Brunner found that 300 parts of quicksilver, 114 of sulphur, 75 of caustic potassa, and from 400 to 450 of water, form very suitable proportions for the moist process; that the best temperature was 113° F.; and that 122° was the highest limit of heat compatible with the production of a fine colour.
The theory of this process is by no means clear. We may suppose that a sulphuret of potassium and mercury is first formed, which is eventually destroyed, in proportion as the oxygen of the air acts upon the sulphuret of potassium itself. There may also be produced some hyposulphite of mercury, which, under the same influence, would be transformed into sulphuret of mercury and sulphate of potash.
Sulphuret of potassium and mercury furnish also vermillion, but it is not beautiful. Red oxide of mercury, calomel, turbith mineral, and the soluble mercury of Hahnemann, treated with the sulphuret of potassium, or the hydrosulphuret of ammonia, are all capable of giving birth to vermillion by the humid way.
The vermillion of commerce is often adulterated with red lead, brickdust, dragon’s blood, and realgar. The first two, not being volatile, remain when the vermillion is heated to its subliming point; the third gives a red tincture to alcohol; the fourth exhales its peculiar garlic smell with heat; and when calcined in a crucible with carbonate of soda, and nitre in excess, affords arsenic acid, which may be detected by the usual chemical tests.
VINEGAR MANUFACTORY, BY MALT. Annual produce, 100,000 gallons.
| Expenses for One Month. | £ | s. | d. | |||
|---|---|---|---|---|---|---|
| Cost of material and fuel for 8,333 gallons, at 83⁄4d. | 303 | 16 | 2 | |||
| Wages to 8 workmen, at 25s. per week | 40 | 0 | 0 | |||
| Salaries to clerks, manager, and traveller | 83 | 6 | 8 | |||
| Travelling expenses | 30 | 0 | 0 | |||
| Three horses’ keep | 7 | 10 | 0 | |||
| Rent and taxes | 25 | 0 | 0 | |||
| £489 | 12 | 10 | ||||
| Expenses for 5 months, at 489l. 12s. 10d. | 2448 | 4 | 2 | |||
| Duty on 41,665 gallons, at 2d. | 347 | 4 | 2 | |||
| Stock of utensils | 1500 | 0 | 0 | |||
| £4295 | 8 | 4 | ||||
| Produce of 100,000 gallons, at 1s. 8d. | £8333 | 6 | 8 | |||
| Expenses for 12 months, at 489l. 12s. 10d. | £5875 | 18 | 0 | |||
| Duty on 100,000 gallons, at 2d. | 833 | 6 | 8 | |||
| Interest on capital, 4295l. 8s. 4d. | 214 | 4 | 5 | |||
| 6923 | 9 | 1 | ||||
| Net profit | £1409 | 17 | 7 | |||
| See [Acetic Acid]. | ||||||
VIOLET DYE, is produced by a mixture of red and blue colouring-matters, which are applied in succession. Silk is dyed a fugitive violet with either archil or brazil wood; but a fine fast violet, first by a crimson with cochineal, without tartar or tin mordant, and after washing, it is dipped in the indigo vat. A finish is sometimes given with archil. A violet is also given to silk, by passing it through a solution of verdigris, then through a bath of logwood, and, lastly, through alum water. A more beautiful violet may be communicated by passing the alumed silk through a bath of brazil wood, and after washing it in the river, through a bath of archil.
To produce violets on printed calicoes, a dilute acetate of iron is the mordant, and the dye is madder. The mordanted goods should be well dunged.
A good process for dyeing cottons violet, is—first, to gall, with 18 or 20 pounds of nut-galls for every 100 pounds of cotton; second, to pass the stuff; still hot, through a mordant composed of—alum, 10 pounds; iron-liquor, at 11⁄2° B., and sulphate of copper, each 5 or 6 pounds; water, from 24 to 28 gallons; working it well, with alternate steeping, squeezing, airing, dipping, squeezing, and washing; third, to madder, with its own weight of the root; and fourth, to brighten with soap. If soda be used at the end, instead of soap, the colour called prune de monsieur will be produced; and by varying the doses of the ingredients, a variety of violet tints may be given.
The best violets are produced by dyeing yarn or cloth which has been prepared with oil as for the Turkey-red process. See [Madder].