United States or Fiji ? Vote for the TOP Country of the Week !
This procedure is one which applies in general to the solution of fine mineral powders in acids. If a small residue remains undecomposed by the treatment of the silicate with acid, this may be filtered, washed, ignited and fused with sodium carbonate and a solution of the fused mass added to the original acid solution.
Oxide of load was added in some cases, not as a coloring matter, but as a flux, to facilitate the fusion of the glaze. In other cases the pigment used was covered with a vitreous coat of an alkaline silicate of alumina. The pigments were not applied to an entirely flat surface.
Thus feldspar consists of the insoluble silicate of alumina, together with certain alkaline silicates which are broken up by the action of water containing carbon dioxide, forming alkaline carbonates. These carbonates are freely soluble and contribute potash and soda to soils and river waters.
There is a layer of silicate cotton S C above the paste, and the mouth is sealed with black pitch P, through which a waste-tube W T allows the gas to escape. The Hellesen dry cell is like the "E. C. C.," but contains a hollow carbon, and is packed with sawdust in a millboard case.
The field was divided into three portions, and in April, 1843, was manured as follows: No. 1, with 90 lbs. of sulphate of magnesia, and 2 cwt. nitrate of soda to the statute acre; No. 2, with a compound from a manufacturer of chemical manures; No. 3, with 60 lbs. of silicate of soda and 2 cwt. of nitrate of soda to the acre; and, with the view of still further varying the experiment, a part of each portion was sowed with guano a fortnight after the application of the chemical manures.
To apply soluble glass for the preservation of buildings and monuments of porous materials, take a solution of silicate of potash of 35° Baume, dilute it with twice its weight of water, paint with a brush, or inject with a pump; give several coats.
Crossing from these shallower regions occupied by the ooze into deeper soundings, we find, universally, that the calcareous formation gradually passes into, and is finally replaced by, an extremely fine pure clay, which occupies, speaking generally, all depths below 2,500 fathoms, and consists almost entirely of a silicate of the red oxide of iron and alumina.
Sulphide of gold would have been produced by the action of sulphuretted hydrogen; hence probably our auriferous pyrites lodes, while silicate of gold might have resulted from a combination of gold chlorides with silicic acid, and thus the frequent presence of gold in quartz is accounted for.
If, as I hope will be the case, the silicate of soda should supply to peat its greatest deficiency, no one will more readily discover it than Mr. Baines. In the use of silicates of soda and potash, one precaution is very necessary, namely, that you really have a soluble silicate, not a mere mechanical mixture of ground flint and alkali.
The curiously smoked mutton-fat colour is one of the rarest, but to the amateur the more transparent and brilliant tints possess the greatest beauty. True jade, or nephrite, is a native silicate of calcium and magnesium, and does not exhibit either crystalline form or distinct cleavage.
Word Of The Day