Ochre. Is a kind of yellow or red earth, used by painters. It is an oxide of iron, Under which head it has been described.
Spanish Brown. Is an iron ore. dug out of the ground. Among painters it is used as the first and priming colour. It works well if ground fine. In choosing good, that which is freest from stones, and of the deepest hue, is the most esteemed. For many purposes it requires to be burnt.
Ruddle, Bed Hematites, Or Bloodstone. Is a sort of dusky red chalk, or earth, found in several parts of England, chiefly in iron mines. It was called by the ancients haematites. Pliny reckons five kinds. That commonly used by painters is factitious, being made of Armenian bole, and other drugs. The native or fossil kind comes from Egypt, Bohemia, etc. The gilders use it for burnishers to polish their gold with.
Black. Something opaque and porous that imbibes all the light falling thereon, reflects none, and therefore exhibits no colour. There are various kinds of blacks. The dyers when they are to dye cloths, etc, black, first dye it blue, with woad and indigo, and the black is given afterwards with logwood, or galls, copperas, and sumac.
There is what is called Jesuit's black, which dyes black without first dyeing blue. It is said to have been invented by the Jesuits, and was practised in their houses. There is a German black made with ivory and burnt peach stones, mixed and ground with burnt lees of wine.
Ivory Black. Is made of ivory burnt between two crucibles well luted ; which being thus rendered perfectly black, is ground in water, and made into little cakes. A crucible is a chemical vessel made of very different materials, as clays, plumbago, platina, or manganese, and so tempered and baked as to endure the greatest fire.
Lamp-Black. Is the sooty fumes of rosin, prepared by melting and purifying the rosin in iron vessels, then setting fire to it under a chimney, or other place, lined with sheep skins, or thick linen cloth to receive the vapour or smoke, which is the black. It is
Sometimes prepared from the resinous parts of woods, burnt under a kind of tent which receives it. Of this kind we hare much from Sweden and Norway. This black takes tire very readily.
Spanish Black. Is so called, because first invented by the Spaniards, and most of it brought from Spain. It is no other than burnt cork, and used in various works, particularly among painters.
There are several colours that require burning, as first, Lamp-Black, which is of so greasy a nature, that, except it be burnt, it will require a long time to dry. The method of burning, or rather drying, lampblack, is as follows . - Put it into a crucible, over a clear tire, letting it remain until it be red hot, or so near it that there is no manner of smoke arising from it.Secondly, Umber, which, if it be intended to be a shadow for gold, etc., then burning suits. In order to burn umber, you must put it into the naked fire in large lumps, and not take it out till it be thoroughly red hot; or, if you wish to be more curious, put it into a crucible, and make it red hot. Umber, or martial clay, consists principally of particles of decayed wood mixed with bitumen.
Ivory also must be burnt to make black, thus, fill two crucibles with shavings of ivory, then clap their two mouths together, and bind them fast with an iron wire, and lute the joints close with clay, salt, and horse-dung, well beaten together; then set it over the fire, covering it all over with coals; let it remain on the fire, till you are sure that the matter enclosed is thoroughly red hot; then take it out of the fire, but do not open the crucibles till they are perfectly cold ; for, were they opened while hot, the matter would turn to ashes, and so it will if the joints are not luted close.
Bister, Or Bistre. Is made of chimney soot boiled, and afterwards diluted with water; serving painters to wash then-designs.
Black Chalk. Is used for designing, and is esteemed preferable to black lead. It is nothing more than argillaceous slate, cut into long slips, fit to be held in the portcrayon. There are two kinds, the one French, and the other Italian; the former is 6oft, and the latter hard.