Principle of physics according to which the energy of interacting bodies or particles in a closed system remains constant, though it may take different forms (e.g., kinetic energy, potential energy, thermal energy, energy in an electric current, or energy stored in an electric field, in a magnetic field, or in chemical bonds [see bonding]). With the advent of relativity physics in 1905, mass was recognized as equivalent to energy. When accounting for a system of high-speed particles whose mass increases as a consequence of their speed, the laws of conservation of energy and conservation of mass become one conservation law. Seealso Hermann von Helmholtz.
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Product of the mass of a particle and its velocity. Newton's second law of motion states that the rate of change of momentum is proportional to the force acting on the particle. Albert Einstein showed that the mass of a particle increases as its velocity approaches the speed of light. At the speeds treated in classical mechanics, the effect of speed on the mass can be neglected, and changes in momentum are the result of changes in velocity alone. If a constant force acts on a particle for a given time, the product of the force and the time interval, the impulse, is equal to the change in momentum. For any array of several objects, the total momentum is the sum of the individual momenta. Seealso angular momentum.
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Property that describes the rotary inertia of a system in motion about an axis. It is a vector quantity, having both magnitude and direction. The magnitude of the angular momentum of an object is the product of its linear momentum (mass math.m × velocity math.v) and the perpendicular distance math.r from the centre of rotation, or math.mmath.vmath.r. The direction is that of the axis of rotation. The angular momentum of an isolated system is constant. This means that a rigid spinning object continues to spin at a constant rate unless acted upon by an external torque. A spinning gyroscope in an airplane remains fixed in its orientation, independent of the airplane's motion, because of the conservation of direction as well as magnitude.
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In physics, the principle that certain quantities within an isolated system do not change over time. When a substance in an isolated system changes phase, the total amount of mass does not change. When energy is changed from one form to another in an isolated system, there is no change in the total amount of energy. When a transfer of momentum occurs in an isolated system, the total amount of momentum is conserved. The same is true for electric charge in a system: charge lost by one particle is gained by another. Conservation laws make it possible to predict the macroscopic behaviour of a system without having to consider the microscopic details of a physical process or chemical reaction.
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Planned management of a natural resource or of a particular ecosystem to prevent exploitation, pollution, destruction, or neglect and to ensure the future usability of the resource. Living resources are renewable, minerals and fossil fuels are nonrenewable. In the West, conservation efforts date to 17th-century efforts to protect European forests in the face of increasing demands for fuel and building materials. National parks, first established in the 19th century, were dedicated to the preservation of uncultivated land not only to provide a safe haven to wildlife but to protect watershed areas and help ensure a clean water supply. National legislation and international treaties and regulations aim to strike a balance between the need for development and the need to conserve the environment for the future.
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Maintenance and preservation of works of art, their protection from future damage, deterioration, or neglect, and the repair or renovation of works that have deteriorated or been damaged. Research in art history has relied heavily on 20th- and 21st-century technical and scientific advances in art restoration. Modern conservation practice adheres to the principle of reversibility, which dictates that treatments should not cause permanent alteration to the object.
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(1933–42) U.S. unemployment program. One of the earliest New Deal programs, it was established to relieve unemployment during the Great Depression by providing national conservation work primarily for young unmarried men. Recruits lived in semimilitary work camps and received $30 a month as well as food and medical care. Projects included planting trees, building flood barriers, fighting forest fires, and maintaining forest roads and trails. It employed a total of 3 million men during its existence.
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Art conservation is a profession devoted to the preservation of cultural heritage for the future. Conservation activities include examination, documentation, treatment, and preventive care. All of this work is supported by research and education.
The traditional definition of the role of the conservator involves the examination, conservation, and preservation of cultural heritage using "any methods that prove effective in keeping that property in as close to its original condition as possible for as long as possible.”
However, today the definition of the role of conservation has widened and would more accurately be described as that of ethical stewardship.
