A treatise on the origin, progressive improvement, and present state of the manufacture of porcelain and glass (1832)
[Porter, George Richardson], 1792-1852. [from old catalog] · Philadelphia, Carey & Lea · leaf 60
esigned for the introduction of trialpieces within the kiln: another similar opening is left when CHAP. V. OF FIRING AND GLAZING. 59 walling up the door-way E. The whole of these are providedwith clay stoppers which exactly fill the holes, and which haveprojections whereby they can be removed or… … holes, placed over the openings F. These air-holes serve todivide the draught, and consequently to equalize the tempera-ture of the kiln. I is a round iron plate, supported on fourpillars of the same metal, and placed over the chimney to de-fend the opening. When the firing has been sufficiently…
Porcelain · Glass manufacture
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