This section is from the book "The Engineer's And Mechanic's Encyclopaedia", by Luke Hebert. Also available from Amazon: Engineer's And Mechanic's Encyclopaedia.
The name given to a kind of earth, which forms one of the ingredients in the manufacture of oriental porcelain. The other ingredient, which is called petuntse, is easily vitrifiable, while kaolin is scarcely so; hence, it is said, the action of the fire upon the mixture causes that semi-vitrification called porcelain. M. Bomare, who analysed some Chinese kaolin, states its composition to be a compound earth, consisting of clay, to which it owes its tenacity; of calcareous earth, whence its mealy appearance; and of crystals of mica and quartz. Similar earths to the kaolin are often found in the neighbourhood of granites.
 
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