Part 5 (1/1)

The process ofabout 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 ater and then treated with an aqueous solution of aain washed and then treated with a solution coht or ten parts of water mixed with an equal bulk of sulphate of alumina, which should be us pure as possible The htly 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 ater in an ordinary paper machine, and worked just like paper pulp

In order to manufacture a solid cardboard froainst 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 isallowed to flow over the cardboard A other uses, the asbestos paper has been recoh its applicability for this purpose is not so readily seen

Manufactured into paint, the de

It is used in the Houses of Parliae quantities at the several recent exhibitions at South Kensington

In the for equal to it as an efficient covering for boilers, steam pipes, hotblast furnaces, stills, &c For this purpose it is made of about the consistency of mortar and spread on with a trowel in the ordinary way Certain cheredients have to be added, which, while not injurious to the metal, cause the asbestos to adhere firmly to the plates, so that when dry it beco injured With a boiler carrying say 80 lbs steam pressure, the application of from 1- to 2 inches of this composition so well retains the heat in the boiler, that a thermometer with the bulb held close to the outer surface of the covering will not indicate more than 80 to 85 Fahrenheit Boilers, steam pipes, &c, covered in with this composition will, it is asserted by theof as much as 33 per cent in fuel[10]

This cement, which is made from a very cheap quality of asbestos, is now in common use in Canada and the States, where, as already shown, it is found to operate with a twofold effect, viz by lowering the teineers and fire the expenditure for fuel

It seee that its use in this country has as yet s recently erected in London, where engines are required to be in constant work for pueneral purposes, as well as for the dynareat a nuisance, and occasions so much loss in other ways, that very considerable expense is about to be incurred, with a view to lowering the te recently with an expert on this subject I asked whether the use of asbestos would not effect the desired object Yes, he answered, it would, but it is too expensive This certainly seee, as I know that the cement composition referred to is made of the very commonest quality of asbestos, of the refuse, in point of fact, which could probably be used for no other purpose The expense, therefore, cannot be great, and as to its mode of use, it is simply laid on with a trowel, like ularly effective I have stood in an engine-house where the boilers were covered with about two inches in thickness of this cement, which then showed a hard, dry, fir one's hand on the covering there was little entle warmth perceptible on the outside surface of the co atmosphere was scarcely, if at all, affected by the heat fros referred to on a previous page as being manufactured by a New York firm under contract with the United States Government, for use in some of their model war shi+ps, would no doubt be as effectual for the purpose, but naturally they would be ether different contrivance, and made so as to be easily removable when required, which, of course, is not the case with the so-called ceh the use of asbestos in this form does not see boilers and stealand as it already is on the other side, where its valuable qualities seem to be so s are now being manufactured in the States which in appearance exactly resemble cast-iron These have the additional valuable properties of extreth and a capability of ornamentation unobtainable with the usual cast-iron pipes mostly in use; paint in the case of the asbestos pipes not scaling off under heat as it will do in the case of ordinary iron pipes The manufacturers of these pipes claith of steel with the lightness of paper Tubes also are ineers which provide the for their wires both fire and waterproof, so as to preserve the perfect insulation of the wire

Asbestos rope is used for fire escapes and similar purposes, as well as for the trans and printing cloth it is frequently necessary to hang the fabric in loops from parallel rods for exposure to steam, air or ammonia In order that it should hold upon the rods, without straining or slipping, rope or strips of cloth are usually wound around the poles, but this does not reates, the difficulty, because the heat and corrosive action of the vapours will rot any covering; the first notice of the deterioration being generally the appearance of s the cloth which is in process of finishi+ng Asbestos rope and cloth are now largely manufactured and used for this purpose in the United States with very beneficial results

In co on the recent loss of life occasioned by the panic at the fire at the Exeter Theatre, a well-known journal, speaking of the variousfor escape, mentions the case of a o, and says that he would never go to bed in a strange house without having an apparatus of knotted rope affixed to a ring in the wall, by which he ency But, asks the journalist, what if the rope itself took fire? The answer naturally is, let it be an asbestos rope, then it will neither burn nor rot

The use of the fibre in the as stoves is too well known to need any remark

As a lubricant it is unrivalled

Another very i applied is in the manufacture of filters These are specially useful where the liquid to be filtered is of a caustic or strongly acid nature, or where the filter with residue is to be ignited without consu the filter, or where the residue is to be subsequently dissolved off the filter by acids or other solvents In many cases a very finely divided asbestos is desirable

This is accomplished by a process recently patented in Germany by Fr

Breyer, of Vienna The asbestos is first coarsely ground, and then ranular crystalline carbonate, which must be soluble in acids The carbonate should possess a hardness between 3 and 4, 5, according to the ether in a mill Afterwards the mass is treated with an acid until the carbonate has been dissolved out The escaping carbonic gas causes the asbestos fibres to be loosened and disintegrated from each other so as to render the hly washed ater before being used

Again, in the purification of foul gas, as well as for ventilating and deodorizing man-holes for cesspools, sewers, &c, its use is found to be unsurpassed by any other known material

Mr Boyd, in the paper so often referred to, says in regard to this, that he was some time previously asked to supply asbestos yarn spun in such a way as to have good capillary action, and, oninquiry, found it was to be used for the above purpose In describing theit, he says that there is placed over the opening rising froalvanized wire, interlaced with this asbestos yarn, the ends of the yarn dipping into a receptacle filled with liquid disinfectant, which, as they becoh the h are purified and rendered innocuous The systeas has been to cause it to rise through charcoal, but it is found that the ie of the gas, whereas in the arrangement just mentioned (which is that of Messrs Adaas rises freely, and is perfectly deodorized

There are, of course, very nuht be referred to or described, but probably those already ; and these, it is hoped, are at any rate sufficient to indicate the great value of this singular mineral product, as well as to confirm the statement hich I started, that this is indeed one of Nature's most marvellous productions

FOOTNOTES:

[10] There is a Patent Re now manufactured in New York which is said to be entirely formed of pure asbestos fibre, ths of the exact size of the pipes to be covered In this the asbestos fibres are so interlaced, that the sections, whilst possessing strength and flexibility, afford so large a nuhest non-conducting quality, whilst at the same time it cannot char or be in any way injured by the most intense heat fros for boilers and large surfaces are made in convenient forms in sheets, &c The same Company also manufacture what is called a Superator Jacket, both fire and waterproof, being in fact a flexible sheet of asbestos strengthened ire netting, the asbestos being waterproofed by a special process, and provided with patent lacings, so that the jacketsreadily re or loss of material