Analyses of Henry III 1272 Charter

Delmina Barros| June 13, 2021

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Materials and manufacture The charter is constituted by the parchment (where the message is written, the seal and the thread that attaches the royal seal to the parchment (see figure 1 above)(Beirne R. 2019/20)

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Parchment Parchment, a writing material made from prepared untanned skins of animals—primarily sheep, calves, and goats. It has been used as a writing medium for over two millennia.   In order to make the parchment more aesthetically pleasing or more suitable for the scribes, unique treatments were used, like powders and pastes, to help remove grease so the ink would not run. (figure 2). 

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Parchment a material consists of collagen fibre, a 13% water content and 1.6% residual lime. Collagen bonds easily with water molecules, leaving parchment particularly sensitive to the presence of water. Therefore, it is vulnerable to a high or fluctuating RH, rapidly absorbing water in high humidity and losing it as the humidity is lowered. These changes cause the parchment to expand and contract, causing objects to become deformed (Woods 2006)(Beirne R. 2019/20)

The parchment in this charter is in good condition, although on the surface suggests that it has been exposed to a fluctuating RH. ​The surface has become worn in some areas( see figure 3 and 4), with exposed corners being particularly vulnerable. It is also here where we see the most visible patches of ingrained dirt and discolouration, as particulates of dirt have become trapped in the creased surface(Beirne R. 2019/20).

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Ink

The condition of the ink requires ongoing assessment. Ink cracks as the parchment swell and shrinks during RH fluctuations and can be quickly lost to flaking. Therefore, control points across the document should be photographed and monitored, with images compared each year. The risk of ink loss is heightened in the areas that are cockling and folding, where the parchment becomes distorted and creased (Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20).

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There is an additional risk to the legibility of the document, with the iron gall ink itself liable to corrosion and causing damage to the parchment (The Iron Gall Ink Website 2020)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20).  Fortunately, the charter shows little sign of damage in terms of the ink corroding through the parchment – iron gall ink can be stable over long periods, but conservators should be aware of the risks and the need to control the storage environment(Beirne R. 2019/20). Much of the charter’s original writing appears in good condition with minimal flaking (Beirne R. 2019/20) A Dino-Lite image taken with visible light showing the condition of the writing (see figure 5 below)

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Condition Assessment

Overall the 1272 charter is in stable condition and in order not to deteriorate further, it needs to be kept in appropriate conditions. Transportation is cause for concern, and great potential for parchment, seal and cords to move independently causing damage, and the ink condition will require ongoing assessment as outlined above. However, despite some deterioration, the charter is mainly intact, there is no active corrosion from the iron gall ink, and the lettering remains legible(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20)

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Preventive Conservation

It is important to establish controls for the storage environment, because of the vulnerabilities of each material. To conserve parchment, relative humidity (RH) should be maintained between 45 and 60% to avoid mould growth, and fluctuations in RH and temperature must be reduced to prevent dimensional changes. If on display, light levels should be kept below 50lux to reduce fading of pigments in the ink and textiles and filtered for UV (Woods 2006). While in storage, the charter should not be exposed to light and should be kept in custom packaging of buffered, acid-free cards to immobilise all elements during transportation, and handling should be minimised to lower the risk of accidental damage(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20)

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Royal Seal

A seal attached to a document indicates one’s authorisation of the contents. At the time of the Charters drafting, it also functioned as evidence of the document’s authenticity as well as rendering its written terms unquestionable (Burns 1998)(Beirne R. 2019/20)

A seal attached to a document indicates the authorisation of the contents. At the time the Charters was created, it also functioned as evidence of the document’s authenticity as well as rendering its written terms unquestionable (Burns 1998)(Beirne R. 2019/20) The seal attached to the Charter by braided cords hanging down (see figure 2) the lower edge is one of the Great Seals of England, the symbol of the office of the Chancellor of the Exchequer. And when attached to a document represents the approval of the Sovereign of the day(Beirne R. 2019/20) The impression of the Seal wields great power and authority and, as a result, has always had two sides ( see figures 5 and 6), but also obliges the need for it to hang from documents so that both sides can be inspected, (Burns 1998)(Beirne R. 2019/20)

The 1272 Charter of Henry III is significant among the charters collection as it granted the citizens of Lincoln a legal place, the Guildhall, to make their pleas.  A detailed examination of the Seal attached to the Charter and the cord used to secure it reveals some interesting details to our understanding of the document(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20) 

The seal attached to this  Charter is that of Henry III even though it is difficult to identify it as such because many of the original is missing. As per figures 6 and 7, the seal has been restored as most of it had been damaged and lost. 

