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Navigating conservation strategies: linking material research on alum-treated wood from the Oseberg collection to conservation decisions
Susan Braovac ORCID: orcid.org/0000-0002-3557-91341,
Caitlin M. A. McQueen1,
Malin Sahlstedt1 nAff3,
Hartmut Kutzke1,
Jeannette J. Łucejko2 &
Torunn Klokkernes1
From the mid-1800s to the late 1950s, conservation by alum salts (aluminum potassium sulfate dodecahydrate)—with some variations—was a routine method for treating highly deteriorated waterlogged archaeological wood in many countries, especially in Scandinavia. It was eventually replaced by newer methods in the 1960s, such as that using polyethylene glycol. Accordingly, the signs of deterioration in such collections and the reasons behind them are not well known among current preservation specialists. The research in the Saving Oseberg project (2014–2019) has shed light on the consequences of this treatment and reasons behind the severe deterioration observed today in many objects of the Oseberg Viking Age wooden finds, which were conserved in the early 1900s. Saving Oseberg aims to provide research-based recommendations for the future preservation of the finds, and as such, a large part of the project is aimed at improving our understanding of this complex material. Here the consequences of the method are summarized, drawing on the research to date. Chemical analyses of the Oseberg wood showed its current condition to be highly degraded: little polysaccharide content is left and the lignin is significantly oxidized and extensively depolymerized. The conservation implications are also discussed.
Museum collections conserved by discontinued treatments may require specialized knowledge to enable their proper care. This is especially true in cases where older conservation treatments are the cause of unacceptable damage, sometimes only revealed after a great elapse of time. At the Museum of Cultural History (KHM) it took almost 100 years for observable damage, such as new cracks, to manifest itself on a collection of archaeological wooden objects which were conserved in the early 1900s by a once widely used method which is now obsolete. This method used alum salts (potassium aluminum sulfate dodecahydrate, KAl(SO4)2·12H2O) to preserve highly degraded archaeological waterlogged wood. It was actively in use from the mid-1800s to the 1950s, especially in Scandinavia [1,2,3,4]. Many collections may therefore have alum-treated wooden objects. However, due to the fact that this method is no longer in use and knowledge about it is limited, preservation professionals may not be aware of how to identify alum-treated wood nor understand reasons behind the observed damage.
At KHM, alum salts were used to conserve a significant portion of the wooden objects from the Oseberg mound, a Viking Age ship burial for two women constructed in 834 AD, located near Tønsberg, Norway and excavated in 1904 [5]. This collection represents one of the richest, most complete collections of Viking Age wooden objects in the world: alongside textiles and metal objects, lay ornately carved wooden objects such as a ceremonial wagon, three ceremonial sleds, animal head posts and hundreds of everyday artefacts [6]. The find is exhibited at the Viking Ship Museum in Oslo.Footnote 1
We now know that the alum treatment has caused both chemical and mechanical degradation of the wood. To chemically and physically stabilize alum-treated objects from the Oseberg find—which present challenges in terms of variability in condition, size and in degree of restoration—a combination of preventive and invasive reconservation approaches is needed. However, successful preservation strategies can only be designed if the causes of the observed damage are understood. Few details about the alum treatment method are recorded in archival and published sources, and previous research did not investigate the material's chemical properties [4, 7]. For this reason, the Alum Research Project (2007–2013) and later the Saving Oseberg (SO) research project (2014–2019) were established at KHM. Initially, research was directed towards investigating chemical and physical properties of the material in order to gain a better understanding of the reasons behind the observed deterioration. Currently, we continue to investigate the chemical properties but also are investigating reconservation methods. Although much of this research has been published, the newly gained material knowledge has not yet been brought together into a broader preservation perspective. This paper summarizes what we know thus far about the material and discusses how it impacts the main preservation issues, using the Oseberg collection as a case study. The information presented here about alum-treated wood from the Oseberg finds adds to previous works [1, 4, 7] and provides means to identify and interpret the signs of degradation in alum-treated wood in other collections.
Condition of the Oseberg finds upon excavation
Approximately 5000 tons of turf and large stones sealed the burial mound. This load had caused compression of the blue clay upon which the ship rested, crushing the grave contents [6, 8]. The large amount of organic material recovered from the Oseberg mound is attributed to relatively stable water levels released from the blue clay mass lining the base of the mound [8]. Water, together with the turf cover, created an almost anoxic state favouring the slow action of bacterial decay. The recovered waterlogged wooden objects were deteriorated to varying degrees in the burial mound, roughly following wood genus.
The oak ship and objects made of oak, ash, yew and pine, were in relatively good condition and could be air dried. However, a large portion of the objects were made from various hardwoods, such as maple, alder, birch and possibly beech, and were highly deteriorated upon recovery. These woods needed to be conserved before drying. Prior to their transport to Oslo, all wooden objects, except for the ship fragments, were surface-cleaned on-site and packed in wet moss and burlap. Upon their arrival, they were placed into zinc containers filled with water, to which a small amount of the biocide sublimate (mercuric chloride, HgCl2) had been added [6].
Finds treated with alum
In the 1800s treatments for waterlogged archaeological wood were based on the application of coatings using various solvents, oils and waxes which did not lend support to the wood's cellular structure in severely deteriorated objects [9]. In the late 1850s, the recovery of vast amounts of highly degraded waterlogged archaeological wood from the Vimose find in Denmark stimulated research into alternative conservation treatments at the National Museum of Denmark. In 1861 Christian Frederik Herbst, archaeologist at the National Museum of Denmark published—simultaneously with C.A. Speerschneider of Glücksburg Castle, Germany—the first known accounts of treatment with alum salts, which they had developed independently [10, 11].
After ca. 1910, glycerol appears to have become a standard addition to the alum-treatment despite the fact that the object became extremely sensitive to ambient relative humidity due to the hygroscopic glycerol, often resulting in its complete destruction within only a few decades [1]. Glycerol was not used on the Oseberg finds, even though it was being experimented with in 1904.
Professor Gabriel Gustafson, who led the Oseberg excavations on behalf of the University Museum of Antiquities (now KHM), learned of the alum treatment from a study visit to the National Museum of Denmark in the Fall of 1904. Ideally a conservation method should preserve surface carvings and maintain the shape of fragments upon drying so that they could be puzzled together into whole objects. This required surfaces which were possible to glue together. In light of the difficulties in securing funds for the recovery and preservation of this find, conservation should also be affordable and efficient. The only method found to fulfill the above criteria was that which used alum salts (Fig. 1) [6]. It was also likely seen as a reliable treatment as it had been in use for almost 50 years.Footnote 2
Testing the alum-treatment on an object where the four pieces fit together, ca. 1905. The right piece was alum-treated. The two pieces in the centre were waterlogged. The left piece was the result of air-drying [6]
The conservation and restoration of the Oseberg finds took place between 1905 and ca. 1912 and involved approximately 400 objects (and thousands of fragments). Approximately 45% of the finds were made of wood, and of these about 25% were treated with alum salts (ca. 12% of the collection). Unique objects such as the ceremonial sleds and saddle were treated with alum salts.
The principle behind the method took advantage of alum salt's high solubility in hot water (ca. 90 °C), and its low solubility in cold water. The waterlogged wood was impregnated with dissolved salts in the hot concentrated solutions, which upon removal from the bath would cool, causing the salts to recrystallize immediately, retaining the shape of the wooden object or fragment. At this point, surfaces had to be thoroughly washed with hot water to prevent the formation of salt deposits.
Most satisfactory results were obtained on wood that was evenly degraded from surface to core, that is, woods one could 'almost stick one's fingers through'.Footnote 3 The surviving laboratory journal gives insight into the treatment process for some objects [13]. Treatment times ranged from 2 to 36 h. For objects greater than one centimeter in thickness and for those in very poor condition, the average impregnation time was 24 h. The exact concentration of alum salt was not noted in the laboratory journal, but in the excavation publication, concentrations of two to four parts alum to one part water by weight are mentioned [6]. Higher concentrations were used on more deteriorated finds. In all, three barrels (tønder) of alum were used,Footnote 4 which roughly corresponded to 139 L. Decorative metal nails were removed from most objects before treatment and later replaced.
After impregnation with alum, the fragments were air-dried to constant weight. At this point many of the fragments were impregnated with boiled linseed oil to improve their resilience, since the alum method resulted in wood that was as 'brittle as glass'.Footnote 5 For smaller objects, linseed oil was applied by brush or by soaking the fragment in it until it was saturated. For larger objects, holes were drilled to improve the penetration. The linseed oil was first thinned with turpentine; successive coats were applied with increasing linseed oil concentrations.
The reconstruction of the fragments into objects involved extensive use of modern materials (Fig. 2). After drying, treated fragments were glued with carpenter's glue (animal-based) or screwed into wooden planks. A gypsum-based puttyFootnote 6 filled areas of loss [6], confirmed by recent infrared analyses.Footnote 7 A shellac mixture, possibly similar to that described by Bojesen-Koefoed and Stief [15], was used as an adhesive on at least one of the sleds.
Each sled is reconstructed from thousands of fragments. Here the Fourth sled is shown during restoration by conservator Paul Johannessen sometime before 1912. Photo: KHM
X-radiographs taken in the early 2000s revealed extensive usage of screws, pins and metal parts (Fig. 3). In some cases, the metal was fitted flush with the surface of the object by cutting away the wood. Reconstructed objects were coated with a matte varnish (mattlakk) to reduce the shine produced by the linseed oil and to protect the wood from the 'influence of (moisture in the) air' Footnote 8 [6].Footnote 9 An epoxy-based coating was applied during the 1950s as reported by Rosenkvist [16]. Its composition was confirmed by infrared analyses.Footnote 10
Detail of the Fourth sled. The X-ray (top) shows the extensive use of metals in its reconstruction. X-ray image: Nancy Child (NL), Susan Braovac (SB), Ragnar Løchen (RL); Photo: KHM; Collage: Nadine Huth (NH)
Highly deteriorated wood not treated with alum
Seven objects bore very finely carved surfaces. One was treated with alum, but it resulted in significantly blurred surface details. Therefore the remaining six objects were kept immersed in water until 1955 or 1956, when a suitable conservation method was found using tertiary butanol and freeze drying [17]. During the 1940s one of the tanks sprung a leak, destroying the animal head post it contained. However, it was saved and has been kept in storage ever since. This object provided a reference sample for chemical analyses, as its degree of degradation during burial was the closest match to those woods which had undergone the alum-treatment. The consistency of the wood from this object was typical for that of degraded archaeological wood, that is, it was weak but not powdery.
Consequences of alum treatment—results of current research
The following section summarizes this material's most important aspects based on research so far, which includes chemical characterization of the wood, identification of inorganic compounds present, investigations on alum-treated wood's cellular morphology and its interaction with moisture. These topics contributed to a better understanding of the current chemical and physical state of preservation of the wood and thus greater insight into the types of degradation reactions that have occurred/are occurring therein.
Analytical methods used
Various analytical techniques were used to characterize alum-treated samples. Full descriptions of methods are given in the accompanying references in the text. For clarity, results which are not published are indicated in footnotes. Wood structure was investigated using conventional light microscopy, X-radiography, X-ray tomographic microscopy and scanning electron microscopy (SEM). Non-invasive methods such as colour and pH measurements were also carried out, using a spectrophotometer and pH strips, respectively. The chemical composition of the wood fraction was investigated using an array of complementary methods: pyrolysis gas chromatography mass spectrometry (Py(HMDS)-GC/MS), in the presence of derivatizing agent hexamethyl disilazane (HMDS), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), infrared spectroscopy using synchrotron radiation (SR-IR), different nuclear magnetic resonance (NMR) methods, and gel permeation chromatography (GPC).
To identify and quantify inorganic elements, SEM coupled with energy dispersive spectroscopy (SEM–EDS) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) were used, respectively. Quantification of water-soluble ions was undertaken with ion chromatography (IC). Powder X-ray diffraction and infrared and Raman spectroscopy were used to identify inorganic compounds.
Alum salt
Alum salts are hard, glossy, transparent or white crystals often large enough to see by eye or at low magnifications (Fig. 4). In written sources about the treatment, only potassium alum is mentioned, KAl(SO4)2·12H2O. However our group has found that in some cases objects also contain substantial amounts of ammonium alum, NH4Al(SO4)2·12H2O [18]. Ammonium alum was often sold mixed with potassium alum [19]. Both salts have similar physical properties (melting point, solubility, density) [20].
Stereomicrosope image of alum crystals in wood. The crack has formed along the alum-rich and alum-poor boundary. Photo: SB
Alum salt distribution was studied at both macroscopic levels and at higher resolutions [21]. Visual examination and conventional X-radiographs of recently broken fragments from storage showed that alum (and linseed oil, where it was used) penetrated only to a depth of about 5 mm across the grain and 5 cm along the grain of the wood (Fig. 4, see also Fig. 6). X-ray tomographic microscopy images show alum crystals in both fibres and vessel elements. It is an uneven, patchy distribution, even along the length of a single vessel (Fig. 5). These images also show high density regions in alum-treated woods from Oseberg, due to inorganic deposits which are not alum (Fig. 5a, c). It is uncertain whether these inorganic compounds derive from post-conservation chemical changes in the alum salt or were deposited as different types of salts during the conservation treatment.
X-ray tomographic images of an Oseberg sample showing distribution of alum salts in the three main directions: transverse (a), tangential (b) and radial (c). Brighter regions (circled) indicate another inorganic compound likely derived from the alum treatment. Images show alum's patchy longitudinal distribution (b, c). The bar shows 50 μm. Acquired at the TOMCAT beamline, Paul Scherrer Institute (PSI), Switzerland by HK, MC and SB. Rendered by SB
Source of acidity
pH measurements show a range of values in alum-treated woods, between pH 1 to pH 4.5, with values generally below pH 2.5, while untreated archaeological woods from Oseberg have a pH of about 4.5 [22]. It turns out that the source of acidity is the alum treatment itself [12]. Reaction scheme [1] shows solution behavior at room temperature. Heating potassium alum baths to 90 °C (reaction scheme [2]) causes a significant reduction in solution pH within a few hours (from pH 3.5 to 2), due to the precipitation of small amounts of alunite (KAl3(SO4)2(OH)6) which only forms in the heated solutions. An excess of sulfur relative to aluminum content has been found in wood samples analyzed by ICP-OES. Ion chromatography showed that most of the sulfur is present as sulfates [21], supporting the hypothesis that acidic sulfate species were absorbed during treatment.
$$2{\text{KAl}}\left( {{\text{SO}}_{4} } \right)_{2} + 2{\text{H}}_{2} {\text{O}} \rightleftharpoons 2 {\text{K}}^{ + } + {\text{Al}}\left( {\text{OH}} \right)^{2 + } + {\text{Al}}\left( {{\text{SO}}_{4} } \right)^{1 + } + {\text{H}}_{3} {\text{O}}^{ + } + 3{\text{SO}}_{4}^{2 - } \quad {\text{pH = 3}} . 5 ,\;{\text{RT}}$$
$$3{\text{KAl}}\left( {{\text{SO}}_{4} } \right)_{2} + 12{\text{H}}_{2} {\text{O}} \to {\text{KAl}}_{3} \left( {{\text{SO}}_{4} } \right)_{2} \left( {{\text{OH}}_{6}} \right)_{\downarrow} + 2{\text{K}}^{ + }_{{({\text{aq}})}} + 4{{\text{SO}}_{4}}^{2 - }_{({\text{aq}})} + 6{\text{H}}_{2} {\text{O}}^{ + } \quad {\text{pH}} = 2,\; 9 0\;^\circ {\text{C}}$$
Contrarily, heated solutions of ammonium alum maintain a constant pH of 3 without precipitate formation.Footnote 11 We have found both types of alum in different objects analyzed, one of which is reported in Łucejko et al. [18].
Mechanical damage
Mechanical damage can be traced back to the alum-treatment. Strength tests carried out in 2002 on alum-conserved wood without linseed oil, revealed that samples retain approximately 2–5% of the bending strength and 6–8% of the modulus of elasticity of fresh wood [23]. This is comparable to crisp-bread, whose strength was also measured in the same study. Due to its salt content, the density of alum-treated wood is generally similar or even greater than the density of fresh wood.
The incomplete penetration of alum salts resulted in a wooden object with a thin alum-rich outer layer surrounding an un-conserved wooden core, in agreement with Christensen's descriptions of alum-treated objects at the National Museum of Denmark [1]. Drying stresses thus caused the inner core to shrink while the outer part remained intact, resulting in cracks that are both transverse (across the grain of the wood) and longitudinal, especially in boundary regions where the alum-rich outer layer meets the un-conserved core (Fig. 6, see also Fig. 4). New cracks observed on the surface in many of the alum-conserved objects are likely extensions of the inner cracks which have been allowed to propagate due to inadequate physical support.
