Society of Glass Technology · [Sheffield] · leaf 575
11, 12, whichare bolted to columns, 5, builtinto a fire-brick lining, 4.The furnace is preferably ofcircular shape with an outermetal shell, 2, a brick wall, 1,and an interposed layer, 3. ofpulverulent heat - insulatingmaterial. Insulated leads, 16,pass through the wall. Thestrip is made of an… … [iOJ^a^-^v-^
Glass
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
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