component of parchments. Furthermore, we consider that the possible formation of protein-lipid complexes in parchment over the course of oxidative degradation may be mediated by reactive oxygen species formed by lipid peroxidation.

17/02/2008

"Ricientes avances en conservación de objectos de cuero" por Álvarez (2005)

Álvarez, Gerardo M. G.; “Ricientes avances en conservación de objetos de cuero”, Museos.es, n.º1 (2005) 80-87

Resumen: Se presenta una visión de la problemática general de la conservación y restauración de objetos de cuero desde el punto de vista de la permanencia del material. Una somera revisión bibliográfica nos acerca a los desarrollos realizados en este campo desde la década de 1990. Por último se presenta una discusión de los datos obtenidos en los últimos estudios que he realizado centrados en las características hidrodinámicas del cuero, su relación con el deterioro y las conclusiones que podemos establecer de cara a la conservación de este material.

Abstract: An overview of the general problems associated with conserving and restoring leather objects from the point of view of the permanence of the material. A summary bibliographic review gives us an idea of the advances made in this field since the nineties. Finally, there is a discussion of the data obtained from the most recent studies which have focused on the hydrodynamic characteristics of leather, their role in deterioration and the conclusions that can be drawn in terms of the conservation of this material.

15/02/2008

Tanning in Fes, Morocco by National Geographic (2006)

No processo antigo e tradicional de curtume de peles, as operações de pré-curtimenta caracterizavam-se por serem trabalhos muito pouco agradáveis aos sentidos mas, no entanto, fundamentais para a obtenção de um bom cabedal. Em Marrocos, na cidade de Fez, é ainda possível testemunhar as técnicas manuais da lavagem das peles, do caleiro, descarna, desencalagem e purga, esta última com dejectos de animais. A purga (ou lixo), actualmente efectuada com enzimas, é uma operação essencial para abrir a estrutura de fibras de colagénio da pele e é utilizada na preparação de cabedais macios.
Este curto vídeo de 2006 produzido para a National Geographic mostra-nos, poupando-nos o olfacto de uma experiência desagradável, como se preparava no passado uma pele para receber a curtimenta.

This video is a travel back to the Middle Ages of the tanning process. If you play it, you will watch the manual preparation of skins before tanning still in use in Fes. In particular, you will watch puering operation, a noisome operation which uses pigeon dung, employed mainly for sheep and lamb skins.


11/02/2008

Recent preoccupations concerning textiles, leather, legislation. Post-prints relating to leather (2007)

Recent preoccupations concerning textiles, leather, legislation: post-prints related to leather / Préoccupations récentes concernant le textile, le cuir et la législation: publication concernant le cuir, Post-prints of the Interim Meeting held in Athens, 21-24th April 2004 / Réunion intermédiaire Athènes, 21-24 Avril 2004; ICOM-CC Working Group “Leather and Related Materials”/Groupe de Travail “Cuir et Matériaux Associés” (2007)

Thanks to the work done by Theo Sturge, ICOM-CC Leather Group Coordinators and all the contributors Athens Meeting post-prints are now published. It contains 22 papers on a variety of aspects of leather conservation and is available on http://www.lulu.com/content/1644345 . The printed book is available "at cost" plus postage or it can be downloaded free as a full colour PDF file.

08/02/2008

"Arsenic in taxidermy collections" by Marte et al (2006)

Marte, F.; Péquignot, A.; Von Endt, D.; “Arsenic in taxidermy collections: history, detection and management”, Collection Forum 21 (1–2) (2006) 143–150

Abstract:  
An historical review of taxidermy treatments shows that arsenic has been used in the preparation and conservation of specimens from the 18th century until recent times. Two spot tests for arsenic detection have been tested and compared: the Weber’s test and a kit developed by Macherey-Nagel. Stuffed birds from the Museum National d’Histoire Naturelle, Paris and standard arsenical solutions were spot tested and results compared with those using Inductively Coupled Plasma Spectrometry (ICPMS). The spot tests compared well to the results using expensive equipment, are freely available, inexpensive and provide an adequate level of detection down to 20 ppm. All specimens should be monitored even those that test negative first time round. Institutions should be responsible for monitoring levels of arsenic in collections, use appropriate protection when handling all specimens and regularly update health and safety records.