a Fragment from the Oseberg find, recently broken. The alum-rich layer, ca. 5 mm thick, surrounds an inner alum-poor core. Inner voids are also evident ('V'). Tension between the alum-rich and alum-poor boundary regions has resulted in crack formation (arrow). b X-ray image of the same fragment revealing minimal alum penetration across the grain, and better penetration along the grain (ca. 5 cm). Transverse inner cracks have been formed by drying stresses in the alum-poor core (arrows). These are not visible on the surface, shown in the photograph (c). Xray and photo SB
It is also common to observe longitudinal collapse of wood cells below the surface, due to incomplete penetration and/or osmotic shock arising from the highly concentrated alum solutions used during treatment. Areas of longitudinal collapse appear as voids in cross-sectional breaks of larger fragments, as shown in Fig. 7. Voids can be very small or over 1 cm in diameter and several cm in length. Characteristic surface undulations in a fragment are indications that it may have hollow areas. This is seen very clearly in the wheels of the wagon (Fig. 8). Obviously such areas on an object are extremely vulnerable to damage.
Collapsed areas of wood, formed during treatment, are visible in this computer tomographic image taken of the Saddle. The red squares show two collapsed areas. Alum salts and the linseed oil have penetrated minimally (A + L), while the varnish is the bright layer on the surface. Fill material (F) and screws originate from restoration after conservation. Acquired by Jan Bill and Sentrum Røntgeninstitutt AS
(Taken from Vike [24])
a Undulations on the surface of alum-treated objects are signs that large voids are present below the surface (arrows). b A recent X-ray image showing a part of another wheel where dark areas (arrows) are voids formed during treatment
New breaks are also related to the post-conservation restoration work. In some objects, cracks are present in areas adjacent to metal brackets, and screws have lost their grip in some cases. X-rays show some metal pins holding fragments are corroding (Fig. 9). The putty has shrunken, sometimes tearing the wood with it.
X-ray image detail of Gustafson's sled, showing corroded metal pins used to hold fragments together in the reconstruction. Acquired by SB, NC, Torunn Klokkernes (TK)
Wood colour and wood morphology
Inside new breaks in displayed objects and in wooden fragments retrieved from storage, we often find that the wood had a powdery consistency with little structural integrity. Wood colour ranges from pale beige to dark brown (Fig. 10). The darkest woods are consistently more friable and lose material, even with careful handling [22]. In the stereomicroscope it is possible to see that alum-treated woods are mainly of diffuse-porous types. Wood identity as given in the publication of the find is not always reliable [6].Footnote 12 Today, it is not possible to definitely verify wood type for many objects since their present condition is so deteriorated that it is difficult to obtain coherent samples for study under the light microscope. Light microscopy is used to identify woods where more invasive sampling is possible. So far, microscopic examination has identified diffuse-porous hardwoods such as birch (Betula sp.), maple (Acer sp.) and alder (Alnus sp.), and less commonly, ring-porous hardwoods such as oak (Quercus sp.).
Different colours of alum-treated wood and corresponding pH values. Photo: SB
SEM images show that the secondary cell walls are highly degraded: they are either missing or completely detached and shrunken. The middle lamella is the main part of the cell wall system that survived and the resilient lignin-rich cell corners also underwent deterioration in some samples. Areas of localized collapse/shrinkage were evident in some cells which did not contain alum. It was not possible to discern the differences observed in macroscopic condition in SEM images. That is, wooden fragments which have clear differences in their structural integrities have similar cell structures. X-ray tomographic microscopy showed that more degraded wood had lower attenuation of the X-ray beam, indicating significant mass loss (Fig. 11). In the worst cases the wood was largely held together by alum salts (Fig. 12).
Both images were taken at the same X-ray exposure. a Fresh birch; b an Oseberg sample where alum had been removed and the wood freeze dried. The greater attenuation in the fresh birch (the image is brighter) indicates a greater wood density, and hence better state of preservation. The bar shows 50 μm. Acquired at TOMCAT, PSI by Hartmut Kutzke (HK), Mikkel Christensen (MC) and SB
X-ray tomographic image of Oseberg 185-5. The wood cells are shown by thin grey lines. Alum salts (white/grey) dominate the image. The presence of a denser compound is circled. The bar shows 50 μm. Acquired at TOMCAT, PSI, by HK, MC and SB
Chemical composition of wood and inorganic compounds identified
The most pertinent analytical results are summarized below.
Chemical composition of wood
To investigate the extent of degradation caused by the alum treatment, alum-treated Oseberg wood (without linseed oil) was compared to a sample taken from the untreated, destroyed animal head post mentioned earlier and from an oak sample from the well-preserved Oseberg ship. Sound woods and waterlogged archaeological woods were also analyzed [21, 26, 27]. Here, the results from analytical pyrolysis (Py(HMDS)-GC/MS) will be highlighted; it is a semi-quantitative method which allows comparison of relative amounts (abundances) of pyrolysis products from different samples.
The most significant feature distinguishing Oseberg alum-treated woods from those which were not treated with alum, observed after analysis by Py(HMDS)-GC/MS, was the low content of holocellulose (the term for combined cellulose and hemicellulose), ca. 3–20% relative abundance. What is mainly left is lignin, up to 97% relative abundance. Analyses of wood from Oseberg not treated with alum and of recently excavated waterlogged archaeological wood showed holocellulose contents ranging from 15 to 68% and lignin from 32 to 85% relative abundances, depending on their degree of degradation. These values resemble those for freshly excavated waterlogged archaeological woods from other sites analyzed by analytical pyrolysis, where relative abundances ranged from 14 to 61% for holocellulose and 34 to 80% for lignin [28, 29]. The chemical composition of the wood fraction from alum-treated woods is thus very different from untreated archaeological woods. Sound woods had relative abundances ranging between 58 and 78% for holocellulose and from 21 to 42% for lignin [26].
These differences become even more apparent when pyrolysis products are classified into sub-groups. For instance, lignin oxidation pyrolysis products in Oseberg woods are present in up to 80% relative abundance of total lignin. Oxidation products were mainly composed of carbonyl compounds, such as vanillin and syringaldehyde and carboxylic acids, comprised of syringic and vanillic acids as well as small amounts of para-hydroxy benzoic acid in some samples. In sound wood, lignin oxidation products make up 5–7% of total lignin [27]. Two-dimensional NMR and GPC [30] confirmed the high extent of lignin depolymerization inferred by analytical pyrolysis and ATR-FTIR studies [21, 27].
Likewise, pyrolysis products derived from holocellulose can be divided into sub-categories. In alum-treated woods, polysaccharides formed during pyrolysis are mainly anhydrosugars, which may be considered an index of holocellulose degradation. In sound woods, the most abundant holocellulose category is made up of cyclopentenones such as 3-hydroxy-2-hydroxymethyl-2-cyclopentenone, and E-2,3-dihydroxy-cyclopent-2-enone [31, 32]. The second most abundant group is composed of anhydrosugars which are mainly represented by levoglucosan (1,6-anhydro-beta-d-glucopyranose).
Anhydrosugars are present in different trimethylsilyl (TMS) derivative forms: tri-TMS, di-TMS and mono-TMS when the pyrolysis is carried out in the presence of HMDS. The more depolymerized the cellulose and hemicellulose networks, the greater the extent of silylation of anhydrosugars. For example, in an alum-treated fragment from Oseberg the relative abundance of anhydrosugars containing three silyl groups lies between 70 and 90%, while in sound alder tri-silylated anhydrosugars are found in the order of 40% [18].
Chemical variability can be found within single objects, as exemplified in the so-called 185-series, which is comprised of six fitted fragments from a loom, where there is progressively greater lignin oxidation and lower holocellulose content from one side of the object to the other [21, 26]. This parallels visual condition where the better preserved fragments having better structural integrity are lighter in colour than the less preserved fragments, which were extremely powdery and significantly darker.
Chemical variability was also investigated within individual fragments. Generally, the wood in fragments with alum-rich surfaces without linseed oil coatings was slightly more degraded than that in the alum-poor core, reflected in higher levels of oxidized lignin-derived pyrolysis products [21]. This may either be directly related to the alum-treatment or to the fact that surfaces are generally more degraded than cores in archaeological wood [1]. A slight preservative effect of linseed oil on wood has been observed in one alum-treated fragment containing linseed oil. Here holocellulose levels at the surface were slightly higher and lignin oxidation products were lower than those found in the core of the same fragment, where wood was not coated with oil [18].
Iron and inorganic compounds
In unrestored objects, the presence of iron originates from the burial environment. The iron content in Oseberg alum-treated wood samples analyzed by ICP-OES was 3.5 mmol/100 g or less [21, 26], much lower than that found in other published finds where iron content ranged from ca. 10 to several 100 mmol per 100 g of sample (mmol/100 g) [33,34,35].
In restored objects where extensive iron hardware was used, the acidic environment in the alum-treated wood has caused the corrosion of iron rods used in restoration. Some of these rods were accessible for sampling due to new breaks, and in these cases iron-containing minerals were located on the rods themselves and in the wood adjacent to them. These include various forms of both iron sulfates and iron potassium sulfates, demonstrating that iron ions have reacted with alum salts, or their derived products: szomolnokite (FeSO4·H2O), rozenite (FeSO4·4H2O), krausite (KFe(\({\text{SO}}_{4}^{}\))2·H2O), goldichite (KFe(\({\text{SO}}_{4}^{}\))2·4H2O), and voltaite (K2Fe II5 Fe III3 Al(SO4)12·18H2O) [36].
The corrosion layer on a nail from the Oseberg find which had not been exposed to the alum treatment was found to contain iron carbonate (FeCO3), gypsum (CaSO4·2H2O) and iron oxyhydroxides (lepidocrocite and goethite (FeO(OH)) by XRD [36]. The corrosion layers formed during burial are thus very different from those found on the newer iron rods used to reconstruct the object.
Higher levels of zinc, up to 4 mmol/100 g, were present in alum-treated wood than that found in either fresh wood or in Oseberg woods not treated with alum [26, 27]. Zinc originates from the water tanks used to store the fragments before treatment with alum salts. In one object, localized salt outbreaks in two regions away from restoration metals contained a mixture of gunningite (ZnSO4·H2O) and a mineral with composition K2[Zn(H2O)6](SO4)2, and ZnS (sphalerite). Sphalerite contains reduced sulfur and as such was an unusual find, as most sulfur present in the wood is in its oxidized form as sulfate from the alum salt. Reduced sulfur likely originates from the burial environment itself which was near the coast [8], presumably formed through the conversion of sulfates from sea water to sulfides by sulfate reducing bacteria [36].
Other compounds identified include mercallite (KHSO4) and alunite (KAl3(SO4)2(OH)6). Mercallite, which is acidic, has been found in samples which do not contain linseed oil and which are highly degraded, and as such may be another symptom of degradation [21]. Alunite has so far only been identified on surface samples, implying that it formed during treatment and not in post-treatment reactions in the alum salt [36].
A greenish material was found on the surface of a brass screw used to assemble fragments. By means of infrared analyses, the substance was found to be copper oleate, formed by a reaction between the linseed oil and copper from the screw.Footnote 13
Effect of RH on alum-treated wood
Sorption experiments of pure potassium alum showed that in the range of 30–75% RH and at 20 °C, very little moisture was adsorbed [27]. However, mercallite, present in small amounts in the wood is hygroscopic and will migrate under humid conditions.Footnote 14 New needle-like crystals (a form of potassium hydrogen sulfate) formed on the surfaces of fragments of alum-treated Oseberg wood without linseed oil which were maintained at 75% RH for ca. 2 years before being stored at lower RH levels.Footnote 15 Other experiments on alum-treated Oseberg wood without linseed oil have shown that the migration of these hygroscopic salts accompanies extensive damage of poorly preserved wooden fragments when exposed to extreme RH cycling at slightly elevated temperatures (30 °C) [33].
Regarding wood samples, sorption experiments using the same conditions as above demonstrated that untreated freeze dried archaeological wood and freeze dried Oseberg wood which had its alum removed by washing, showed higher moisture uptake, especially above 70% RH, than almost all other samples in the study which included: sound wood, archaeological wood recently treated with alum, Oseberg woods retreated by PEG 3000 and Oseberg samples with alum and alum/linseed oil [27]. The exception was for samples containing glycerol,Footnote 16 which had the greatest moisture uptake of all samples due to glycerol's high hygroscopicity.
Linking material knowledge to conservation issues
In the previous section, a summary of alum-treated wood's material properties was presented. How this material knowledge relates to decisions or actions involving the collection's preservation is discussed here.
Mechanical fragility
Chemical analyses of alum-treated woods show an extreme form of degradation not normally observed in archaeological wood. Such deterioration cannot only be attributed to natural aging, but is rather heavily influenced by the alum treatment itself. Acid formed in the hot alum solutions has been absorbed by the wood at the time of treatment, and has since caused the slow degradation of wood polymers. The acidic environment has also caused the corrosion of metal rods and pins used to restore the objects and may have accelerated other reactions, such as those between the brass screws and linseed oil. The current rate of degradation reactions is, however, unknown.
The reduced mechanical strength of alum-treated woods is therefore the result of a combination of bacterial degradation during burial, chemical degradation caused by the alum treatment and the mechanical damage originating during treatment and from aging of restoration materials.
Alum salts are unevenly distributed, and in objects greater than 1 cm in thickness and 10 cm in length one can expect to find alum-rich and alum-poor zones, implying the likely presence of internal cracks and voids. Areas of collapse can extend to the surface. Thus even single fragments may require very careful handling to avoid further damage. Corrosion of the iron rods used to hold fragments together may produce salts which expand in volume significantly, which in turn may lead to cracking of the adjacent wood or failed repairs.
Alum salts also add significant weight to fragments and in the most degraded samples, wood is more or less held together by alum salts. However, the salts generally do not contribute significantly to the global strength of the fragment. Therefore packing design and display mounts must offer full physical support. In larger fragments, losses of alum-rich surfaces may trigger extensive material loss from the weaker alum-poor regions.
Linseed oil has penetrated to the same extent as the alum salts, thus it too is concentrated on surfaces. Unlike alum, it generally provides good surface consolidation, which contributes to the preservation of carved surfaces. As it also offers a slight chemically-related preservative effect on the wood polymers, it does not seem necessary to remove it as long as it does not interfere with retreatment.
Improving mechanical properties of the object would be one of the aims in retreatment. Another aim would be to chemically stabilize this wood. Regarding eventual retreatment, aqueous-based methods involve several steps, starting with the immersion of a fragment in water to remove alum salts. The wood is simultaneously deacidified, as most acidic products are also removed during this step. After alum removal and deacidification, the fragment is immersed in a solution containing the strengthening polymer. We are testing two established aqueous methods, using polyethylene glycol (PEG) coupled with freeze drying and Kauramin followed by air drying. The type of PEG used (for example PEG 2000) is solid at room temperature. When dissolved in water, PEG molecules diffuse into the wood and form hydrogen bonds with the wood fabric. Freeze drying allows for lower concentrations to be used (40%, w/v) than that required for air drying, while still offering physical support to the wood cells. In the Kauramin treatment, a 25% (v/v) solution of Kauramin 800®, a propriety mixture of melamine and formaldehyde in monomeric and oligomeric forms, diffuses into the wood. The melamine and formaldehyde undergo in situ polymerization when solution conditions approach pH 6–7, resulting in an open melamine–formaldehyde resin network that supports the weakened wood cells [38]. Linseed oil does not appreciably hinder alum removal or impregnation of strengthening polymers. Immersion of the worst preserved fragments has not been successful, as they more or less disintegrate in water. Objects which have been restored will not withstand immersion either. For such objects, solvent-based strengthening agents are being investigated in Saving Oseberg [39,40,41,42,43].
Interaction with moisture
At the start of our work with the Oseberg collection, it was believed that the powdery nature of the wood was the result of the mechanical destruction of cells due to the dimensional changes of alum salts in response to moisture fluctuations. We have found that potassium alum salts do not take up water in the range 30–75% RH at 20 °C, in agreement with the Swedish National Heritage Board's results [4]. Our own experiments show that ammonium alum behaves in a similar manner.Footnote 17 On the other hand, hygroscopic salts present in minor amounts in the wood can migrate in the presence of moisture, possibly even at RH levels below their deliquescence point, as was observed in the formation of needle-like crystals under dryer conditions after storage at 75% RH. We hypothesize that these crystals result from reactions of mercallite, even though it deliquesces at 86% RH [37].
