Valuable Secrets concerning Arts and Trades:
or Approved Directions, from the best Artists, for the Various Methods...
Printed by Thomas Hubbard,
Norwich, 1795Chap. V. Secrets concerning colours & painting.
§ VIII. Preparations of colours of all sorts for oil, water, and crayons.
XCI. A good azure.
Take two ounces of quicksilver; sulphur and ammoniac salt, of each one ounce. Grind all together, and put it to digest in a matrass over a slow heat. Increase the fire a little; and, when you see an azured fume arising, take the matrass off from the fire. When cool, you will find in the matrass as beautiful an azure as the very ultramarine itself.
XCII. An azure from silver, done in less than a fortnight.
Dissolve in very strong vinegar, as much gem-salt and roch-alum, as it will be able to dissolve. Put this in a new pipkin; and, over it, hang up laminas of the finest tested silver. Cover the pot, and lute it well. Bury it in the cellar; and ten or fifteen days afterwards take off the azure, which you will find about the laminas. Replace things as before; and, ten days afterwards, the same again; and repeat this process as many times as you can get any azure by it.
The silver laminas may steep in the vinegar if you think proper.
Besides gem-salt, and roch-alum, some likewise dissolve alkali in the vinegar.
XCIII. To make an azured wafer.
1. Gather wallwort's grains between green and ripe, and bake or stew them in a pan. When they have boiled a considerable time, strain them through a cloth, and keep the juice in a glass phial; its colour will never change, and will keep for ever very fine.
2. Have next dog's dung very dry. Pulverise it very fine, and sift it through a silk sieve. Then grind it on a marble with the wallwort's juice and a mullar, as painters do their colours, and you will find this paste of a very fine azure colour.
3. Now, if you tinge any water with this, by putting it in a phial to soak, you may dye whatever you will with it, such as thread, cotton, cloth, &c.
XCIV. Another way of making azure.
Take the bulk of a filbert of ammoniac salt, which you dissolve in a common half-pint glass tumbler of water. Then pound and fire, all together, one ounce of vitriol, and one and a-half of quick lime. Put this powder into the water in which the ammoniac salt was dissolved. Leave this to infuse for the space of forty-sight hours, and at the end of that lerm the azure mall be done.
XCV. A fine azure.
Make an incorporation of three ounces of verdigrise, and of an equal quantity of ammoniac salt which you dilute with a little tartar-water, so as to raake a thick paste of it. Put this composition into a glass, and let it rest for a few days, and you will have a fine azure.
XCVI. Another way.
Pulverise and mix well together one part of ammoniac salt, and two of verdigrise, with a little ceruse. Then pour over it oil of tartar enough to make a clear paitfc of it. Put this in a glass vessel, which take care, to stop and lute well. When done, put it in an oven along with the bread, and take it out with it also, then the az.ure will be done.
XCVII. Another way.
Take sublimed mercury, four parts; ammoniac salt, two; sulphur-vivum one. Pulverise the whole, and put the powder in a matrass, which; lute well with the lute of sapience. Put this matrass on a mild and slow fire; and, when you see a white fume beginning to rise, stop the fire. When the matrass is cold, break it, and you will find a very fine azure at the bottom. Now take it and work it with lukewarm water first, and then with cold.
Note. There are some who absurdly warn it with lye, or a drone: limewater; but they most undoubtedly spoil their azure entirely. What is most advisable, and indeed the only preparation allowable, is to boil a little white honey in tha water, and skim it; and when that water becomes lukewarm, wash the azure with it. This last may contribute to give it a fine colour, but the other will certainly hurt it.
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