Several studies of medieval English wax seals have revealed that they usually consist of only beeswax Young et al., 1987)(Beirne R. 2019/20)  In these same studies, it was noted that while there was very little chemical change to the waxes compared with later resin compositions, the soft nature of the beeswax had resulted in physical alterations and damage to some seals(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20)  The repairs may have been carried out in this distinctly noticeable manner (see figure 6 and 7) (figure 8and 9) because attempting to replicate the original colour and design could have been interpreted by later generations as an attempt of forgery or questioned the legitimacy of the charter. By making all repairs distinguishable from the original seal, the legal integrity of the seal has been maintained (Burns 1998)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20) 

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The seal shows no signs of biological attack and does not appear to be in immediate danger of deterioration, but requires careful handling due to the nature of the material(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20). Although the cords appear intact there are numerous breakages of individual threads when examined using a Dino-Lite ( see figures 10 and 11 below), which is a sign of deterioration. 

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Experimental testing of historic silk fibres suggests that high temperature and RH accelerates deterioration (Luxford et al. 2019), and as previously mentioned, should be stored in a controlled environment with minimal handling in order to avoid placing mechanical stress on the threads(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20).

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Thread/Cords There are different methods used to attach a Seal to a document. 

Having said that, the three-eyelet lace method used in this charter (see figure 12) was one of the most elaborate. The Royal Chancery was often used in medieval times to represent the greater importance of royal documents intended for perpetual use, such as a charter, compared to documents that were of temporary value, such as letter patents or letters close (Dalton 1992)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20). Making this method more robust than the other sealing methods, to ensure the documents survival. The bottom of the parchment underneath the writing is folded over to create a double thickness, called a plica (Burns 1998), from which to suspend the wax seal (Maxwell-Lyte 1926)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20) 

The two cords, usually braided in different colours, are threaded through the eyelets in the sequence demonstrated in figure 12, after which the seal is affixed to the cord in the method described below (Burns 1998) (Beirne R. 2019/20).  Both coloured laces are individually braided using a finger loop method(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20). 

Following the threading of these individual laces through the parchment eyelets, as mentioned above, the two laces become four and are braided together and tied at the end with a knot (Dalton 1992) (Beirne R. 2019/20). The braid would have been placed between two layers of warm wax with its end passing through its bottom. The layers of wax were fused into one by pressing them between the two sides of the silver seal matrix, the metal mould which creates the seal impression (Burns 1998) (see figures 13 and 14)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20) 

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When attached to documents, the orientation of the Great Seal was quite specific; the head of the sovereign had to be perpendicular to the writing on the parchment on both sides of the seal. On the front of the seal, the side facing upwards with the document’s text represents the sovereign enthroned, while on the reverse, they are displayed heading the military or naval forces, usually astride a horse (Maxwell-Lyte 1926)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20).

The cords used to affix the seal are green and pink (see figures 13 and 14). Green and red are noted as a popular choice (Maxwell-Lyte 1926), and it is possible that the pink cord of this Charter was originally a red that has now faded from photodegradation(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20).

Other features of the Charter such as the method of sealing and the colour of the wax used have specific administrative significance, it is purported that the colour of the laces used to attach the Great Seal was completely arbitrary, though the use of two different colours did seem to be a standard feature, (Maxwell Lyte 1926)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20).

In this case, the royal seal appears to have been attached incorrectly, possibly done by mistake during the previous restoration (see figure 15 and 16 below).

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Digital Recording Techniques

The investigation into an object requires detailed records to enable current and future researchers and conservators the continuing examination without handling the artefact.

Photography

Photographs give details of an object’s form. In the photographs produced, we can identify the charter’s features and divide it in three main material components – the parchment(with many details in the writing), the silk cords and wax seal( see figures 14 and 15)(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21](Beirne R. 2019/20).