And in the same number:
Péquignot, A.; Tumosa, Ch.;Von Endt, D.; “The effects of tanning and fixing processes on the properties of taxidermy skins”, Collection Forum 21 (1–2) (2006) 133–142
PDF

Abstract: 
The effect of different tanning and fixing processes on the mechanical properties of taxidermy skins was investigated using a screw driven tensile machine. Tanning treatments were potash alum powder, salt and a bath (salt, potash alum, and water) used at the Museum National d’Histoire Naturelle in Paris. Fixing was with formalin or alcohols (methanol, ethanol, and 2-propanol). Stress vs strain plots using results from air-dried skin as control show that air dried skins are least flexible, squirrel skins are significantly stiffer than deer skins but that all the skins tested show elastic properties, except skins fixed in formalin. The MNHN bath produces stronger and more flexible treatments than using potash alum or salt powder on their own. There were no significant differences between ethanol and 2-propanol treated skins at similar concentrations but methanol, ethanol and 2-propanol have increasing flexibility. Increasing ethanol concentration makes the skin more flexible. Even small amounts of formalin increase flexibility and large amounts of formalin are not needed to make a useful skin for taxidermy. Differences of bonding between collagen fibbers in the skins account for the differing mechanical properties and suggest ethanol is better than formaldehyde for future preparations. Knowledge of preparation technique is vital when considering future conservation strategies.

03/02/2008

The naturalist's guide in collecting and preserving objects of natural history by Maynard (1887)

Maynard, C. J.; The naturalist's guide in collecting and preserving objects of natural history, Cupples and Hund Publishers, Boston (1887)

Table of contents:
1. Collecting and preserving birds
2. Collecting and preserving mammals
3. Collecting and preserving insects for the cabinet
4. Collecting and preserving fishes and reptiles
5. Miscellaneous collections


And I reproduce here an interesting and curious ad printed in the first page of this book:



And one more (here partially reproduced):

The art of taxidermy and taxidermy collections

Taxidermia (do grego taxis + derma que significa "dar forma à pele") é a arte de montar (empalhar) ou reproduzir animais para estudo ou exposição. Em muitos casos, a pele (incluíndo pêlo, penas ou escamas) dos espécimes é preservada sobre estruturas de suporte. Estes espécimes podem ser encontrados em colecções de história natural.

Taxidermy (greek taxis + derma) is the art of mounting or reproducing animals for display or for other sources of study.
Taxidermy can also be defined as practice of creating lifelike representations of animals by using their prepared skins and various supporting structures. Taxidermy began with the ancient custom of keeping trophies of the hunt. Beginning in the 18th century, a growing interest in natural history resulted in collections and exhibits of birds, beasts and curiosities. Chemically preserving skins, hair, and feathers made it possible to recreate the appearance of live animals by stuffing the sewed-up skin with straw or hay. (From Britannica Concise Encyclopedia)


More information regarding taxidermy collections can be found at:
Working group on "The art of taxidermy and its cultural heritage importance" of ICOM-NATHIST (ICOM International Committe for Museums and Collections of Natural History) website or newsletters:
"Working group on the art of taxidermy and its cultural heritage importance", ICOM NATHIST Newsletter 15 (2006)
"Case studies- taxidermy and habitat groups", ICOM NATHIST Newsletter 17 (2006)

01/02/2008

Bookbinding and the care of books by Cockerell (1906)

Cockerell, D.; Bookbinding and the care of books: a handbook for amateurs, bookbinders & librarians, D. Appleton, New York (1906)