Fig. 5.—Polishing with Wooden Wheel. turn fades out, and on removal from the mold is carriedto the lehr for annealing. This is a tunnel averaging from 100 to 150 feetlong, of varying temperature throughout its entirelength, the end at which the glass enters being cool.The glass is made to move at a… … Fig, 6.—Washing oil Pumice. 39 enough to turn the glass red again, but not enoughto melt it. From thence on the heat gradually de-creases, until at the far end the glass comes out cold. This is a very important process, as a lack ofproper annealing will cause the glass to fly, orcrack, or go to…
Pottery · Glass · Glassware
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