By using digital recording techniques, like RTI and Photogrammetry, different structural differences will be captured in comparison to regular photographs(Investigating the Lincoln Charters. Available from: https://mairtrueman.wixsite.com/thechartersproject [assessed 11-06-21] (Beirne R. 2019/20).

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Ultraviolet (UV) photograph

UV analyses helps identify previous restoration by highlighting the areas retouched in a darker purple hue, and in this case, there were a couple of areas that showed the previous retouching (figures 17, 18 and 19 below).

This analysis shows a possible retouching in the seal area, highlighted in dark purple (see figure 19 left). The parchment did not show sign of the previous retouch but highlighted the tear mending previously done see figure 18).

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X-ray (radiography): Imaging technique to view the internal structure of an object and it is:

• Non-destructive
• Traditionally used for metals, but with the right settings, it can be possible to see textiles (stitching and weave of fabrics), wood, certain pigments, ceramics, bone.
• The size of the x-ray cabinet available limits the size of objects for study available.

An x- ray of the seal revealed the mechanics of the repairs; in figure 20 (on the left), the parchment part of the charter did not show any hidden structure condition. On the other hand, the x-ray done on the seal (figure 21 on the right) showed possible internal cracks and enhanced the previously restored areas.  

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Infra-red photography

Infrared imaging helps identify any underdrawings as part of the artist drawing and preparation.

Under infra-red photographs it was revealed the underlines place in the parchment before writing (figure 24 top right) .

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X-Ray Fluorescence Spectroscopy (XRF): a technique for elemental and chemical analysis

This analyses is:

• Non destructive
• Surface technique
• Elemental composition
• Identification of inorganic composition (metals, ceramics, glass, stone, mortar, inorganic pigments)

Tests were made in the charter’s ink, and the XRF results are consistent with iron gall ink, with high concentrations (Conc. [%] in the table below) of sulphur (44.02%) and iron (12.64%) (see figure 25 below).

Ink

Iron gall ink has been used since the 5th Century AD up to the 20th Century. Whic makes it reasonably to expect its use on a 13th Century document, and the charter’s XRF results support this prediction.

Iron Gall Ink Production: There are many iron gall ink recipes. However, four primary ingredients remain constant: tannin, vitriol (iron sulphate), Gum Arabic and water. Tannin was extracted from tree galls (a growth resulting from insect larvae hatching within tree bark). In contrast, vitriol could be extracted from mines or obtained as a byproduct of alum manufacturing (often contaminating the ink with aluminium), and Gum Arabic was taken from Acacia trees. A range of other ingredients could be added to alter the ink’s properties, such as indigo to change the colour or brandy to prevent it from freezing. Generally, manufacture consisted of crushing tree galls and combining this with liquid vitriol and Gum Arabic (The Iron Gall Ink Website 2020).

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Digital Techniques

RTI (Reflectance Transformation Imaging)

The use of computer software, revealing an object’s surface shape and distortions. 

For RTI, by the combination of a series of photographs, each lit from a different angle (Cultural Heritage Imaging 2020). 

This process allows the re-light of the charter from any direction, picking out details that are easier seen under raking light, particularly the condition of the parchment, folds and creases in its surface, and how these folds would have been layered when closed (see figure 25). Another feature of RTI is the Normals Visualisation, which gives a false-colour version of the object, highlighting the seal’s contours (see figure 26).

This method is:

• Non-invasive re-coding method (non-contact)
• Surface texture is captured
• It uses a series of digital photographs under various light angles
• Access to RTIBuilder software is required to process the image

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Photogrammetry

Photogrammetry software aligns several overlapping photographs, with the camera rotated around the object for each photograph, reconstructing the object’s 3D measurements to produce an interactive model (Cultural Heritage Imaging 2020). The textural information captured through this technique is less detailed than the ones previously mentioned, but it has the advantage of enabling the viewer to circle the virtual model as they would a physical artefact. This technique is beneficial for this charter has it highlights the depth of features impressed into the wax seal, lending more solidity to the object and depicted figures (see figures 27 and 28).

This technique is:

• Non-invasive method (non-contact)
• Used as a documentation and recording technique
• It uses a series of digital photographs – the camera is moving around the imaging subject
• A textured 3D model is generated
• Access to photogrammetry software is required to process the images

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For more information on the topics discussed, please see the resources referenced here:

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