Morton, Edward Reginald, 1867- · New York : E.B. Treat & Co. · leaf 67
ust be kept constantly moving. The wallsof the tube are thin and may be easily melted and.perforated by atmospheric pressure. Prolonged baking inan oven is also a very useful method, and seems to pro-duce a much more lasting effect than the heating by a.hot flame for a short period. Another method…
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