National Geographic : 1943 Jan
From Sand to Seer and Servant of Man @ National Geographic Society Kodachrome by Willard It. Culver Cocoon of Silklike Glass Fiber Is a Marble Which Yields 98 Miles of Filament Carloads of these flexible fibers are banded into retainer mats for storage batteries. Tons of yarn go into insulation for wires, cables, generators, and other electrical equipment. Weaving of glass tablecloths, neckties, draperies, and shower curtains is halted for the duration.