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1. Introduction: the concept of conservation and ethical principles
1.2. Preservation criteria
1.3. Restoration criteria
In general terms, conservation may be defined as the operations which together are intended to prolong the life of an object by forestalling damage or remedying deterioration.
In the domain of cultural property, the aim of conservation is to maintain the physical and cultural characteristics of the object so as to ensure that its value is not diminished and that it will outlive our limited time span.
This type of conservation is based on the principle that all moveable cultural property - the objects with which we are concerned in these pages - possesses a physical or corporeal nature, a support, and in the case of graphic documents, support-based elements which carry the particular message of that document.
By its very nature, this type of object demands a conservation process that will ensure its physical as well as its functional integrity: the former is concerned with the preservation of the material components of the document while the latter is concerned with its capacity to transmit the information it possesses. That is to say, if the material appearance of a document is intact but the transmission of the original content is lost or endangered it cannot be considered to be in a good state of conservation. Conversely, if the content remains but the physical make-up of the graphic document is so fragile or debilitated that transmission of the idea or the cultural value it contains is hampered, then the document can no longer fulfil its function. Consequently, the conservation of a graphic document - whether a book, a page, any written material, or drawing which are included under this head must maintain the permanence and durability of the object in question.
Permanence refers to the conservation of its physical nature and durability to the capacity to transmit information. Documentary integrity is achieved only when the material is conserved. An optimum degree of conservation is ensured with the harmonious achievement of physical and functional integrity.
There are two types of action in the conservation of materials:
(a) Preventing deterioration (preservation)
(b) Repairing damage (restoration)
These procedures are complementary but it must be borne in mind that restoration is the consequence of inefficient, or lack of preventive measures.
In order to ensure that both preventive measures and restoration techniques are properly carried out, there is a need for certain rules which will unify criteria and ensure that the procedures carried out on the work as a material object do not result in the loss of its cultural value. These guide-lines must discard procedures such as those - whose aim is purely lucrative - which turn restoration into faking and camouflage; at the other extreme, they must avoid excessive zeal which misinterprets preservation as total restriction of use and considers that the only conservation method is prevention, reflecting restoration totally.
In order to avoid operations of this kind and to unify criteria concerning procedures, true professionals carry out their work according to a set of rules which guide the correct application of preventive or restoration methods. Although the guide-lines laid down are flexible as regards their adaptation, they must be rigidly observed, the intention being always to safeguard the integrity of cultural values.
In the face of past anarchy, experts in the various domains connected with cultural property have, at international meetings and congresses, expressed their desire to adopt a common response in the solution of problems of interest to all. Unesco's backing has represented a landmark with the establishment of generally accepted standards whereby the objects that bear witness to a culture are regarded as the invaluable heritage of all humankind.
Current conservation criteria which have emerged from these debates may be summed up in the following principles which are in keeping with the objectives that reflect the distinction between restoration and preservation:
1.2. Preservation criteria
The aim of preservation is to obviate damage liable to be caused by environmental or accidental factors which pose a threat in the immediate surroundings of the object to be conserved. Accordingly, preventive methods and measures are not usually applied directly but are designed to control the microclimatic conditions of the environment with the aim of eradicating harmful agents or elements which may have a temporary or permanent influence on the deterioration of the object.
Damage by external factors extraneous to the nature of the object to be conserved which, in the long or short term, would affect its cultural value, must be guarded against.
Having regard to the conditions of stability and availability which these objects must fulfil, the criteria draw attention to the need to:
1. Create an environment conducive to permanence and durability, and to take whatever steps may be necessary to tackle the causes of alteration without damaging the work or works to be protected either directly or indirectly.
This principle implies prior knowledge of:
(a) The physical and chemical behaviour of the structure and the components of the materials to be conserved.
(b) Potential causes of deterioration.
2. Provide protection against deterioration should indiscriminate use represent a threat to the cultural integrity of the work by:
(a) Restricting use to those who, because of their cultural work, are required to handle the object directly.
(b) Providing a replica which, without detracting from the merits of the original or involving any fraudulent practice, will satisfy curiosity or research requirements.
