This section is from the book "A Library Of Wonders And Curiosities Found In Nature And Art, Science And Literature", by I. Platt. Also available from Amazon: A library of wonders and curiosities.
This is a stone found in several places in Europe and Asia, and particularly in Sweden, Corsica, Cornwall, and the island of Anglesea in Wales. It is of a silky nature, very fine, and of a grayish colour, insipid, and indissoluble in water. It may be split into threads and filaments, from one to ten inches in length, it is indestructible by fire; whence it may be employed for many useful purposes. There are some sorts whose filaments are rigid and brittle, and others more flexible. The former cannot be spun into cloth, and the latter with difficulty. In consequence of its incombustibility, it was very much valued by the ancients for wrapping up the bodies of the dead. In the year 1702, an urn was discovered at Rome, with the bones of a human body wrapped in a cloth made of flexible asbestos. The method of preparing it is as follows: the stone is laid to soak in warm water, then opened and divided by the hands, that the earthy matter may be washed out. This earth is white like chalk, and makes the water thick and milky. This being several times repeated, the filaments are afterwards collected and dried: they are commodiously spun with flax. When the cloth is woven, it is best preserved by oil from breaking. It is then put into the fire; and the flax being burnt out, the cloth remains pure and white. It might also be made into paper; and, from its incombustibility, wills, or any other thing of importance, could be written on it. The Chinese make furnaces of this mineral, which are very portable.