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A dictionary of arts, manufactures, and mines : containing a clear exposition of their principles and practice / by Andrew Ure
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73.

IVORY BLACK.

5. Med dyemay be given by imbuing the ivory first with the tin mordant, th cplunging it in a bath of Brazil wood, cochineal, or a mixture of the two. Lac-dye

be used with still more advantage, to produce a scarlet tint. If the scarlet ivory b eplunged for a little in a solution of potash, it will become cherry red. ,

6. Violet dyeis given in the logwood bath to ivory previously mordanted for a shottime with solution of tin. When the bath becomes exhausted, it imparts a lilach h u ^Violet ivory is changed to purple-red by steeping it a little while in water containingfew drops of nitro-muriatic acid.

Witli regard to dyeing ivory, it may in general be observed, that the colors penel't*better before the surface is polished than afterwards. Should any dark spots appear, mmaybe cleared up by rubbing them with chalk; after which the ivory should be7once more to produce perfect uniformity of shade. On taking it out of the boilin? n j-dye bath, it ought to be immediately plunged into cold water, to prevent the chancefissures being caused by the heat. a

If the borings and chips of the ivory-turner, called ivory dust, be boiled in watei;kind of fine size is obtained. .

The importation of elephants teeth for home consumption was, in 1834, 4,282 cWin 1835, 3,698; and in 1836, 4,584 cvvts.; duty, 1 1. per cwt. ,

IVORY BLACK (Noir divoire, Fr.; Kohle von Elfeubein, Germ.) is prepared * rivory dust, by calcination, in the very same way as is described under 'Bonk Black-The calcined matter, being ground and levigated on a porphyry slab, affords a betiful velvety black, much used in copperplate printing. Ivory black may h epared upon the small scale, by a well regulated ignition of the ivory dust in a covcrucible.

K.

the 5 ea '

JvALI. The Arabs gave this name to an annual plant which grows near c tedshore ; now known under the name of salsola soda , and from whose ashes they ex* g er .a substance, which they called alkali, for making soap. The term kali is used olirman chemists to denote caustic potash; and kalimn, its metallic basis ; inst ea,° flS /ier,potassa and -potassium , of preposterous pedigree, being derived from the words l J0tthat is, ashes prepared in a pot. , jhe

KAOLIN (Terre a, porcelaine, Fr.; Porzellanerde , Germ.) is the name 5*® [gins-Chinese to the fine white clay with which they fabricate the biscuit of then P° rcSee Clay. Berthiers analyses of two porcelain earths are as follows :

Analyses.

From Passau .

From Saint Tries-

Silica ....

45-06

46-8

Alumina . . .

32-00

37-3

Lime ....

0-74

-

Oxyde of iron

0-90

Potass ....

_

2-5

Water

18-0

13-0 _

96-7

9£d>^___

KARABE', a name of amber, of Arabic origin, in use upon the Continen ; n cin e .''

KELP (Varec, Fr.; Wareck, Germ.) is the crude alkaline matter produce ^ r0 ck s *ating various species of fuci, or sea-weed. They are cut with sickles from ^ j fiathe summer season, dried and then burned, with much stirring of the pas J . j()0 re-analyzed many specimens of kelp, and found the quantity of soluble mat® soluble c °of the best to be from 53 to 62, while the insoluble was from 47 to 38.sisted of

Sulphate of Soda -

. 8-0

19-0

5-5

Soda in carbonate and sulphuret -

. 8-5

37-5

Muriate of soda and potash

_

. 36-5

53-0

62-0