Wood samples fully impregnated with alum alone, with a combination of alum and linseed oil or retreated with PEG 3000, are not as sensitive to relative humidity as untreated freeze dried archaeological wood. As long as the impregnating agent is less hygroscopic than wood, it will reduce moisture uptake if it appreciably coats the wood structure. This can be explained by considering that the extremely deteriorated wood is highly porous and that the high degree of lignin oxidation increases the material's chemical polarity. Both factors lead to an increase in the number of interactive sites for water in untreated, degraded wood, resulting in higher equilibrium moisture contents than treated woods [44].
It can therefore be expected that wood in the more-or-less untreated alum-poor regions is more reactive to moisture than the alum-rich surfaces, especially above 70% RH. Wood from alum-poor zones exposed to the ambient environment through fractures in reconstructed objects can be pulverized by repeated swelling and shrinkage under fluctuating RH conditions, as shown by Mortensen et al. [33]. To prevent this, the RH should be kept relatively constant, and maintained in the range of 40–55% RH. Retreated objects should be stored at RH levels and fluctuation ranges appropriate for the polymer-wood combination used in retreatment, evaluated through sorption measurements.
Chemical reactivity of inorganic compounds in the wood
Alum salt is the major inorganic compound in the wood. Contrary to previous views, which promoted the idea that alum salts are hygroscopic, we have established that they are not moisture sensitive and thus do not pose a risk for mechanical damage due to RH fluctuations. Whether alum salts partake in ongoing chemical deterioration reactions, directly or indirectly, is under investigation, as discussed below.
The pH values of alum-treated woods do not distinguish levels of deterioration very well. This either indicates that acid hydrolysis is not the only reaction involved in degradation or that hydrolytic reactions may also involve aluminum ions, which are electron acceptors just like protons, but are not measurable by pH, which only accounts for proton activity. In acidic solutions at elevated temperatures aluminum ions catalyze isomerization reactions in sugars, such as those which convert glucose into fructose; they also promote dehydration reactions of sugars [45].
Analyses indicate that that the aluminum content is mainly affiliated with alum salts. Whether aluminum ions are capable of undergoing the reactions mentioned above when in the solid state is uncertain. We are looking into the possibility that small amounts of potassium may be leached from potassium alum in the presence of more hygroscopic minerals such as mercallite. This in turn may lead to a destabilization of the alum salt itself, making aluminum more reactive in such cases. The influence of ammonium alum on such reactions is also under investigation. Thus some of the other minerals identified may have arisen through reactions either with alum directly, with the alum salt's breakdown products, or both.
Other inorganic compounds
The iron-containing minerals identified in the wood can be sources of ferrous ions, which in turn can lead to oxidative degradation of wood [46, 47]. It should be noted, however, that such compounds were generally only found in proximity to the iron rods used in restoration, indicating that iron ions have not migrated very far, and that potential iron-induced reactions are local. We attempted to correlate iron content as determined by ICP-OES with amounts of acidic lignin pyrolysis products, but found only weak correlations. This suggests that iron-induced degradation is likely minor.
There is no evidence in the literature indicating that zinc is involved in wood degradation reactions, but the powder containing both gunningite and K2[Zn(H2O)6](SO4)2 is acidic, pH 2.5, and can thus indirectly cause local damage.
The thermodynamic stabilities of the chemical systems containing alum and the other major salts identified are still being researched, as we are interested in knowing whether they pose a preservation threat.
Dealing with acidity and inorganic compounds
Wood's absorption of excess acidic sulfates produced during the alum treatment has been confirmed by chemical analyses. Besides alum, sulfates are associated with iron, potassium and zinc in several mineral forms. For the salt efflorescence on the surface of an object, in which zinc, iron and alum salts have been identified as well as elemental sulfur, pH of 2.5 was measured. Such salts likely also contribute to the low pH values observed in some woods (pH 1). However, in the wood samples analysed for sulfate content, the level of sulfates significantly exceeded the levels of metal cations, so the identities of the counter-ions for all acidic sulfate species remains uncertain.
Lack of firm correlations of iron with wood degradation have made us question the necessity to remove it during an eventual reconservation. Such a step may introduce unnecessary risks. Deacidification may be the best option to reduce possible ongoing hydrolytic reactions and local reactions potentially involving iron, since high acidity favours both iron corrosion—observed in the iron hardware used to restore the objects—and iron-catalyzed oxidative processes in wood.
Deacidification may be approached in two ways: either by immersion in water, a step in retreatment methods using aqueous-based polymers such as PEG [4] and Kauramin or by adding a deacidifying agent such as alkaline nanoparticles (NP) suspended in isopropanol [42]. We are investigating both avenues in ongoing experiments on original material. Deacidification by NPs does not extract alum, as alum is insoluble in isopropanol. However, NPs may react with it or with its derived products and form new minerals. Such reactions are being examined as they must be understood before we can recommend this type of deacidification treatment.
Insight into variability in visual and chemical states of preservation
Chemical variation has been found within single objects where there are alum-rich and alum-poor zones, linseed oil and iron parts. This type of variation is more or less consistently observed in alum-treated wood. However there are also examples of variability in condition within single objects, such as in the so-called 185-series, which are not yet fully understood, despite extensive investigation. Likewise, we do not fully understand the reasons behind the diverse range of visual states of preservation among different objects in the collection. For these objects, we can roughly relate the chemical state of preservation to an object's/fragment's colour and consistency [22]. Generally, the darker the wood, the more powdery it is and the greater is the degradation (extent of oxidation) of the lignin polymers (see Fig. 10). As mentioned earlier, iron content and pH values show only a modest correlation with visual condition.
Variability in the current state of preservation of the objects may be partly related to the original condition upon recovery. Brøgger et al. [6] noted that there was a range of preservation states, as fragments in very poor condition were treated in alum solutions which had higher concentrations than that used on finds which were less degraded. They also noted that the alum-treatment gave best results on wood that was evenly degraded to the core. Today we observe that the few examples of ring-porous woods (such as oak) conserved with alum are in a better state of preservation than alum-treated woods of the diffuse-porous type (such as birch or maple), which may indicate better initial condition, or it may be due to the fact that these fragments are small and saturated with linseed oil. Linseed oil appears to protect the wood to some extent from degradation. In other cases, especially in objects where linseed oil has not penetrated the fragment completely or those without linseed oil, as in the object named 185-series, we see that fragments from a single object display differences in state of preservation which are extreme.
Brøgger et al. [6] also stated that larger fragments were treated for longer periods than smaller fragments. Immersion time in the acidic treatment solutions may be a factor which affects current condition, but it does not explain the differences observed in the 185-series, fragments from which were presumably conserved at the same time. Another possible factor contributing to observed variability in state of preservation may be related to when the object was treated. During the 7-year period of alum-treatment, it is unknown whether fresh alum baths were made regularly, or if baths were merely topped up with alum and/or water as needed. If the latter, older solutions may have had greater acidity due to the steady precipitation of alunite; woods conserved later will have absorbed more acid than woods conserved earlier. Finally, we have found both potassium alum and mixtures of ammonium and potassium alums in the analyzed woods. Current experiments showed that hot (90 °C) ammonium alum solutions do not decrease in pH as do potassium alum solutions. This may imply that not as much acid has been absorbed by fragments treated in alum mixtures, and therefore they may exhibit less degradation today. Inorganic compounds other than alum are generally present in the wood in much smaller quantities than alum salts, but may nonetheless contribute to degradation through reactions that are not yet understood.
Thus, the type(s) of alum used, their breakdown products, the solution concentration, immersion time, whether linseed oil was used and the time at which treatment took place are variables that may affect current condition. These factors may weigh more heavily than differences in initial burial condition. Unfortunately, little information about such details exists in archival material. Ongoing experiments on the behavior of heated alum solutions over time, and the response of alum salts in the solid state to different temperatures and RH, however, will provide greater insight. Further efforts to relate degree of wood degradation to inorganic content are also underway.
Conclusions and further work
The conservation research in Saving Oseberg is driven by topics that will contribute to the development of sound, balanced decisions for preserving the Oseberg collection. Preservation strategies will likely involve invasive reconservation to reduce acidity and strengthen the object and/or implementation of preventive measures to slow down deterioration. Dealing with wood in different states of preservation and objects reconstructed to different degrees will require different preservation approaches.
Fundamental research on the alum treatment within the scope of wood conservation is scarce and as such, relevant information from other research fields, such as chemistry, wood science, soil science, mineralogy and geology had to be extracted and related to our investigations, a process which is time-consuming and not always easily adaptable. In effect, we are simultaneously undertaking both fundamental and applied research. Despite these challenges, our interdisciplinary teamwork has yielded new knowledge about this complex material, summarized in this paper. Chemical analysis of alum-treated wood is challenging and requires complementary techniques. We have mentioned analytical techniques which have provided information about the chemical state of preservation of the wood and identified which salts besides alum are present. The significance of analytical results is fed back into the overall conservation context. Our emerging understanding, as well as our analytical approach, is transferable to other alum-treated collections without glycerol and as such we hope that it will be a useful resource.
Answers to research questions still must be shaped by further work. Further investigations of the chemical reactivity of the inorganic compounds identified in the wood may provide more insight into variability in condition. Hopefully, such insight will also provide a better understanding of the current rate of decay in the objects. It is also important to investigate the chemical reactivities of inorganic compounds at the target pH levels aimed for in deacidification (pH 5–6) as they may differ from those at the current acidic levels.
Continuing material-related research runs parallel to that exploring the effects and limitations of different invasive reconservation methods for the simpler objects. Tests on small fragments using two established aqueous-based methods are currently underway: PEG coupled with freeze drying and Kauramin followed by air-drying. These methods are not applicable to highly degraded or extensively restored objects as they require immersion. Research on alternative invasive non-aqueous methods is also underway. Results will provide us with better knowledge about the effect of invasive reconservation strategies for objects in different states of preservation and identify the types and extent of damage that could result from retreatment. This knowledge will be used to assess whether invasive retreatments should be applied and if so, which methods are best to use in different cases. Estimates of remaining lifetime of the alum-treated objects will provide a context within which risk may be evaluated, and allow for informed decisions to ensure their future preservation.
The Viking Ship Museum is administered by the Museum of Cultural History, University of Oslo (KHM).
Indeed, the alum treatment applied to archaeological woods in our own experiments [12] clearly gave good results, making it understandable that the treatment was considered to be successful even as late as the early 1970s [8].
[6], p. 102.
[6] p. 103.
The recipe used for this putty is given in Johannessen's journal [13]. 'Dextrine putty: five parts plaster, one part dextrine, pigment'. Dextrine is a starch derivative, made by heating starch (from potatoes, corn) with acid. Also known as British gum [14].
Kutzke, unpublished analyses. The occurrence of calcium sulfate hemihydrate in some samples leads to the assumption that the mentioned plaster is Plaster of Paris, a calcined form of gypsum which was widely used as restoration material. The hemihydrate can attract water over time and transform to gypsum, a process which may be hindered in some cases by the protection of coatings.
'Matte varnish', applied to the objects after reconstruction has not been further specified in the accounts given of the conservation process.
Kutzke, unpublished analyses.
Braovac, unpublished experimental results.
Although the method of wood identification was not reported in the excavation publications, the light microscope almost certainly was not used, as beech (Fagus sp.)—assigned to the majority of objects treated with alum—has so far not been found, but is easily distinguished from birch under high magnification, even in contemporary literature [25].
Mercallite has a deliquesence point at 86% RH and 15 °C [37].
McQueen and Braovac, unpublished experimental work.
Kindly donated by the National Museum of Denmark.
Braovac, unpublished experimental work.
Christensen BB. The conservation of waterlogged wood in the National Museum of Denmark: with a report on the methods chosen for the stabilization of the timbers of the viking ships from Roskilde Fjord, and a report on experiments carried out in order to improve upon these methods. Copenhagen: The National Museum of Denmark; 1970. p. 118
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Łucejko JJ, Tamburini D, Braovac S, McQueen C, Gambineri F. Saving Oseberg January 2013–September 2016 Technical Report Part 1: Analyses and characterization of alum-treated wood without other additives. Oslo: Museum of Cultural History, University of Oslo; 2017.
Hoffmann P, Schwab E, Bonde N. Report on strength tests performed on wood samples from the Gokstad Ship and boats, and from the Oseberg finds complex, and some observations on strakes from the Gokstad, Oseberg and Tune ships. In: Bøe A, editor. Vikingskipsseminaret. Oslo: University of Oslo; 2002. p. 60–74.
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All authors have participated in extensive discussions regarding the conservation implications of the research results. SB was responsible for the main writing of the manuscript, interpretation of wood analyses, microscopy and tomography data acquisition; CM acquired and interpreted data about inorganic compounds and restoration materials; JL acquired and interpreted data about wood polymer analyses; HK acquired and interpreted data on restoration materials and tomography data acquisition; and; TK acquired X-radiography data. All authors read and approved the final manuscript.
Authors' information
Susan Braovac, Ph.D., archaeological conservator at the Museum of Cultural History who has been working on various aspects of the Oseberg collection since the mid-1990s: risk analyses, chemical analyses, reconservation strategies.
Caitlin M.A. McQueen, Ph.D., chemist at the Museum of Cultural History, who has been doing research in the Saving Oseberg project since 2014 on chemical analysis of alum-treated wood with a focus on inorganic components.
Malin Sahlstedt, M.Sc., conservator at The Swedish National Maritime Museums with experience from archaeological wood preservation projects at The Swedish National Heritage Board (2002–2009), The Vasa Museum (2009–present) and University of Oslo in Saving Oseberg (2017–2018).
Hartmut Kutzke, Ph.D., chemist and conservation scientist at the Museum of Cultural History, Oslo. Main research interests: analyses of cultural heritage objects, written sources on art technology, and development of bio-inspired conservation materials.
Jeannette J. Lucejko Ph.D., researcher at the University of Pisa. Research activity concerns the study of modifications undergone by polymers in archaeological waterlogged wooden artefacts by means of mass spectrometric methods.
Torunn Klokkernes, Ph.D., senior conservator and former head of department at the Museum of Cultural History. Research interests are the technology and material science of archaeological and historic artefact materials.
This work was carried out as part of the Saving Oseberg project, funded by the Norwegian Ministry of Education and Research and University of Oslo. X-ray tomographic microscopic imaging was undertaken under the guidance of beamline scientist Dr. Rajmund Mokso at TOMCAT, Paul Scherrer Institute (PSI), Villingen, Switzerland. Rendering of imaging data was accomplished at SINQ, PSI with assistance from Dr. David Mannes. The authors would like to thank Dr. Louis Boumans and the reviewers for their constructive feedback on the manuscript.
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
Malin Sahlstedt
Present address: Collections Unit Vasa Museum, P.O.Box 27131, 102 52, Stockholm, Sweden
Department of Collection Management, Museum of Cultural History, University of Oslo, Postbox 6762, St. Olavs plass, 0130, Oslo, Norway
Susan Braovac, Caitlin M. A. McQueen, Malin Sahlstedt, Hartmut Kutzke & Torunn Klokkernes
Department of Chemistry and Industrial Chemistry, University of Pisa, 56124, Pisa, PI, Italy
Jeannette J. Łucejko
Susan Braovac
Caitlin M. A. McQueen
Hartmut Kutzke
Torunn Klokkernes
Correspondence to Susan Braovac.
Braovac, S., McQueen, C.M.A., Sahlstedt, M. et al. Navigating conservation strategies: linking material research on alum-treated wood from the Oseberg collection to conservation decisions. Herit Sci 6, 77 (2018). https://doi.org/10.1186/s40494-018-0241-y
Oseberg find
Wood degradation
Alum-treated wood
Potassium aluminum sulfate
Ammonium aluminum sulfate
Chemical analyses
Retreatment
Saving Oseberg