1.3. Restoration criteria
The aim of restoration is to re-establish the physical and functional integrity of a work by remedying the alterations which it may have undergone.
Curative measures are, therefore, applied directly with the aim of repairing the damage that the work may have sustained during its existence, when such damage involves mutilation or detracts from the documentary value of the work.
Direct application implies an enormous responsibility both vis-à-vis the work itself and the particular period of history to which it undoubtedly belongs and of which it is an integral part.
Restoration demands, above all, a spirit of renunciation and great respect - renunciation of all creative participation and respect, great respect for the work of the author and what he or she wished to transmit. For these reasons, restoration is more a technique than an art thanks to the range of interdisciplinary scientific methods which ensure that the work carried out is backed by the strict precision of the sciences applied to conservation procedures.
The similarity of the responsibilities assumed by medicine and conservation cannot be defined, particularly as regards their mutual desire to transcend the natural limits of the human race and its works. Restoration therefore adopts as its own the watchword of the science and art of medicine: above all not to cause worse ills ("primum non nocere") nor to apply any treatment without prior analysis ("there are no illnesses, only patients").
Restoration provides a response that is fully in keeping with these principles by means of its analytical approach aimed at ascertaining metaphysical and physical values. Having regard to the foregoing it is necessary to:
1. Recognize and assess the total integrity of the work, which implies:
(a) Identification of its documentary value:
(b) Identification of the characteristics and properties of the materials of which it is made;
(c) Structural analysis of all the elements which make up the whole;
(d) Definition in time and space of the historical period in which it was created and of possible additions;
(e) Objective assessment of all the physical or functional modifications which it has undergone.
2. Critical appraisal (diagnosis) of the state of conservation, determining:
(a) Causes of alterations;
(b) Physical and functional damage or effects.
3. Definition of the treatment to be applied in accordance with the data obtained from the previous studies.
This analytical approach which, with the aid provided by the corresponding applied sciences, precedes any restoration work, is followed by the application of restoration measures and procedures. The criteria which must govern restoration per se are set out below:
1. Renunciation of any treatment demanding technical and human resources that exceed available possibilities.
2. Avoidance of any processes which imply real or apparent modification of the authentic values specific to the work.
3. Respect for any complementary additions which are an inseparable part of the history of the cultural object itself.
4. Elimination of any kind of masking, alien to the total integrity of the work, which affects its interpretation as a historical document or renders such interpretation impossible.
5. Stabilization and consolidation of the elements that have suffered deterioration instead of their removal or replacement.
6. Re-insertion of the elements which are physically separated from the rest of the work and which obviously form apart of the whole.
7. Reconstruction of missing elements when the gaps are identifiable. In this case materials of recognized quality should be used which, when incorporated into the work, will be easily identified as not forming an integral part of the original.
8. Replacement of unidentifiable elements when their presence is necessary for the understanding or physical preservation of the work, using techniques, materials and forms whose neutral characteristics will both harmonize with and differ from the original structure and specific style of the whole.
9. Carrying out of all restoration operations with the use of procedures which, from the standpoint of harmlessness and reversibility, will be determined by the characteristics of the work.
10. The recording of all restoration work in an exhaustive dossier.
Following the general principles outlined above, it should be stressed that the concept of conservation covers both restoration curative procedures in respect of damage which is already apparent - and preservation - the best form of conservation, consisting of preventive action designed to forestall and prevent the processes which lead to alteration. If preservation is effective there will be no need for restoration, a procedure which directly affects the nature of whatever may remain of the real object, whether this is considerable or very little.
Finally, and before the subject of this study is tackled in detail, it should be pointed out that no one can learn restoration solely from applying what is contained in these or any other pages; neither should restoration be based on empirical methods, whose reliability has not been verified. Restoration demands sound training, a continuous learning process, and the scientific, technical and advisory back-up of a complex team. It requires a good dose of knowledge of the nature and behaviour of the materials to be treated and used, as well as a highly developed sense of responsibility. The restorer must be receptive to criticism; to which the process of 'acting for the best' may give rise, aware that the values inherent in any cultural object are irreplaceable and that all restoration work always involves potential risk.
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