A fine feldspathic earthenware including a body and a glaze layer covering surfaces of the body. The body has water absorption percentage of not lower than 3% and lower than 15% and includes an annular bottom formed on a bottom portion of the body. The glaze layer is absent on a surface of the annular bottom, and the surface of the annular bottom is covered with an annular vitrified layer which has substantially no water absorbing property. The vitrified layer is formed by coating the surface of the annular bottom with a composition having lower refractoriness than the body, and biscuit-firing the composition together with the body.

 
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> High altitude parachute navigation flight computer

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