The Uses of Asbestos — A Wonderful Substance

1896

Being Incombustible, It Is a Valuable Compound in Many Industries

Asbestos is a wonderful substance. The name comes from a Greek word meaning inconsumable. Fire will not burn it, acids will not gnaw it, weather will not corrode it.

It is the paradox of minerals, for it is quarried just like marble. The fibers of which it is composed are soft as silk and fine and feathery enough to float on water. Yet in the mines they are so compressed that they are hard and crystalline like stone.

Although the substance has been known for ages in the form of mountain cork or mountain leather, comparatively little has been learned as to its geological history and formation. A legend tells how the Emperor Charlemagne, being possessed of a tablecloth woven of asbestos, was accustomed to astonish his guests by gathering it up after the meal, casting it into the fire, and withdrawing it later, cleansed, but unconsumed.

Yet, although the marvelous attributes of asbestos have been known for so long, they were turned to little practical use until about twenty years ago. Since that time the manufacture of the material has grown until it can take its place with any of the industries of this country. Indeed, so rapid has been its progress and development that there is almost no literature of any kind on the subject, and, to the popular mind, it is still one of those inexplicable things.

Up to the late '70's nearly all the asbestos used to come from the Italian Alps and from Syria, but one day explorers discovered a rich deposit in the eastern township of Quebec. Companies were formed, and, in 1879, the mines were opened. Remarkable as it may seem, however, although the Canadians started factories, in the operation of which they were substantially backed by English capital, it was an American concern, with headquarters in New York, that developed the industry most rapidly. The company has now grown so large that it has branches in nearly all of the large cities of the country and the machinery used is specially made and peculiarly adapted to the manufacture of asbestos articles. There are also a large number of factories in England.

The veins of chrysotile, as the Canadian asbestos is called, are from two to four inches in thickness, and are separated by thin layers of hornblende crystals. The nearer to the surface the vein runs, the coarser are the fibers and the less valuable. The mining is done by the most improved machinery. Holes are drilled in long rows into the sides of the cliffs by means of steam drills. They are then loaded with dynamite and exploded simultaneously in such a way that a whole ledge of the rock falls at once. Then the workmen break out as much the pure asbestos as possible, load it into tubs or trucks, which are hoisted out and run along to the "cobhouse." Here scores of boys are kept busily employed crumbling or "cobbling" the pieces of rock away from the asbestos and throwing the good fiber to one side, where it is placed in sacks for shipment to the factory.

The greatest work in connection with the mining of asbestos is in disposing of the waste rock and the refuse of the quarry. Only about one-twenty-fifth of the material quarried is real asbestos, and the rocky parts have to be carried to the dumps at great expense.

As the asbestos comes from the mine it is of a greenish hue, and the edges are furred with loose fibers. The more nearly white asbestos the better its grade. The length of fiber is also of great importance, the longest being the most valuable. From the mines the asbestos is taken to the manufactories in the United States. — Engineer.