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The Romans in Britain
Poster designed by Richard Bird advertising the original 1980 National Theatre production.
Howard Brenton
Date premiered
Place premiered
The National Theatre, London
North of the River Thames (55 BC)
Britain (515 AD)
Ireland (1980 AD)
The Romans in Britain is a 1980 stage play by Howard Brenton that comments upon imperialism and the abuse of power. It was the subject of a private prosecution for gross indecency.
A cast of thirty actors play sixty roles.
1 Stage history
Stage history
The play was first staged at the National Theatre in London on 16 October 1980. In 1982 it became the focus of an unsuccessful private prosecution by Christian morality campaigner Mary Whitehouse against the play's director Michael Bogdanov relating to the on-stage depiction of homosexual rape.[1] This prosecution was defeated when Whitehouse's solicitor, Graham Ross-Cornes, the chief witness against Bogdanov, revealed under cross-examination that he had been sitting at the very back of the theatre when he saw what was claimed to be a penis. The prosecution withdrew after lead defence counsel Jeremy Hutchinson QC demonstrated that Ross-Cornes could have witnessed the actor's thumb protruding from his fist. The case was ended after the Attorney-General entered a nolle prosequi.[2]
Actor-director Samuel West revived the play in 2006 at the Crucible Theatre, Sheffield, starring Tom Mannion as Julius Caesar and Dan Stevens as Marban the Druid.
^ Mark Lawson, She claimed that there was a wider threat to society and that men might be "so stimulated" by watching the scene in the Olivier that they would "commit attacks on young boys"."Passion play", The Guardian, 28 October 2005
^ Robertson, Geoffrey (1999). The Justice Game. London: Vintage. ISBN 978-0-09-958191-8.
Howard Brenton, The Romans in Britain (London: Eyre Methuen, 1980) ISBN 0-413-46590-X
Mediawatch formally the National Viewers and Listeners Association (campaign group), opinion article.
Look Back in Anger The Guardian, January 2006, feature article.
Review round-up about the 2006 Sheffield production
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Rush Alpha Phi Omega at the beginning of each semester to join our brotherhood!
Brothers participate in service projects in the Atlanta area, such as volunteering to help with trail maintenance at Kittredge Park. Many of our brothers earn the Presidential Service Award, earning more than 100 hours in a year!
Through their service to others, Alpha Phi Omega brothers serve as leaders in their community.
Friendship is the key feature of Alpha Phi Omega that transforms it from an organization into a brotherhood.
Brothers are initially drawn to Alpha Phi Omega for its dedication to service.


