Leaving this digression, however, it may be said that the peculiar properties of the mineral were known long before Charlemagne's time. The ancients, who believed it to be a plant, made a cere-cloth of it, in which they were accustomed to enwrap the bodies which were to be burned on the funeral pyre, so that the ashes might be retained, separate and intact, for preservation in the family urn, an aperture being left in the cloth to allow a free passage for the flames. How they succeeded in weaving this cloth is now unknown. It has been suggested that its accomplishment was effected by weaving the fibres along with those of flax, and then passing the whole through a furnace to burn out the flax.
The lamps used by the vestal virgins are also said to have been furnished with asbestos wicks, so that the modern adaptation of it to this purpose is only another exemplification of the truth of Solomon's saying that "there is nothing new under the sun."
The mineral has been variously described. In general terms it may be said to be a fibrous variety of serpentine, closely allied to the hornblende family of minerals, the Canadian variety of which is called by mineralogists "chrysotile." In the local vernacular of the mining districts this is "pierre-à-coton" (cotton-stone), perhaps as expressive a term as can be found.
The ore takes a variety of forms; much of it (especially that found in the States) is of a coarse woody character, of but little value for mercantile purposes.
Sir William Logan, in his "Geology of Canada," says that foliated and fibrous varieties of serpentine are common in veins of the ophiolites of the Silurian series, constituting the varieties which have been described under the various names of baltimorite, marmolite, picrolite, and chrysotile. The true asbestos, however, he says, is a fibrous variety of tremolite or hornblende.
In _Le Génie Civil_ for September, 1883, Canadian asbestos is thus described: "La chrysotile du Canada n'est pas comme l'amiante ordinaire formée d'un paquet de fils d'un blanc verdâtre et remplissant des cavités irrégulières: c'est une véritable pierre d'une densité comprise entre 2 et 3, qui se trouve en couches de 3 à 10 centimètres d'épaisseur. Cette pierre possède la propriété de se reduire en fibres perpendiculairement à sa longueur sous un effort très faible. Ses fibres transversales sont plus résistantes et beaucoup plus facile à filer, à tisser, et à feutrer que l'amiante ordinaire." This is as good a description of chrysotile as can be found anywhere.