FIRE-DEFYING FABRIC

Sun (Auckland), Volume II, Issue 559, 11 January 1929, Page 13

FIRE-DEFYING FABRIC

ROCK WOVEN LIKE WOOL Few of the world's minerals have had a more curious history than asbestos, and few are more curious in themselves. Though commercially merely 50 years old, it was known to the ancients. The Greeks called it “the unconsumable,” while the Tartars and Assyrians were aware of the strange, fibre-like rock that could nevertheless be woven like wool and could withstand fire. Its earliest known use was for the shrouds of kings, whose dead bodies were wrapped in asbestos cloth, so that their ashes might be kept separate from those of the funeral pyre. It is said that Charlemagne possessed a tablecloth of asbestos, and when a feast was over, he took pride in amazing his guests by ordering the cloth to be thrown into the fire—to bleach it! Asbestos is a rock as heavy and dense as marble, yet it can be broken into brittle and pliable fibres that are light enough to float on water. For commercial use, the rock is transformed into felt or paper, woven into heavy cloth, pressed into blocks for brake linings and the like, “or spun into thread so fine that 100 yards of it weigh less than an ounce! Asbestos is extensively used in ihe manufacture of safety-curtains for theatres, while it also makes excellent moulds for castings. It is also one of the finest insulators, not only for heaf. but for electricity. It is easily machined, does not warp, resists almost all acids, and is a positive nonconductor at almost any temperature.