Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Conservation of the royal warship Vasa evaluated

18.10.2010
The conservation of the royal warship Vasa, which sank in Stockholm on her maiden voyage in 1628 and was raised in 1961, has provided a unique insight into how large waterlogged wooden archaeological relics can be preserved for the future, reveals an evaluation of the conservation programme by a researcher at the University of Gothenburg, Sweden.

“I hope that the importance of the conservation of the Vasa will be recognised and provide inspiration and guidance for other attempts to stabilise the dimensions of waterlogged archaeological timber. As conservation projects of this kind are not carried out all the time, my thesis is a way of preserving experience,” says Birgitta Håfors from the Department of Conservation at the University of Gothenburg.


The royal warship Vasa, which sank in Stockholm on her maiden voyage in 1628. Photo: Karolina Kristensson/SMM

After spending her entire career as a chemist working on the conservation of the Vasa, the now retired Håfors has evaluated the conservation programmes using polyethylene glycol (PEG) that was chosen for the vessel’s hull and loose wooden items. At the age of 75, she is now presenting a doctoral thesis on the treatment developed for the warship and used from 1962 until January 1979.

The evaluation focuses particularly on the ability of PEG to prevent or reduce shrinkage during the drying-out of waterlogged archaeological timber, with special emphasis on the oak of the Vasa.

“It turned out that there was often shrinkage during the actual treatment, especially when timber was treated in baths of the preservative solution. This phenomenon is due to water molecules migrating out of the waterlogged timber and into the preservative solution more quickly than the PEG molecules move the other way.”

TEMPERATURE IMPORTANT

In her research, Håfors conducted experiments to find the ideal temperatures and concentrations of the preservative solution to prevent waterlogged wood from shrinking during the actual preservative treatment.

“I soon realised that temperature-raising programmes were unsuitable, as they increased the tendency for water molecules to leave the timber. For the conservation of wood from the Vasa in baths, therefore, a stable temperature was chosen, namely 60°C.

“An increase in the concentration of PEG in the preservative solution also caused water molecules to migrate from the timber into the solution. This could be countered by increasing the concentration more slowly.”

It also emerged that polyglycols with a lower average molecular weight were less inclined to draw water molecules out of the timber. With all of the polyglycols investigated, the lower the molecular weight, the more effectively they prevented shrinkage of the Vasa’s oak. A modified preservative solution for spraying onto the hull was therefore introduced in the early 1970s.

MULTIDISCIPLINARY COLLABORATION

Birgitta Håfors conducted her research as part of the Vasa Museum’s conservation operation, which is a multidisciplinary collaboration between the science and arts faculties at the University of Gothenburg.

The conservation of the Vasa is a case study. The experiments have been performed to provide guidance for the future conservation of the Vasa remains, but the results are probably also relevant for other relics in a similar condition. Each individual species of timber needs to be tested in relation to the preservative solution – oak, pine and lime in the case of the Vasa.

The thesis has been successfully defended.

Further high-resolution press photos of the Vasa can be found on the Vasa Museum website: http://www.vasamuseet.se/bilder

For further information, please contact: 
Birgitta Håfors
Tel.: 
+46 8 758 6836
E-mail: 
birgitta.hafors@gmail.com

Helena Aaberg | idw
Further information:
http://gupea.ub.gu.se/handle/2077/23215
http://www.vasamuseet.se/bilder

More articles from Studies and Analyses:

nachricht WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf

nachricht First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>