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Typically parchment made from calfskin is called vellum, though the term can also be used to refer to very fine quality parchment made from the skins of other animals. For the purposes of conservation and restoration, the term parchment is used in reference to vellum objects, as the terms have been used interchangeably throughout time to refer ...
Parchment is also extremely affected by its environment and changes in humidity, which can cause buckling. Books with parchment pages were bound with strong wooden boards and clamped tightly shut by metal (often brass) clasps or leather straps; [20] this acted to keep the pages pressed flat despite humidity changes. Such metal fittings ...
Its production began around the 3rd century BCE. Made using the skins of animals (sheep, cattle, donkey, antelope, etc.), parchment proved to be easier to conserve over time; it was more solid and allowed one to erase text. It was a very expensive medium because of the rarity of the material and the time required to produce a document.
Prior to this time, many physicians believed that microorganisms were spontaneously generated, and disease was caused by direct exposure to filth and decay. Koch helped establish that the disease was more specifically contagious and was transmittable through the contaminated water supply. The fifth was the last serious European cholera outbreak ...
A conservation technician examining an artwork under a microscope at the Indianapolis Museum of Art. The conservation and restoration of books, manuscripts, documents, and ephemera is an activity dedicated to extending the life of items of historical and personal value made primarily from paper, parchment, and leather.
However, large numbers of silkworms began dying from diseases and the French government asked Pasteur to investigate the problem. [56] Pasture connected the disease in silk worms known as pébrine to the parasite Nosema bombycis. The other disease called flacherie caused silkworms to become dark brown. Pébrine was thought to be a form of ...
Louis Pasteur ForMemRS (/ ˈ l uː i p æ ˈ s t ɜːr /, French: [lwi pastœʁ] ⓘ; 27 December 1822 – 28 September 1895) was a French chemist, pharmacist, and microbiologist renowned for his discoveries of the principles of vaccination, microbial fermentation, and pasteurization, the last of which was named after him.
Though the pathology of contagion was understood by Muslim physicians since the time of Avicenna (980–1037) who described it in The Canon of Medicine (c. 1020), [6] the first physician known to have made postmortem dissections was the Arabian physician Avenzoar (1091–1161) who proved that the skin disease scabies was caused by a parasite ...