Wessington Springs herald. (Wessington Springs, Aurora County, Dakota [S.D.]) 1883-1891, 1890-02-28

last three centuries, Just as palnClnS mas
done. The Venetian artists in glass have
left no successors. Beautiful effects are
still obtainable in stained-glass windows
of sixteenth century relics is not indica-
tive of modern progress, or of any COM
~parison which Gun be said to be other
thar odious.
Entering a glass factory, the first object
which attracts attention is the great CEN
trail furnaces in which the glass is melt.
ed. The most unobservant person will
have noticed that ordinary glass presents
itself in three aspects-brown, green, and
stainless white or flint glass. The former
tints are due to the presence of iron-oxlde
in the sand, which is one of the princl-
pal ingredients. When colorless glass is
desired the iron has to be eliminated, or
the color masked by suitable means, and
it is a noteworthy fact that a proportion
of iron in the send too small to be indi-
Gated by the most delicate assay will i'm
part a distinct hue to glass. Different
metallic oxides impart different hues;
thus tin or arsenic will render the product
white and Opaque, gold will give q ruby
red, copper in the form Of black oxide
with a little iron ore will yield an en-
erald-greenp product; cobalt oxide a blue,
manganese a purple, oxide Of uranium a
yellow, and so on.
1t follows that where colorless glass is
desired the greatest care has to be taken
to insure the use of sand in which the
metallic oxides referred to are distin-
guished by their absence.
The furnace takes up quite a large part
OF the room in a glass factory, and is Cir
cular in form, to allow the operators to
approach the pots from all sides. The
accompanying cut will give an idea of
the arrangement of the melting-pots on
the siege or true floor Of the furnace. AS
these melting-pots are of large size (some
are ffty-fve inches in diameter) and have
to withstand continuously O heat which
will easily melt iron or steel, it follows
that they have to be made of we'll knead-
ed, tempered and annealed fire-clay.
There is a glorious uncertainty about the
life of a melting-pot. 1t may give way
and break up in eight hours, or it may
last for months. In any case the sides
wear through and get thin in the lapse of
time from the absorption of the clay
into the vitritied molten mass within.
just so long as a good pot can be patched
up and fortified it is kept in use, but when
q pot has to be removed, no matter IN
! der what circumstances, it means
a hot, hare days work for all hands. The
first thing is to dislodge the broken frag-
ments Of the pot. or the whole affair
bodily if not broken, by battering-ram
blows directed with a gigantic crowbar
into the interior of a furnace heated like
into that into which shadrach, Meshech,
and Abednego were cast in the days OF
old. When the work is completed, the
new pot, already annealed and heated to
Wilderness, has to be placed in position,
and as the pot and contents may weigh
many hundred pounds, the ordeal is
necessarily a severe one. Burns and
blisters are everyday occurrences in a
glass factory, but the visitor soon learns
one lesson. If he wishes to avoid burns
and blows he will not seek to get out of
the way y OF Tee the min: hat He viii tbe2 act ha1 mo an
independent intelligence. The man who
keeps cool in crossing a street will be