INDEX.

Size, gold, for gflding— —-62

for varnishes-369

Smoke and fumes in furnaces, made to pass

down through the grate-79

Dome for carrying them off — — 33

Soda, fait, whence obtained-596

The fame with the basis of sea fait 596

Solar light, differences from common firein producing colours from metallic

solutions ——--150,98

in the combustion of black bodies 318

Solder, for gold-82, 617

for iron —-—-82

Soot, its difference from charcoal as a pig-ment -357, 376

Difference of different foots-339

depend more on the manner of burn-ing than on the subject 342, 343Tinctures in diffefent menstrua — 339Brown pigment prepared from — 340

Specula, metals proposed for-86, 576

Spirit of wine, its use in cleaning gold-

iaces, &c.-39

Separates gold from acids-103

Gold separated by it from platina 485Method of dephlegmating for varnishes,&c.-224, 625

Steel instrumentt, way of tempering equal-ly a number of small ones all at once 32

Stones, stained purple-97

stained black-— 436

Method of drawing designs with the

colouring liquids — —--439

Artificial colours distinguished from na-

Stove, for warming a room with little fuel-13

Sublimate corrosive, its action on metals

-471

Its use in purifying gold — — 70, 94

Sulphurated a kali, its effects on gold 111,—-—-11 z

on platina—-— — — —499

T.

•Talc, gold coloured, contains no gold 190

Its use for making gold coloured span-gles in glass-223

Taming, oak saw dust substituted to oakTar , composition of it for preserving wood,

&C.-362

Tests, method osmaking-,45

From mineral stones-144.

Testing ofgolu and silver, process of —146

Thermometers, made with different fluids,not comparable from twofixt points2 57A mercurial and spirit one made to cor-respond -256

Not influenced by difference in the glass

- 2 j5

Thread, common method of dying black

-429

Proposal for a more durable black 433

Tiles, painted black in imitation of black

glazed ones-362

Tin, Its effects on gold-— 8;

Gold coated with it by boiling in tinvessel with alcali-39

Precipitation of gold by its solution 1 to,

— — — —-,y5

Produces a gold colour with copper 624Melted with platina in different pro-portions -510

Calcined, &c. with gold-89,617

with platina-— 557

Touch-needles, manner of preparing them-119

Touchstone, for metals-121

Directions for its use--1 zz

Its requisite qualities-- 121, 123

Of what genus of stones-620

Toxiccdendra, juices from them which stainlinen of durable black-330, 331

Trees, conjecture on the cause of some re-sisting, and others being burst, by strongfrosts —-- — — 258

V.

Varnishes, Amber--367, 614

Black, for japanning, Le.-- 366

hard, for papier mache-366

Q_q q q Varnijhes,