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Processing the Hugh Morton Photographs and Films
Covering the Beat: The University in the WWII Era
Hugh MacRae at Invershiel
Hugh Morton Among the Movers and Shakers
Hugh Morton and North Carolina's Native Plants
The Grandfather Backcountry: A Bridge Between the Past and Preservation
The Tar Heels' 'White House Photographer'
Wilmington: Faded Glory to Fresh Achievement
A priceless gem for only ten bucks
Posted on October 27, 2018 by Stephen Fletcher
UNC President C.D. Spangler standing outside the President's house on UNC-Chapel Hill campus, February 23, 1988, holding a ripped #22 jersey worn by UNC football player Charlie Justice during the 1948 game against Virginia.
Today, October 27th, UNC head football coach Larry Fedora leads his 2018 Tar Heels into historic Scott Stadium for a continuation of "the South's Oldest Rivalry." This game between the University of North Carolina and the University of Virginia marks the 123rd meeting between the two old rivals. Over the years, since the first meeting between the two in 1892, Carolina has won sixty-four times while UVA has won fifty-four; four games ended in a tie. Of the fifty times Carolina has played UVA on the road, the game in 1948 not only provided Carolina with a highly significant win, it also provided an interesting sidebar story. Morton collection volunteer Jack Hilliard takes a look back at the game in Scott Stadium on November 27, 1948 between the Tar Heels and the Cavaliers.
Arguably the best UNC football team was the 1948 squad that finished the season undefeated and ranked third in the Associated Press poll. The '48 Tar Heels started off the season at home with a historic win over the University of Texas, 34 to 7. (Many old-time Tar Heels still like to talk about this game.)
The weekend following the Texas win, Charlie Justice had his best day as a Tar Heel down in Georgia with a win over the Bulldogs. Then came wins over Wake Forest, NC State, LSU, and Tennessee. A tie with William & Mary on November 6th was the only blemish on the '48 schedule. Following wins over Maryland and Duke, it was time to close out the historic season—a season that had seen Carolina ranked number one for the first and only time.
With bowl talk in the air, Head Coach Carl Snavely took his team into Scott Stadium for that finale. An overflow crowd of 26,000+ turned out on November 27, 1948, a day that could have very easily been called "Charlie Justice Day." Here's why:
He got off runs of twenty-two and eight yards in the initial Carolina touchdown drive.
He passed thirty-nine yards to receiver Art Weiner for the second Tar Heel score.
He cut off left guard on a delayed spinner and outran the field to cross the Virginia goal eighty yards away.
He passed thirty-one yards to end Bob Cox for Carolina's fourth touchdown.
He returned a UVA punt, in a straight line, fifty yards for Carolina's final touchdown of the day.
In summary: Justice carried the ball fifteen times for a net total of 159 yards—that's almost 11 yards per carry. He completed four of seven passes for 87 yards. He returned two punts for sixty-six yards. He punted five times for a 40.8 yards per punt average. And oh yes, he intercepted a Virginia pass, had a 49-yard touchdown pass called back as well as a 21-yard run. Needless to say, Carolina won the game 34 to 12 and went on to play in the 1949 Sugar Bowl.
Among those 26,000+ fans in Scott Stadium that afternoon was an eleventh grade student at Woodberry Forest, a prep school in Madison, Virginia. His name, Clemmie Dixon Spangler, Jr. from Charlotte, North Carolina. Spangler, along with several of his school buddies, had made the trip over to Charlottesville for the game. (Clemmie Dixon Spangler, Jr. would become known as C.D. Spangler, Jr. and would lead the University of North Carolina system from 1986 until 1997.)
On one of those great Charlie Justice plays mentioned above, Justice's #22 jersey was torn. He came over to the Carolina sideline where equipment manager, "Sarge" Keller, quickly got out a new one . . . tossing the torn one over behind the bench into an equipment trunk. In a 1996 interview with A.J Carr of Raleigh's News & Observer, Spangler described the 1948 Charlottesville scene:
"Charlie was a hero of mine. It was one of his greatest college games. On one play, a linebacker grabbed him, but he twisted away as he often did, ran another 10-15 yards and his jersey was torn."
"He came over, the trainer helped him put on another and they put the torn one in the trunk. I said: 'That old jersey would be nice to have.'"
After the game, Spangler got the attention of a Carolina cheerleader and explained that he wanted the Justice jersey. He then offered the cheerleader ten dollars to go and get the jersey out of the trunk. The deal was completed and as Spangler walked out of the stadium, some Carolina fans offered him one hundred dollars. Spangler said, "No deal."
He displayed the jersey on the wall while in high school and after graduation he kept it in a "safe place."
"I wouldn't take anything for it," Spangler continued. "It's a piece of history that meant something to me."
"My mother offered to wash it and sew it. But I said we would not wash it, that we'd keep the lime marks and grass stains and leave it torn."
"(Charlie Justice) is very symbolic of someone who did well, was a hero and he lived a really good life. He lived up to all expectations and has been a fine representative for North Carolina," Spangler added as he closed the interview.
Photographs of Charlie Justice and C.D. Spangler stored in Machine Print Envelope 2.6.398-10-9. One of the prints has a caption typed on the back with the ubiquitous stamp, "PHOTOGRAPH BY HUGH MORTON."
Spangler kept the prized memento for more than fifty years. Then, on November 18, 1989, during halftime of the Carolina–Duke game, he presented the jersey to then UNC Athletic Director Dick Baddour. It is now on display in the Charlie Justice Hall of Honor at the Kenan Football Center.
A mounted color photograph autographed by Justice and Spangler, located in Oversize Box 2 in the Hugh Morton collection
Morton also used the images in his slides shows, saying: "…the only university president who freely admits to bribery and stealing."
Photographs and negatives from Machine Print Envelope 2.6.398-10-6. The envelope contains negatives from two rolls of film, one of which is seen here on the left. The negative for the print with Justice and Spangler standing next to the torn jersey exhibit case is not in the envelope. It would fit sequentially in the space seen next to the upper right corner of the print. Above that print, on Spangler's right is Julia Morton; to his left is Betty Kenan.
On April 30, 1984, the Charlotte chapter of the Juvenile Diabetes Foundation staged a Charlie Justice Celebrity Roast and one of the roasters was Justice's dear friend, teammate, and business partner Art Weiner. One of Weiner's roast stories went something like this:
We knew that Charlie was competing with SMU's great All America Doak Walker for the 1948 Heisman Memorial Trophy. When we read in the papers that Walker had a jersey torn up during one his games, we decided, in the huddle, to tear up one of Charlie's . . . just to make things look equal. But on November 27, 1948, the tear was for real and C.D. Spangler, Jr. got a "Priceless Gem for Only 10 Bucks."
This entry was posted in Behind the Scenes, Football, Sports, UNC by Stephen Fletcher. Bookmark the permalink.
4 thoughts on "A priceless gem for only ten bucks"
Lew Powell on December 2, 2018 at 11:53 am said:
A different kind of Justice memorabilia (not game-worn)…..https://www.etsy.com/listing/659035365/1950s-retro-football-helmet-charlie-choo?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=choo+choo+charlie&ref=sr_gallery-1-5
Jack Hilliard on December 2, 2018 at 8:36 pm said:
You are right on point. Lew, when you say "not-game-worn." This helmet falls in the same category as that Justice uniform we discussed in a "comment-conversation" back on January 16, 2012.
This helmet appears to be part of an arrangement Justice made with Wilson Sporting Goods soon after his 1950 College All-Star MVP performance in Chicago on August 11, 1950. Justice agreed to let Wilson use his name and facsimile autograph. Wilson in turn marketed to Montgomery Ward and most likely others. The helmet was listed in the 1954 Montgomery Ward Christmas catalog as well as their 1955-56 Fall and Winter general catalog.
So, in reality, Justice didn't have any direct, hands-on connection with the helmet. It just carried his famous name.
Always appreciate your comments, Lew.
Lew Powell on December 3, 2018 at 6:57 am said:
Thanks as always, Jack…. This was pretty early in what has become the sports endorsement mega-industry…. Wonder what compensation Wilson offered….
Interesting question, Lew. I don't know what Charlie's compensation was for the Wilson deal back in 1950. I do know that the endorsement arrangement, in addition to Justice, included deals with Bobby Layne of Texas, and Harry Gilmer of Alabama. (Justice and Gilmer were teammates with the Redskins in the early '50s.)
The 1955 catalog price for the Justice helmet was $3.95…about the same price as a Redskins – Packers preseason ticket in Winston-Salem's Bowman Gray Stadium.


