Hartley has employed it with great success, and in cyanite (a silicate of aluminium) has found a material which is infusible at the temperature of this flame, and is therefore suitable to hold the substance which it is desired to examine.
Cylinders, tanks and independent boilers should be encased in a non-conducting material such as silicate cotton, thick felt or asbestos composition.
Minerals, like glauconite, which contain ferrous silicate, may in like manner yield limonite, on weathering.
Aluminium silicate is the chemical body of which all clays are nominally composed.
It may be skimmed off the underlye and placed direct in the frames for solidification; but that is a practice scarcely at all followed, the addition of resin soap in the pan and the subsequent " crutching in " of silicate of soda and adulterant mixings being features common to the manufacture.
A further means of enabling a soap to contain large proportions of water and yet present a firm consistence is found in the use of silicate of soda.
ULTRAMARINE, a blue pigment, consisting essentially of a double silicate of aluminium and sodium with some sulphides or sulphates, and occurring in nature as a proximate component of lapis lazuli.
It has been suggested that ultramarine is a compound of a sodium aluminium silicate and sodium sulphide.
Artificially formed crystals of the various species of mica have been observed in furnace-slags and in silicate fusions.
The alum schists employed in the manufacture of alum are mixtures of iron pyrites, aluminium silicate and various bituminous substances, and are found in upper Bavaria, Bohemia, Belgium and Scotland.
- Sheet-glass is almost wholly a soda-lime-silicate glass, containing only small quantities of iron, alumina and other impurities.
The fire may well have caused the natron, an impure form of carbonate of soda, to combine with the surrounding sand to form silicate of soda, which, although not a permanent glass, is sufficiently glass-like to suggest the x11.4 FIG.
66) actually records the discovery which effected the conversion of deliquescent silicate of soda into permanent glass.
It is only soluble in a mixture of hydrofluoric and nitric acid, or in solutions of the caustic alkalis, in the latter case yielding hydrogen and a silicate: Si-}-2KHO+H 2 O = K 2 SiO 3 +2H 2.
The term clay is often used by chemists to denote hydrated silicate of alumina (Al 2 O 3 2SiO 2.2H 2 O), of which kaolin or china clay is a fairly pure form.
In diameter) of sand and other minerals derived from the decomposition of rocks, with a small amount of silicate of alumina.
Of less importance is the silicate, Zn 2 SiO 4 H 2 0, named electric calamine or hemimorphite; this occurs in quantity in Altenburg near Aix-laChapelle, Sardinia, Spain and the United States (New Jersey, Pennsylvania, Missouri, Wisconsin).
Oxide of zinc, like most heavy metallic oxides, is easily reduced to the metallic state by heating it to redness with charcoal; pure red zinc ore may be treated directly; and the same might be done with pure calamine of any kind, because the carbon dioxide of the zinc carbonate goes off below redness and the silica of zinc silicate only retards, but does not prevent, the reducing action of the charcoal.
Here very clean non-magnetic concentrate of willemite, which is an anhydrous zinc silicate and a very highgrade zinc ore, is separated from an intimate mixture of willemite, zincite and franklinites, with calcite and some manganese silicates.
Calcium silicate is also present in the minerals: olivine, pyroxenes, amphiboles, epidote, felspars, zeolites, scapolites (qq.v.).
As silicate of soda) and in other soda-containing rocks.
It is a silicate, containing aluminium, magnesium and iron' brought originally from Greenland, and since found in a rock from the Vizagapatam district in India.
The slag, in order that it may have such an excess of base that this will retain the phosphoric acid as fast as it is formed by the oxidation of the phosphorus of the pig iron, and prevent it from being re-deoxidized and re-absorbed by the iron, should, according to von Ehrenwerth's rule which is generally followed, contain enough lime to form approximately a tetra-calcic silicate, 4CaO,S10 2 with the silica which results from the oxidation of the silicon of the pig iron and tri-calcic phosphate, 3CaO,P205, with the phosphoric acid which forms. The danger of this " rephosphorization " is greatest at the end of the blow, when the recarburizing additions are made.
Where the carbon, in thus diffusing inwards, meets particles of the slag, a basic ferrous silicate which is always present in wrought iron, it forms carbonic oxide, FeO+ C = Fe+CO, which puffs the pliant metal up and forms blisters.
In France this slaking is conducted systematically by the makers, the freshly burned lime being sprinkled with water and stored in large bins where slaking proceeds slowly and regularly until the whole of the surplus uncom bined lime is slaked and rendered harmless, while the cementitious compounds, notably tricalcium silicate, remain untouched.
For lager-beer cellars and fermenting rooms, for bacon-curing cellars, and for similar purposes, brick walls with single or double air spaces are used, and sometimes a space filled with silicate cotton or other insulating material.
The silicate in the form of a concentrated solution is crutched or stirred into the soap in a mechanical mixing machine after the completion of the saponification, and it appears to enter into a distinct chemical combination with the soap. While silicate soaps bear heavy watering, the soluble silicate itself is a powerful detergent, and it possesses certain advantages when used with hard waters.
Hopkinson, working at Chance's glass works, subsequently made an attempt to produce a titanium silicate glass, but nothing further resulted.
Any silicate present is also converted into bicarbonate with elimination of silica, which must be filtered off.
Magnesium is found widely distributed in nature, chiefly in the forms of silicate, carbonate and chloride, and occurring in the minerals olivine, hornblende, talc, asbestos, meerschaum, augite, dolomite, magnesite, carnallite, kieserite and kainite.
Some, such as victoria stone, imperial stone and others, are hardened and rendered non-porous after manufacture by immersion in a solution of silicate of soda.
This insulation generally consists of materials such as charcoal, silicate cotton, granulated cork, small pumice, hair-felt, sawdust, &c., held between layers of wood or brick, and forming a more or less heat-tight box.
Granulated cork has practically the same insulating properties as silicate cotton, and the same thicknesses may be used.
Of good silicate cotton.
Of silicate cotton.
In Australia and New Zealand pumice, which is found in enormous quantities in the latter country, takes the place of charcoal and silicate cotton.
The mineral name "smithsonite" was originally given in his honour by Beudant to zinc carbonate, but having also been applied to the silicate, the name is now rarely used.
At the temperature of the furnace the silica (sand) attacks the calcium phosphate, forming silicate, and setting free phosphorus pentoxide, which is attacked by the carbon, forming phosphorus and carbon monoxide.
The calcium silicate remains in the furnace in the form of a liquid slag, which may be run off, so that the action is practically continuous.
Kaolin may with advantage be used in addition to or in part substitution for sand, because the double silicate thus formed is more fusible than the single silicate of lime.
The chief deposits consist of red oxide, silicate and franklinite, and the average zinc content is 23%.
The crystals belong to the monoclinic system, and it is a curious fact that in habit and angles they closely resemble pyroxene (a silicate of calcium, magnesium and iron).