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This reacts with the chloride ions to stop them reacting further.
Vegetable tanned leathers are susceptible to sulphur pollution and form a fragmentary fibrous red material called red rot. The leather needs to be stabilised by applying chemicals. As an interesting aside, the scientist Michael Faraday, who did much of the pioneering work on electricity, also worked on this problem, so we like to claim him as one of us too.
Another 19th century conservation discovery is Bryne's disease. Bryne discovered that sea shells can react with the organic acids emitted from wood and turn chalky (Bryne, 1899).
Analyses of artefacts
The third aspect of the profession is that we can study the object scientifically to study how it was made or how it is degrading. The instruments of research our section have include ultraviolet and infrared lights to detect under-layers of paint. A photo-spectrometer measures colours and gives a colour three numbers. This is useful for studying decay and testing how close colour matched paint is to the original. A metallographic polisher can prepare cross sections through specimens of metals, ceramics, stones and wood to help in the identification of materials and to study the manufacturing technology. The section also has three X-ray machines. Incidentally, this is not extravagance by the government. Each performs a different rôle in terms of size and the voltage at which it operates.
The section recently took delivery of an infrared analyses machine. This helps identify organic materials. IR radiation is fired at a tiny organic sample of a glue, resin or wax-like substance that is under analysis. Each chemical substance absorbs a typical spectrum of radiation; so by comparing the radiation absorbed by the material with a library of results, an identity for the substance can be determined.
Conservators are very skilled individuals. Ideally, we should be scientific craftsmen with an interest in history/art. We can also, through conservation, invoke a wide variety of other disciplines such as anthropology, botany, ceramic science, dating techniques and electroplating, through to zoology