Morning journal and courier., 1888-07-02
Aluminium.

From the st. James GaZ6tt0.l
The relief that the Emperor Frederick is
said to have experienced from the substitu-
ton of respiratory tube of aluminium for
the previous apparatus made of silver has
called public attention throughout Europe to
the characteristics of what may alnost be
termed new metal. OF course 1t is nesdful
to remember the caution that post hoe is not
necessarily propter hoe; but, in point of
fact, the bulletins have given better accounts
of the august sufferer since the change was
effected. And it May be readily understood,
even by those who have neither surgical or
mechanical knowledge, that the saving of
three>fourths Of the weight of any apparatus
arti6cially introduced into the human body
cannet fail to afford relief to the patient.
The Objectionable character lowing to its
weight) of silver for the purpose is indeed
admitted by the occasional use ofsvulcanite
for similar tubes. But here, while weight is
saved, bulk is increased. Again aluminium
is practically inoxidizable, even at high tenn
peratures, except by hydrochloric acid; and
the oxide when formed is harmless and inert,
being nothing but very pure clay.
Next to silica alumina (Which is the oxide
of aluminium1 forms in combination the
Most abundant constituent of the crust of
the earth--namely clay, which is a hydrated
silicate of alumina. Lovoisier, the French
chemist, first suggested the probability of a
earths. Twenty years later Sir Humphrey
Davy verified the theory by producing the
metals sodium and potassium, and after
wards obtaining the basis of lime, stronti-
um and barytes. But the inert earth
alumina resisted the action of the voltaie
could control, and twenty years more
1 passed before the chloride of aluminium
was obtained by Oerstadt. At last, in
| 184s, Wohler succeeded in obtaining minute
beads cE globules of aluminium by heating a
mixture Of chloride of alumina and sodium.
Deville afterwards conducted some expert
ments for obtaining the metal at the court of
Napoleon ILL.,, and an expenditure of fifteen
| hundred pounds was rewarded by the fabri-
cation OF two bars of aluminium. The pro-
cess of manufacture was afterwards 40 sim
pliGed as to allow Of the production Of the
metal at about eight shillings an ounce. Ii
was manufactured from common clay, about
one-fourth of the weight of which consists
of the metal. In 1856 Rose announced that
aluRinium could be obtained from cryolite,
O mineral found in large quantities in Green
land. It was imported into Germany under
the name Of mineral soda, and used in the
manufacture of soap and also for washing
purposes. Cryolite consists of a double Ru-
oride of aluminium and sodium. when
mixed with an excess of sodium and heated
the metallic aluminiam separates It costs
by this process about aixteen shillings a
pound-haf for materials and half for the
labor and expense of the process. In the
same year the American Journal of Science
contained an account of what was called the
electrical furnace, in which q continuous
high temperature is obtained by introducing
q material of high resistance to conductiYity
into the circuit of an electric current. Af-
ter many trials coarsely puIverized carbon
was selected, both for maintaining resistance
and as reducing agent for the oxides opera
4 q mi iyfr pf xzyftH n he
oxide to be reduced is made part of an cleo
trio current in 6re-clay retort and subject
ed to the action of powerful dynamo, &c
high temperature is obtained that the
whole contents of the retort are completely
fused. Lumps of lime, sand and coruntlun
were melted, and crystallized on cooling ir
| weII-defned FORMS
By what 10 called the Cowles process (fron
the inventor of the electric furnace thus de
scribed) aluminium is now produced at the
net cost of one shilling and eight pence PEI
pound. Owing to its bulk being three timet