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Buckeye Police release body camera footage of June 2016 officer involved shooting
BUCKEYE, Ariz. (KSAZ) - NOTE: The video contains graphic content. Viewer discretion is advised.
On Thursday, Buckeye Police released body camera footage of an officer involved shooting that took place nearly one year ago.
The officer involved shooting happened on June 25, 2016, at the 20000 block of West Wayland Drive, and the suspect was identified as William Ferguson, 30. According to the statement, the officers responded to a report from family members that Ferguson had shot his wife, identified as 36-year-old Breanne Ferguson.
When the officers arrived, Buckeye Police officials said Ferguson, who was heavily armed, started firing rounds at the officers, and the officers were forced to respond with gunfire. The shootout lasted almost a minute before officers could try and make their way closer to find where William Ferguson was.
Buckeye Police officials said the video's release was delayed, at the request of the Maricopa County Attorney's Office, who requested them to wait until the case is resolved. On May 30, the County Attorney's Office sent a letter addressed to Buckeye Police Chief Larry Hall, which states the Office's Shooting Review Board believe the officers involved did not commit any act that warrants criminal prosecution.
Mug Shot Gallery - January 2021


Sushi is usually not very accessible in Bucharest. But Ai is an exception. And a very tasty and generous one.
Ai is also the kind of small restaurant that leaves you with the impression that it was made by friends for friends. Not just any kind of friends, but those who, first of all, love good food, mainly of Asian inspiration. And all day breakfast. Very good breakfast.
Equally, it's one of the few places in the city that serves Eggs Benedict (with salmon or prosciutto). You can also get Teriyaki, noodles, miso, tartar and salads. Overall, the menu is very intriguing.
I really recommend their website, since it is visually playful and gives you a better sense of what Ai has to offer.
Last but not least, Ai is within walking distance from Piața Victoriei, located in one of the nicest and fanciest neighborhoods in the city, Dorobanți, not far from Herăstrău Park.
So many reasons to visit, right?


