Five thousand receipts in all the useful and domestic arts / [Colin Mackenzie].

  • Colin Mackenzie
Date:
1823
Catalogue details

Licence: Public Domain Mark

Credit: Five thousand receipts in all the useful and domestic arts / [Colin Mackenzie]. Source: Wellcome Collection.

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    YO GIVE A DRYING QUALITY TO POPPY OTT, Into 3ibs. of pure water, put 1 0z. of sulphate | of zinc, (white vitriol) and mix the whole with 2 pounds of oi! of pinks, or poppyoil. Expose this mixture in an earthen vessel capable of standing the fire, toa degree of heat sufficient to maintain it ina slight state of ebullition. When one half or two-thirds of the water has evaporated, pour the whole into a large glass bottle or jar, and ‘leave it at rest till the oil becomes clear. Decant | the clearest part by means of a glass funnel, the | beak of which is stopped with a piece of cork: | when the separation of the oil from the water is | completely effected, remove the cork stopper, and supply its place by the fore-finger, which must be | applied in such a manner as to suffer the water to escape, and to retain only the oil. - Poppy-oil when prepared in this manner be- | comes, after some weeks, exccedingly limpid and ) colourless, TO GIVE A DRYING QUALITY TO FAT OILS. ‘Take of nut-oil, or linseed-oil, 8 Ibs. white lead, slightly calcined, calcined, vitreous oxide of lead, (litharge) 12 oz. a head of garlic, or a small onion. | When the dry substances are pulverized, mix them with the garlic and oil, over a fire capable of maintaining the oil in a slight state of ebulli- tion : continue it till the oil ceases to throw up | scum, tillis assumes a reddish colour, and till the | head of garlic becomes brown. A pellicle will | then be soon formed on the oil, which indicates that the operation is completed. Take the vessel from the fire, and the pellicle, being precipitated by rest, will carry with it all the unctuons parts which rendered the oil fat. When the oil becomes clear, separate it from tie deposit, and put it ‘into wide-monthed bottles, where it will coin- pletely clarify itself in time, and improve in qua- lity. Another Method. Take of vitreous oxide of lead, (litharge) 14 oz. sulphate of zinc, (white vitriol) g of an oz. Or 3 gros. linseed, or nut-oi], 16 oz. The operation must be conducted as in the pre- ceding case. The choice of the oil is not a matter of indif- ference. Ifit be destined for painting articics exposed to the impression of the external air, or for delicate painting, nut-oil or poppy-oil will be requisite. WLinseed-oil is used for coarse paint- fing, and that sheltered from the effects of the ;rain and of the sun. A little negligence in the management of the ‘fire, has often an influence on the colour of the oil, to which a drying quality is communicated ; in this case it is net proper for delicate painting. This inconvenience may be avoided by tying up the drying matters in a small bag; but the dose of the litharge must then be doubled. The beg must be suspended by a piece of packthread fastened to a stick, which is made to rest on the edge of the vessel in such a manner as to .kecp the bag at the distance of an inch from tit bot- tom of the vessel. A pellicle will be formed as in the first operation, but it will be slower in making its appearance. Another. A drying quality may be communicated to cil
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