I N D
Porcelain, gilding on---6$, 83
Gold coloured glazing for — — 627Glass changed into porcelain — 230experiments of the succession of thechanges — — — —■ — 233of the qualities and uses of the por-
of the effects of different cementing
materials-241
of the cementing of different forts of
glass--24;, 630
of the cause of the change-251
Printing-ink, process of preparing it 371,
- 374
Discharged-372
Purple dye, on linen and cotton — 434Powders of gold 75, 10;, 107, 108,no-176
Q,
ifiuartation, fee parting — —-148
ifiuickjilver, fee mercury
R.
Red dye on linen and cotton — — 434
Refining of gold, by cementation 90, 154
By aquafortis-— 90, 93, 147
By vitriolic acid — —--— 93
By aqua regia--— 96
By telling — — — —-144
with bismuth, &c.-14
By antimony-— — 136
Regal cement -470
Reverberatory furnace -— — 13
Rolling press ink-— 376
Rolls for flitting gold wire — — — 38Improved method of malting them 3 8,
— — — —--263
Ruby glass, fee glass
8.
Sal ammoniac, rough and sublimed, differin their power of volatilizing gold too
Sad microco/micus, how prepared from
E X.
Melted with platina 496
Gold precipitated by it-619
Vitrefied with gold-619
Salt, common, methods of purifying— 639Cause of its liquefying in the air —641
Prevented from deliquiating-642
Separation of its alcaline basis — 639Vitrification of earthen vessels promotedby its fumes--- — 464
Sands, black, as a colouring material—32;
Containing gold-188
Method of extracting gold from — 195
Sealing wax, black- 370
Seals, matter for making them from im-pressions in wax —-76
Sheep, composition for marking— — 379
Shell gold -—-— —- 63
Silk, Raw, method of cleansing-422
Loss of weight in cleansing—423,425Imperfections of the common method
-_- 423
obviated-— — 424
Method of dying black — — — 425Increase of weight from the black dye
---.-—423
Difference from woollen in receiving ablack d) e-— — 426, 427
Silver, tarnished to a golden hue—40,221
Mixtures of it with gold-— 83
As alloy for gold, loses its value — 119
Parted from gold-139, 147
Recovered from its solution — —150
Sulphurated —-161
Efflorescence in the cupel-260
Saturated solution not precipitated bycopper till more acid is added — 151'Polished, does not melt by a burning
glass-— --466
Melted with platina-522
Particular repugnance to platina — 524Glass tinged yellow by precipitates of it
— —-626
Substances stained black by its solution
-330,436
Solar light necessary for producing the
blackness-350
The colour destroyed by fife-439
destroyed by aquafortis, recovered by
fun --— -——-439
St%e,