BOSTON — Ocean seagrass meadows reduce bacteria unhealthful to humans and marine organisms by up to 50%, a new study shows, and they also decrease the likelihood of disease in coral reefs by half.
Not only could seagrasses help improve water quality and maintain the health of marine ecosystems in increasingly populated coastal zones, where an estimated 1 billion people are projected to reside by 2060, but these plants also play a key role in sustaining the rapid increase in the aquaculture industry occurring in recent years in the face of global food shortages.
The study, published in the 17 February issue of the journal Science, was the focus of a press briefing at the 2017 AAAS Annual Meeting in Boston.
Removing human pathogens from water is essential for human health. Plants, with their natural microbe-killing compounds, play a vital role – one that can offer significant economic benefits. For example, in recent years, New York City opted to purchase and restore wetland habitat in a nearby catchment area instead of building an $8 billion treatment plant, saving the city billions in capital and ongoing costs.
Although seagrasses are known to produce natural antibiotics, they have not been evaluated for their ability to remove pathogens from the ocean, or for their ability to mitigate disease among organisms living there.
Working in waters off four Indonesian islands, Harvell, Lamb and colleagues sought to assess the influence of seagrass on marine microbial pathogens and disease – an effort in part inspired by their team members first getting sick in this location while studying coral beds.
In shore waters off these islands, the researchers studied bacterial composition. The group used Enterococcus tests, the EPA standard to determine beach closures, to see whether seagrass meadows influenced bacterial levels. Seawater samples of Enterococcus exceeded EPA human health risk exposure levels by a factor of 10 for bacteria in recreational waters.
Levels of Enterococcus were reduced three-fold, however, in areas where seagrass was abundant, the researchers found.
Further studies by Harvell, Lamb and their team revealed that pathogens of fish and marine invertebrates were also much lower in number when seagrass was present – by 50%.
Because seagrass meadows and coral reefs are usually linked habitats, the team also examined more than 8,000 reef-building corals for disease. Disease levels were two-fold lower on reefs with adjacent seagrass beds than on reefs without nearby grasses, they report.
"This is the first study to assess whether a coastal ecosystem is capable of alleviating diseases that affect and associated marine organisms," said Lamb.
At this point, Lamb and colleagues do not fully understand the exact mechanisms that are driving the reductions in bacterial loads of seawater within seagrass ecosystems. An intact seagrass ecosystem comprises a diversity of bivalves like clams, sponges and tunicates like sea squirts that could further remove bacteria from the water column. Lamb and colleagues are now considering this further.
"Our findings are the beginning of a solution to dialing back the pollution that can cause disease in both ocean wildlife, and humans," said Harvell.


