Plaster of Paris or Stucco
Although plaster of Paris is widely used today its origins date back to more than 9000 years ago. Anatolia and Syria are regarded as being the birthplace of this beneficial substance. About 5000 years ago the Egyptians started making their own version of the plaster of Paris. They would heat gypsum in open-air fires and then crushed it to make it into a powder form. This would then be mixed with water in order to serve as the jointing material for their bricks and blocks.
The ancient Greeks have also experimented with gypsum to create something like plaster of Paris. They would use it for creating windows in their temples. The kind of plaster they used was in its transparent form. Similarly the Romans made use of plaster of Paris to cast statues. With the passage of time many different civilizations experimented with gypsum calcinations and much expertise was gained through trial and error. By the1700s the city of Paris had become the center for this kind of plaster.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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