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142。 SOLDER FOR IRON
The best solder for iron is good tough brass； with a little borax。
143。 SOLDER FOR COPPER
Take of brass； 6 parts； zinc； 1 part； tin； 1 part； melt all together； mix
well； and pour out to cool。
144。 SOLDER FOR STEEL JOINTS
Silver； 19 parts； copper； 1 part； brass； 2 parts； melt all together。
145。 HARD SOLDER
Fuse together 2 parts of copper； and 1 of zinc。
146。 SOLDER FOR SILVER
Fuse together 5 parts of silver； and 1 part of brass。
147。 GOLD SOLDER No。 1
Take of gold； 4 parts； silver； 3 parts； copper 1 part； and zinc； 1 part。
148。 GOLD SOLDER No。 2
Take of gold； 3 parts； silver； 3 parts； copper； 1 part； zinc； 1/2 part。
149。 GOLD SOLDER No。 3
Take of gold； 2 parts； silver； 3 parts； copper； 1 part； and zinc 1/2 a
part。 The gold； silver； and copper must be fused in a crucible before the
zinc is added； or else you cannot keep them in the vessel while heating。
When all are completely fused； they must be well stirred； and run into
bars。 Solder No。1 is for gold 16 carats and upwards； No。2 is for that 14
carats fine； and No。3 for lower qualities。 If more zinc is added； it will
fuse at a lower heat； but the colour is not so good。
150。 MOCK GOLD
Fuse together 16 parts of copper； 7 of platinum； and 1 of zinc。 When steel
is alloyed with 1/500 part of platinum； or with 1/500 part of silver； it
is rendered much harder； more malleable； and better adapted for all kinds
of cutting instruments。 Note。 … In making alloys； care must be taken to
have the more infusible metals melted first； and afterwards add the
others。
151。 BRITANNIA METAL
Take 4 parts of brass； and 4 parts of tin； when fused add 4 parts of
metallic bismuth； and 4 parts of metallic antimony。 This composition is
added at discretion to metallic tin； according to the quality you wish to
make。
152。 BLANCHED COPPER
Melt together 8 parts of copper and a half part of arsenic。
153。 COMMON PEWTER
Melt together 4 parts of tin and 1 part of lead。
154。 BEST PEWTER
Melt together 100 parts of tin and 17 of antimony。
155。 A METAL THAT EXPANDS IN COOLING
Melt together 9 parts of lead； 2 of antimony and one of bismuth。 This
metal is very useful in filling small defects in iron castings； &c。
156。 QUEEN'S METAL
Melt together 9 parts of tin； 1 of antimony； 1 of bismuth； and 1 of lead
157。 IMITATION PLATINUM
This metal； or alloy； very closely resembles platinum。 Melt together 8
parts of brass and 5 parts of zinc。
158。 CHINESE WHITE COPPER
Melt together 40。4 parts of copper； 31。6 parts of nickel； 25。4 of zinc；
and 2。6 of iron。
159。 MANHEIM GOLD
Melt together 3 parts copper； 1 of zinc； and a little tin。
160。 TOMBACK； OR RED BRASS
Melt together 8 parts of copper； and 1 part of zinc。
161。 IMITATION GOLD
Take of platina 8 parts； of silver 4 parts； copper 12 parts； melt all
together。
162。 IMITATION SILVER
Take of block tin 100 parts； metallic antimony 8 parts； bismuth 1 part；
and 4 parts of copper； melt all together。
163。 TRUE IMITATION OF GOLD
Dr。 Harmsteadt's imitation of gold； which is stated not only to resemble
gold in colour； but also in specific gravity and ductility； consists of 16
parts of platinum； 7 parts of copper； and 1 of zinc； put in a crucible；
covered with charcoal powder； and melted into a mass。
164。 TRUE IMITATION OF SILVER
Imitation of pure silver； so perfect in its resemblance that no chemist
living can tell it from pure virgin silver。 It was obtained from a German
chemist now dead； he used it for unlawful purposes to the amount of
thousands； and yet the metal is so perfect that he was never discovered。
It is all melted together in a crucible； here it is： 1/4 oz。 of copper； 2
oz。 of brass； 3 oz。 of pure silver； 1 oz。 of bismuth； 2 ozs。 of saltpetre；
2 ozs。 of common salt； 1 oz。 of arsenic； and 1 oz。 of potash。
165。 MOULDS AND DIES
Take copper； zinc； and silver； in equal proportions； and melt them
together； and mould into the forms you desire； and bring the same to a
nearly white heat； now lay on the thing that you would take the impression
of； and press it with sufficient force； and you will find that you have a
perfect and beautiful impression。 All of the above metals should be melted
under a coat of powdered charcoal。
166。 TO SOFTEN HORN
To 1 lb。 of wood ashes； add 2 lbs。 of quicklime； put them into a quart of
water； let the whole boil till reduced to one third； then dip a feather
in； and if； on drawing it out； the plume should come off； it is a proof
that it is boiled enough； if not； let it boil a little longer； when it is
settled filter it off； and in the liquor thus strained put in shavings of
horn； let them soak for three days； and； first anointing your hands with
oil； work the horn into a mass； and print or mould it into any shape you
please。
167。 TO MAKE MOULDS OF HORN
If you wish to take the impression of any coin； medal； &c。； previously
anoint it with oil； then lay the horn shavings over it in its softened
state； when dry the impression will be sunk into the horn； and this will
serve as a mould to reproduce； either by plaster of Paris； putty and glue；
or isinglass and ground egg shells； the exact resemblance of the coin or
medal。
168。 TO CASE FIGURES IN IMITATION OF IVORY
Make isinglass and strong brandy into a paste； with powder of egg shells；
very finely ground； you may give it what colour you please； but cast it
warm into your mould； which you previously oil over； leave the figure in
the mould till dry； and you will find； on taking it out； that it bears a
very strong resemblance to ivory。
169。 TRUE GOLD POWDER
Put some gold leaf； with a little honey or thick gum water； （whenever I
speak of gum I mean gum arabic；） into an earthen mortar； and pound the
mixture till the gold is reduced to very small particles； then wash out
the honey or gum repeatedly with warm water； and the gold will be left
behind in a state of powder； which； when dried； is fit for use。
170。 TRUE GOLD POWDER
Another； and perhaps better method of preparing gold powder is to heat a
prepared amalgam of gold in a clean open crucible； （an amalgam of any
metal is formed by a mixture of quicksilver with that metal） continuing a
very strong heat till all the mercury has evaporated； stirring the amalgam
all the while with a glass rod； when the mercury has entirely left the
gold； grind the remainder in a Wedgewood's mortar； with a little water；