The Chevalier Aldini's idea, previously mentioned, has been recently revived in Paris, the firemen there having been furnished with asbestos clothes. Immediately after this was done it was reported in the papers that on a conflagration occurring in the basement of a building there, the firemen arrived, clad in their asbestos suits, and were thereby enabled to descend at once into the basement, where they extinguished the fire in a very short time, and so prevented what might have been a great calamity. And according to the papers it appears that the same course is now about to be taken in England, and the London firemen at any rate protected in a similar manner; and there can be little doubt that this course will presently be universally adopted for the protection of the men engaged in saving life and property from destruction by fire. Nothing has yet been discovered that will equal asbestos for this purpose. It will neither burn nor smoulder, and is as impervious to fire as well made mackintosh is to water.
Manufactured into cloth and paper, it is in use in sugar refineries, chemical laboratories, &c., for straining and other purposes, especially for filtering acids and similar fluids. A coarser kind of cloth is used for stokers and furnacemen's aprons, for salvage blankets, and gloves. A special quality of glove made of asbestos cloth, lined with rubber, is supplied for electric light work.
A further development of the industry is indicated by the announcement that a New York manufacturing firm has recently taken over a large contract for the manufacture of mail bags out of asbestos cloth.
It is also proposed to be used as an inner sole or lining for boots and shoes with the object of keeping the feet warm in winter and cool in summer, the material possessing the double advantage of being at once a preserver of heat and a protector from cold.
For cold storage buildings it will doubtless be found invaluable. There are buildings in New York, principally for fish preservation, which are built with double walls surrounding the cold chambers, having some kind of non-conducting material between the walls by way of lining. For this purpose asbestos would be unsurpassed, and the cheap No. 3 quality would answer perfectly well.
Mr. Boyd, in the lecture before referred to, says that some years ago, when resident at Genoa, he was one of the members of a committee for procuring a new floating chapel for the use of seamen. The old chapel was built on the deck of a hulk, but the extremely high summer temperature caused the repairs to be both frequent and costly. The committee therefore wanted the new chapel to be built of iron, but were deterred by the fear that its roof and sides, exposed to the sun, would get so hot as to render the interior unbearable. He therefore proposed to fill up the space between the outer skin and the inner boarding with asbestos ground to a rough powder; and this suggestion was adopted, the powder being tightly rammed in by the carpenters. The result, he informs us, was so successful that whilst the outside temperature stood at 100°, the temperature inside, when doors and windows were kept shut, did not exceed 70°. And he therefore suggests that asbestos powder might be used in a similar way for rendering the deck cabins of steamers navigating the Red Sea and Suez Canal more comfortable for the passengers.
For wall and ornamental papers it is being largely used, and a superior quality of asbestos writing paper is now being made in Paris. One can easily imagine a great future in this line for asbestos paper written or printed on with asbestos ink for all kinds of registers and permanent records, bankers' and merchants' books, and the like. One of the leading manufacturers in New York already prints his price lists on asbestos paper. And another has on show fine papers as susceptible of receiving good impressions from type as any in use in modern books. Coloured wall papers also are manufactured in great variety, which are not merely incombustible, but practically indestructible by fire; and which retain, even after severe heat tests, their colourings, markings and letterings as clearly impressed and as vividly visible as before. Boards also are made of asbestos, varying from the thinnest and lightest card to heavy shelving, fit either for partitions in safes or for use in large libraries.
In a recent number of "L'Industrie Moderne" I found an account of a new process invented by a Mr. Ladewig for manufacturing pulp and paper from asbestos fibre, which he asserts will not only resist the action of both fire and water, but will absorb no moisture; this pulp, he says, may be used as a stuffing and for the joints of engines. He further proposes to use it in the form of a solid cardboard as a roofing material for light structures.
The process of manufacture consists in mixing about 25 per cent. of asbestos fibre with about 25 or 35 per cent. of powdered sulphate of alumina. This mixture is moistened with an aqueous solution of chloride of zinc. The mixture is washed with water and then treated with an aqueous solution of ammoniacal gas. The mixture is again washed and then treated with a solution composed of one part of resin soap and eight or ten parts of water mixed with an equal bulk of sulphate of alumina, which should be us pure as possible. The mixture thus obtained should have a slightly pulpy consistency. Finally, there is added to it 35 per cent. of powdered asbestos and 5 to 8 per cent. of white barytes. This pulp is treated with water in an ordinary paper machine, and worked just like paper pulp.
In order to manufacture a solid cardboard from asbestos which shall be proof against fire and water and capable of serving as a roofing material, sheets of common cardboard, tarred or otherwise prepared, are covered with the pulp. The application is made in a paper machine, the pulp being allowed to flow over the cardboard. Among other uses, the asbestos paper has been recommended for the manufacture of cigarettes, though its applicability for this purpose is not so readily seen.