oxide of copper; while the bluish malachite is
pure carbonate of copper; and that lovely
peacock ore of all imaginable colours, so richly
scattered through the Burra Burra mines, is copper
pyrites; and that queer-looking mass is arseniate
of copper, or copper and arsenic, the crystals of
which smell of garlic when heated, and run into
metal when burnt to death with charcoal as their
companion.

Very different in its different conditions is
that one same substance — phosphorus. As
phosphorus, pure and simple, the soft white waxy-
looking residue of burnt bones, it takes fire in
the open air, and by the heat of the hand alone;
and by a strange bit of homœopathic revenge,
though itself the product of bones, in its use and
manufacture it destroys the jaw-bones of workmen.
As amorphous or red phosphorus, that
is, common phosphorus highly heated and stirred,
it will not take fire save under certain special
chemical combinations, and is so thoroughly
innocent that it may be eaten with impunity.
This amorphous phosphorus is the secret of
our new safety-matches, for nothing in the way
of friction can make them ignite unless they are
rubbed on their own peculiar sand-paper—the
sand-paper being phosphorised, and the matches
tipped with sulphur and chlorate of potash,
which is the only combination tending to flame.
Wherefore, because of its harmlessness in the
making, and its safety in the using, amorphous
phosphorus is to be patronised for matches
instead of the deadly and dangerous form of bone
essence employed. Phosphoric acid has lately
been found to be good for the over-tasked
brain; being, in fact, the reparative power of the
brain, and the cause of healthy mind-work.

Then there is a vast deal to be said on this
white pleasant-looking stuff called soda; to be
had from certain mineral waters, or from the
ashes of the seaside plant, salsola — soda — so
largely cultivated by the Spaniards at Alicante,
and when burnt known as sweet barilla — or from
the burnt sea-weed known as kelp, which now,
however, is chiefly used for giving iodine. Le
Blanc was the first manufacturer of soda, having
Philippe Egalité for his partner, but poor Le
Blanc did not make a fortune, as some others
have done lately, and shot himself in despair,
when poverty clutched him too tightly by the
throat. Now, hundreds and thousands of tons
are made weekly, to the devastation and
destruction of the vegetable world for miles round.
But no soda manufacturer could get out of the
fatal consequences of scorched grass and
poisoned trees, till Mr. Gossage invented
something—unintelligible to me what—for
collecting the muriatic acid gas, which does all the
mischief. If the manufacturer will build a good
Gossage tower, the making of soda need not
absolutely destroy every bit of vegetable life as
far as the vapour of the muriatic acid can reach.
Every one knows what soda is, from the
laundress at her tub to the afflicted with "acid,"
who keeps his little paper of carbonate of soda
beside him as a usual after-dinner corrective;
but every one does not know that this pure
white innocent lump is caustic soda, and that, if
you touch it, your flesh will be burnt to the
bone; nor that this white mass, called sodium,
the "metallic base" of soda, would, if broken in
the air, go off into a flame, and that water
kindles it, and nothing puts it out again. Then
there are some long silky crystals rose-red, called
palladium salts, and some long silky crystals of
pure scarlet, called iodide of mercury; and
specimens of gold and gold-leaf, white, greenish,
yellow, and coppery, rhubarb-coloured, brown
(for gilding porcelain), and heroic red—the gold-
leaf made of the best gold, else it will not hammer
into sufficient thinness, but breaks and goes
off into flakes, and cannot be beaten into its
hundred square feet of leaf from the ingot of one
square inch or one ounce (troy); and glittering
spangles of native gold, and a few specimens of
Welsh quartz, I think it was, with actually half
a dozen minute scales of gold glittering through
the grey! and pretty rock of quite pure gold;
and gold dissolved by chlorine, very bright, and
used in photography.

And then there are the silver specimens—
silver dissolved in nitric acid, making the nitrate
of silver — also for photographers' use; called
lunar caustic when melted, and capable of
blackening any amount of flesh; and there is the case
of German silver, which is a dull mixture of
nickel and copper, and not to be encouraged by
the lovers of the beautiful; and specimens of
sulphur; and a pretty pale-yellow powder called
tannin, and another, paler still, called gallic acid,
and gallic acid crystallised; all got from oak-
galls and used for dyeing. And there is a
crystallised hollow sphere of bismuth, good, as
the "sub-nitrate," for making pearl-white, which
pearl-white is used by ladies for their faces, by
potters for their enamelling, and by doctors for
"cordalgia," or heart-ache of some kind; also,
with a slight difference of preparation, good for
making an invisible ink, to be brought out by
plunging the paper written on, in water. This
nitrate of bismuth mixed with tin makes a
mordant for all violet tints in calico printing. And
there is another crystallised hollow sphere, soft
and waxen, but this is only camphor, about
which I do not think it worth while to cudgel
my brains, beyond the very patent example of
camphor balls for winter chaps; and a greyish-
coloured half hollow sphere, crystallised, of
muriate of thebaia — what is that? — to be
noticed because of its beauty, and another,
lighter coloured, of like form, close to it, called
papaverine, and another of codeine, larger and
lighter still, and a lump of morphia pure white:
and I believe all come from the same mother,
and mean the same thing, namely, the essence
of poppy, or opium under scientific disguises.
Then there is a very pretty bit of antimony,
called star regulus, like a dusky bit of tarnished
silver with fern-leaves engraved on it, and a
column of crude antimony, like a stalactite
column, and printers' type cast from the metal
alloyed; for type-casting and eye-blackening are
the two principal uses of antimony that I know of.

A large ugly brownish-grey mushroom-