The conservator applies some simple ethical guidelines, such as:
The conservator aims to take into account the views of the stakeholder and to apply their professional expertise accordingly .
The conservator's work is guided by ethical standards. These take the form of applied ethics. Ethical standards have been established across the world, and national and international ethical guidelines have been written. One such example is:
Conservation OnLine's Ethical issues in conservation provides a number of articles on ethical issues in conservation; example of codes of ethics and guidelines for professional conduct in conservation and allied fields; and charters and treaties pertaining to ethical issues involving the preservation of cultural property.
The profession of art conservation is broad and encomposses many areas of speciality. Some specialities within art conservation would include:
Interventive Conservation refers to any act by a conservator that involves a direct interaction between the conservator and the cultural material. These interventive treatments could involve the cleaning, stabilizing, repair, or replacement of parts of the cultural material. It is essential that the conservator fully justify any such work, as well as fully documenting the work both before, during, and after the treatment.
The principal goal should be the stabilisation of the object or specimen. All conservation procedures should be documented and as reversible as possible, and all alterations should be clearly distinguishable from the original object or specimen.
This page contains a list of some of the key dates in the history of conservation in Europe and the United States, compiled by Joyce Hill Stoner. Beginning in 1565 with the restoration of the Sistine Chapel frescoes.
The care for cultural patrimony has a long history within traditions of fixing and mending objects, and in individual restorations of artworks. However, perhaps the first organised attempt to conserve cultural patrimony was the Society for the Protection of Ancient Buildings in the UK, influenced by the writings of John Ruskin the society was founded by William Morris and Philip Webb in 1877. During the same period a movement with similar aims had also developed in France under the direction of Eugène Viollet-le-Duc a French architect and theorist, famous for his "restorations" of medieval buildings.
Conservation developed as a distinct field of thought initially in Germany, when in 1888 Friedrich Rathgen became the first Chemist to be employed by a Museum, the Koniglichen Museen, Berlin (Royal Museums of Berlin). He not only developed a scientific approach to the care of objects in the collections, but disseminated this approach publishing a "Handbook of Conservation" in 1898. The early development of conservation in any area of the world is usually linked to the creation of positions for chemists within museums. In 1924 in the UK the chemist Harold Plenderleith began to work at the British Museum with Dr. Alexander Scott in the newly created Department of Scientific and Industrial Research, thus giving birth to the conservation profession in the UK. This department had been created by the museum to address objects in the collection that had begun to rapidly deteriorate as a result of being stored in the London Underground tunnels during the First World War. The development of this department at the British Museum moved the focus for the development of conservation from Germany to Britain, and in 1956 Plenderleith wrote a significant handbook called The Conservation of Antiquities and Works of Art, it was this book rather than Rathgen's that is commonly seen as the major source for the development of conservation as we know it today.
In the United States the development of conservation can be traced to the Fogg Art Museum, and Edward Waldo Forbes, the Director of the Fogg from 1909 to 1944. He encouraged technical investigation, and was Chairman of the Advisory Committee for the first technical journal, Technical Studies, in the Field of the Fine Arts, published by the Fogg from 1932 to 1942. Importantly he also brought onto the museum staff chemists. Rutherford John Gettens was the first chemist in the U. S. to be permanently employed by an art museum. He worked with George L. Stout, the founder and first editor of Technical Studies. Gettens and Stout co-authored Painting Materials: A Short Encyclopaedia, first published in 1942 and reprinted in 1966. This compendium is still cited regularly. Only a few dates and descriptions in Gettens’ and Stout’s book are now outdated.
