fact that a wire, one-eighteenth of an inch in
diameter, can support a weight of three hundred
and sixty-one pounds. So, after all, it has a
right to be called white gold, and of royal standing
in the metallic world. It is used in
ornamental porcelain, to give a steely lustre to
figures and surfaces, as gold is used to gild
them; and a certain preparation called platinum
black — how made I don't in the least comprehend—
can be used for fumigating rooms, by
giving them the odour of vinegar if spread upon
a watch-glass moistened with alcohol; and if
introduced into a mixture of air and inflammable
gas, causes an explosion as if it were fire itself.
But its chief use is for chemical cups and vessels.

As we went further I saw some "platinum
salts," which looked like sugared bonbons; and
some granulated melted platinum, for all the
world like the new American corn sweetmeat;
and some blood-red platinum something; and
one very beautiful ingot, perfectly pure, all
hacked and cut like a rock, but a little dusky
looking, and neither like steel nor silver. Then
there was a lovely bit of granulated silver, like
frosted rock-work, white and moony, obtained by
pouring melted silver into water; and another
bit of like form, appearance, and generation—
only this was yellow gold instead of moonlight
coloured silver—the sister and the brother keeping
guard at each side of the case.

Then there was the aluminum case with its
great gorged falcon cast in one piece, and other
things full of interest and information.
Aluminium, or aluminum, as it ought to be spelt,
is what chemists call the "metallic base" of
clay, as alumina is the "earth" and alum the
"salt;" the metal of the ordinary common clay
of the fields and wolds, where it has lain
unnoticed and undiscovered from Adam's day to
Sir Humphry Davy's and Wöhler's, while
millions of generations have walked heedless over
it, and not even chemists have suspected that
they had a precious metal at their feet. It is
only quite of late years that it has been
made use of; but lately the whole woman world
has decked itself out in those pretty light silver-
grey ornaments, which are to be bought for a
trifle, but which look well and simple when their
form is good. They have been trying to make
aluminum do more serious service than make
brooches and buckles and buttons; they have
proposed it for pianoforte wires, chemical balances,
barometers, &c., and they have found it good for
reflectors — better, indeed, than silver — because
it does not blacken or tarnish, even when placed
in a solution of sulphur; and they have been
concocting a very beautiful looking metal, which
they call "aluminum bronze," an alloy of
aluminum and copper, and which they say likewise
does not tarnish. But can copper be mixed
with anything and not get dull and dirty?
Aluminum is marvellously light, a sixth only of
the weight of silver, and so little resonant that
a huge bell as big as Big Ben would give out
only a tiny little tinkle, very sweet and silvery,
but utterly useless as a tocsin or a warning.
The ruby, sapphire, oriental amethyst, topaz, and
emerald, are all nothing but the crystallisation
of aluminum, or alumina rather; bits of mere
clay and marl, coloured in various proportions
with oxide of iron; ninety-eight of clay (alumina),
and the remaining two portions divided between
the colouring matter and minute fractions of
something else! This alumina, or the "earth of
clay," is the chief constituent in the fine porcelain
clay or kaolin used in our higher manufactures,
giving it ductility in working, and tenacity
in baking; it is also a mordant — that is, fastens
certain colours on to printed cloths and calicoes;
and the painters' colours called lakes are colours
prepared with alumina. Pottery and colours
are the chief uses to which we have put alumina
as yet; and the creation of some of the most
precious gems is one of the smallest uses to
which it has been put by nature.

Then comes the "salt" or alum, which is got
out of alumina by some tremendous process
utterly unintelligible to the uninitiated. Alum
is represented in the Eastern Annexe by a huge
white serpent with a red tongue, a large white
dirty-looking open-worked column, and by big
blue and red crowns and runic crosses, just like
the children's baskets to be had for sixpence at
the bazaar, only on a magnified scale. But alum is
a very beautiful thing after all; as for the "hair-
salt alum," or — let me take breath and mind my
spelling — "schistose sulphate of magnesia," it is
one of the most lovely little dainty feathery bits
of scientific nature to be found in the building;
but I own I slacken a little in my admiration
when I learn that hair-salt alum, or schistose
sulphate of magnesia, is nothing but my old
enemy, Epsom salts, in a more relined form and
with a grander name. This grey and speckled
mealy-looking stuff is what alum is made from,
and is called alum schistose; it is not ugly,
though nothing like the soft frosted work of the
hair-salt alum. Alum has various uses; among
them, it makes wood incombustible; gives hardness
to candles; clears turbid water (do not the
Chinese clear their worst and most brackish
waters by a lump of alum properly
proportioned?); it is used in tanning and dyeing
leather, and in the silvering and lacquering trades;
a pinch put into a churn bewitched, and when
the butter will not "come," separates the water
from the cream and produces the result— butter;
it is an antidote to the painters' disease — the
lead cholic; is a mordant in dyeing and printing
calicoes; is used by book-makers in their paste,
and by London bakers in their bread (the
wretches!); and it was the cause of a monster
chimney, a huge fortune, and a damaging
lawsuit, when the Pendleton people tried to pull
down Mr. Spence's chimney — three hundred feet
high — which he had built for his "ammonia
alum works" at Manchester, declaring that they
would not be poisoned by the fumes, let what
would be the consequences — the manufacture of
alum not being considered the most savoury
imaginable. This same Mr. Spence exhibits a
lump of alum, of three tons and a half weight,
natural size; and a noble white mammoth it is.

Presently we come upon a case where a