Carmeuse is a Belgian based world leader in the lime industry, founded in 1860, and is still a family owned business. The group is structured in 4 regions: the Americas, Europe, Middle East & Asia and Overseas, the latter one taking care of the rest of the world, with a special focus on Africa.
Managing content publication on CZ/HU/SK website, social medias, brochures, presentation, e-mailing campaigns.
Support in our events & fairs in Hungary-help with invitations/organizations/ commercial opportunities follow up, help to find local suppliers for brochures, events, videos, online referencing, gifts for customers, etc.


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Home All Mercato 26m Series Sea Venturespereztechcrunch
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Zayn Malik sale hotels and deals Zayn Malik tour tag 20-09-19 02:34 PM EDT – Lyrics of the song "I am… Free View in iTunes 49 Explicit Episode 170 – Riviera 2.0 What will become of India's new digital transformation? Will it work? Will it be a failure? It's a critical question, as India is on the cusp of an unprecedented digital transformation — one that will reshape its economy, its identity, and its future role in the world. And, just like every other country, India is falling behind. In this episode , we explore the challenges ahead and what we can do about it.
India's digital transformation: Can it happen?
While the digital transformation promises to be a key driver of growth in the Indian economy, it is only part of the picture. There is much room for improvement in terms of the digital content and experience we have, which are the foundations of strong digital transformation.
India risks falling behind in digital transformation
More than any other country in the world, India is behind in digital transformation. It has failed to adopt modern technologies such as Internet,eria, and Blockchain, which are all essential to driving transformation and transformation, transformation and transformation. It has also failed to adequately prepare for the requirements of 5G, AI, and the demands of a connected society. Organizations, including the Indian government, are wrestling with the question of how to make the best use of these new technologies.
Digital transformation: A must-know for India
The transformation of our digital ecosystem depends on the adoption of new technologies. One of the most promising technologies that can help India achieve digital transformation is Internet. The Indian Internet ecosystem currently consists of a large number of service providers including online banking, online mall buying, online shopping, online news, and online education. The challenge for India lies in the quality of these startups. India has a long way to go before it becomes a full-blown internet country.
Ripples in digital transformation — What will become of India's new digital transformation?
In order to drive digital transformation, it is essential to have a strategy that involves both static and digital transformation. The static part refers to the build-out of new technologies and their implementation, while the Digital transformation refers to the evolution of the ecosystem — the consumption, creation, and management of digital content.
What will digital transformation succeed or fail?
India is one of the few Asian countries that has not yet fully developed a digital transformation strategy. It is also one of the few countries that is still relatively young in the digital transformation process. Most of the digital transformation strategies in Asia and Western Europe are emerging companies' efforts. For example, in Asia, the efforts of Facebook, Instagram, and other social media platforms are still relatively new. In Europe, there are no established digital transformation strategies in place.
The big question mark is still hanging over India's digital transformation strategy. Is it worth the wait? As the biggest country in Asia, it is also one of the most important markets for digital transformation. The Indian economy is also a key market for India's digital transformation strategy as it will be the country that will drive the adoption of the most advanced digital technologies. If the digital transformation strategy fails, what will become of India's digital identity, economy, and future role in the world? How will the Indian government respond to this? In the end, this is a critical question — Will digital transformation succeed or fail? We hope that the answers are better than you might have thought.
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Auntie Mame (1958)
Village East Cinema (map)
See Hedda Lettuce perform live as she hosts the most eclectic event in the East Village at Village East Cinema.
Funny Girl (1968)
Sunset Boulevard (1950)
Dr. Jekyll and Mr. Hyde (1941)
Gentle Dr. Jekyll (Spencer Tracy) experiments with human nature, believing that each person has both good and evil sides that can be brought forth chemically.
The Two Mrs. Carrolls (1947)
Hiding his marital status from Sally, Geoffrey goes on to paint a foreboding portrait of his spouse and then kills her by gradually slipping her poison.
Rosemary's Baby (1968)
A young wife (Mia Farrow) comes to believe that her offspring is not of this world.
Berserk! (1967)
As the co-owner and ringmaster of a traveling circus, Monica Rivers (Joan Crawford) is always preoccupied with filling seats.
Trog (1970)
An anthropologist (Joan Crawford) works with her subject, an ice-age troglodyte found in an English cave.
Mildred Pierce (1945)
When Mildred Pierce's (Joan Crawford) wealthy husband leaves her for another woman, Mildred decides to raise her two daughters on her own.
The Women (1939)
Mary Haines (Norma Shearer) can't believe her husband's having an affair with salesgirl Crystal (Joan Crawford).
Rain (1932)
Passengers of a boat must disembark prematurely at the island of Pago Pago due to a cholera scare—among them are missionaries Alfred Davidson (Walter Huston) and his wife (Beulah Bondi), and a spirited prostitute, Sadie Thompson (Joan Crawford).
The Poseidon Adventure (1972)
the 1972 film surrounding a group of passengers who struggle to survive and escape when their ocean liner completely capsizes at sea.
As a new star and planet hurtle toward a doomed Earth, a small group of survivalists frantically work to complete the rocket which will take them to their new home.
Airport 1975 (1974)
1974 film in which a 747 in flight collides with a small plane, and is rendered pilotless. Somehow the control tower must get a pilot aboard so the jet can land.
Earthquake (1974)
The 1974 film that follows various interconnected people struggle to survive when an earthquake of unimaginable magnitude hits Los Angeles.
Hedda highlights the highs, lows, and absurdities of the 1951 film in which an alien lands and tells the people of Earth that they must live peacefully or be destroyed as a danger to other planets.
The Golden Globe nominated film centered around a Los Angeles male escort (Richard Gere), who mostly caters to an older female clientèle, is accused of a murder which he did not commit.
The crime thriller that follows a detective who goes undercover to find the serial killer targeting gay men, in particular those associated with the leather scene.
The Roman Spring of Mrs. Stone (1961)
the 60s romance film chronicling the adventures of a young woman in Italy after her husband's sudden death.
Looking for Mr. Goodbar (1977)
Hedda highlights the highs, lows and absurdities of the 70s Diane Keaton film about a school teacher's double life as she travels to various clubs to pick up men and drugs.
Serial Mom (1994)
New York City's Premiere Drag Queen Hedda Lettuce presents SERIAL MOM, an interactive event the likes of Rocky Horror meets Mystery Science Theater with barbed wit.
Annual 'Mommie Dearest' Interactive
Hedda Lettuce weaves her way in and out of the film, interacting with it, while pianist Rachel Kaufman underscores the drama, highlighting the insanity of Faye Dunaway's performance.
The Best of Everything (1959)
Three New York secretaries work their way through their small company.
Hush...Hush, Sweet Charlotte (1964)
Wealthy, aging spinster, Charlotte (Davis) receives a visit from her long-lost cousin, Miriam (de Havilland). With Charlotte's mental state deteriorating from hallucinations of her deceased former lover, Miriam sees this as the best opportunity to take control of her cousin's wealth.
Jezebel (1938)
With comedy, and commentary, Hedda highlights the highs, lows, and absurdities of the cinematic take on the 1930s hit chronicling the ups and downs of a spoiled yet headstrong Southern belle (Davis) and her attempts to win back her fiance (Fonda).
What Ever Happened to Baby Jane? (1962)
The two sisters have always one-upped each other in terms of fame as they grew up. However, after an accident leaves Blanche wheelchair bound, Jane is left to take care of her.
Heathers (1988)
Cinépolis Chelsea (map)
Veronica (Winona Ryder) is part of the most popular clique at her high school, but she disapproves of the other girls' cruel behavior.
Mame Dennis (Rosalind Russell), a progressive and independent woman of the 1920s, is left to care for her nephew Patrick (Jan Handzlik/Roger Smith) after his wealthy father dies.
Tootsie (1982)
New York actor Michael Dorsey (Dustin Hoffman) is a talented perfectionist who is so hard on himself and others that his agent (Sydney Pollack) can no longer find work for him.


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La Copa de Clubes de Asia 1971 fue la cuarta edición de la Liga de Campeones de la AFC. Se disputó entre el 21 de marzo y el 2 de abril de 1971, en la ciudad de Bangkok. Participaron ocho equipos. En la final del torneo, Al-Shorta, uno de los finalistas, desistió de jugar frente a Maccabi Tel Aviv FC, (debido a motivos políticos, por la guerras entre las naciones árabes con Israel) haciendo que este último fuese el campeón por walkover. De esta forma, Maccabi Tel Aviv FC obtuvo su segundo título en este evento.

Fase previa
Esta fase tuvo el objetivo de definir los integrantes de los grupos de competencia. Así, cada grupo fue compuesto por dos equipos ganadores y dos equipos perdedores de esta fase.

Primera fase

Grupo A

Grupo B

1: Al-Shorta desistió de jugar frente a Maccabi Tel Aviv.

Segunda fase

Campeón

Referencias

Enlaces externos
 Copa de Clubes de Asia 1971 en RSSSF

1971
Fútbol en 1971

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