The focus of conservation development then accelerated in Britain and America, and it was in Britain that the first International Conservation Organisations developed. The International Institute for Conservation of Historic and Artistic Works (IIC) was incorporated under British law in 1950 as “a permanent organization to co-ordinate and improve the knowledge, methods, and working standards needed to protect and preserve precious materials of all kinds.” The rapid growth of conservation professional organizations, publications, journals, newsletters, both internationally and in localities, has spearheaded the development of the conservation profession, both practically and theoretically. Art historians and theorists such as Cesare Brandi have also played a significant role in developing conservation-restoration theory. In recent years ethical concerns have been at the forefront of developments in conservation. Most significantly has been the idea of Preventive conservation. This concept is based in part on the pioneering work by Garry Thomson CBE, and his book the Museum Environment, first published in 1978. Thomson was associated with the National Gallery (London), it was here that he established a set of guidelines or environmental controls for the best conditions in which objects could be stored and displayed within the Museum Environment. Although his exact guidelines are no longer rigidly followed they did inspire this field of conservation.
During the nineteenth century, the fields of science and art became increasingly intertwined as scientists such as Michael Faraday began to study the damaging effects of the environment to works of art. Louis Pasteur carried out scientific analysis on paint during this time period as well.
Today, conservators routinely use chemistry and scientific analysis for the examination and treatment of cultural works. The modern conservation lab uses equipment such as microscopes, spectrometers, and x-ray machines to better understand and assess objects and their components.
In October 2006, the Department for Culture, Media and Sport, a governmental department, authored a document: "Understanding the Future: Priorities for England's Museums" This document based on several years of consultation aimed to lay out the governments priorities for museums in the 21st Century.
The document listed the following as priorities for the next decade:
1. Museums will fulfil their potential as learning resources (pp 7-10).
2. Museums will embrace their role in fostering, exploring, celebrating and questioning the identities of diverse communities (pp 11-14).
3. Museums’ collections will be more dynamic and better used (pp15-18).
4. Museums’ workforces will be dynamic, highly skilled and representative (pp 17-22).
5. Museums will work more closely with each other and partners outside the sector (pp 23-26).
The conservation profession response to this report was on the whole less than favourable, the Institute of Conservation (ICON) published their response under the title "A Failure of Vision. It had the following to say:
"No sector can look with confidence to the future if its key asset is worked harder and harder across an ever broadening range of objectives while the inputs required to sustain it are neglected."
"It is of major concern to us that the only part of this section which makes any acknowledgement of the need for greater resourcing is the part which refers to acquisitions. The original consultation paper made quite extensive reference to the importance of collections, the role of new technologies, and cultural property issues, but this appears to have been whittled away in the present document."
"When asked by the Commons Culture Media and Sport elect Committee CMS committee what he would like to see as a priority in the DCMS document arising from the ‘Understanding the Future’ consultation, Mr MacGregor responded ‘I would like to see added there the need to conserve and research the collections, so that the collections can really play the role across the whole of the United Kingdom that they should.’ So would we."
The University can rarely provide all the necessary training in first hand experience that an apprenticeship can, and therefore in addition to graduate level training the profession also tends towards encouraging conservation students to spend time as an intern.
Conservation is an Interdisciplinary field as conservators have backgrounds in the fine arts, sciences (including chemistry, biology, and materials science), and closely related disciplines, such as art history, archaeology, studio art, and anthropology. They also have design, fabrication,artistic, and other special skills necessary for the practical application of that knowledge.
Within the various schools that teach conservation, the approach differs according the educational and vocational system within the country, and the focus of the school itself. This is acknowledged by the American Institute for Conservation who advise "Specific admission requirements differ and potential candidates are encouraged to contact the programs directly for details on prerequisites, application procedures, and program curriculum".
The built heritage was also at the forefront of the growth of member based organizations in the United States for example, founded in 1889, the Richmond, Virginia-based Association for the Preservation of Virginia Antiquities was the United States' first statewide historic preservation group. In 2003 it changed its name to reflect its wider focus in statewide preservation issues.
Today, professional conservators join and take part in the activities of numerous conservation associations and professional organizations with the wider conservation field, and within their area of specialization.
These organizations exist to "support the conservation professionals who preserve our cultural heritage".
This involves upholding professional standards, promoting research and publications, providing educational opportunities, and fostering the exchange of knowledge among conservators, allied professionals, and the public.