sheet of crown glass just where a lump of hot glass was
attached so the blower could whirl or spin it from the middle and make
it into a flat disc. But, as you can readily understand, a sheet of
glass with this mark or defect right in the center will never cut to
advantage, and therefore only comparatively small pieces can be got out
of it; there is much waste. Yet, as the man says, it has a wonderfully
brilliant surface. Now I am not going to let you stay here any longer
or we shall not have time to see the part of the factory where I am
working. I'm in the plate glass department, and I intend to drag you
off to the casting hall this very moment."

Jean laughed.

"Before you go, though, you must understand that plate glass is quite a
different thing from these others. It is not blown at all. Instead the
melt is poured out on an iron table just as molasses candy is turned
out of a pan to cool. You'll see how it is done."

They crossed the yard and entered another part of the works; Giusippe
gave the foreman a word of greeting as they went in.

On each side of the great room were the annealing ovens, and down the
center of the hall on a track moved a casting table which rolled along
on wheels. The pots of molten glass or metal were first taken from the
furnaces and carried on trucks to this casting table. Here they were
lifted by a crane, suspended above the table, and then tilted over, and
the glass poured out.

[Illustration: "THE MELT IS POURED OUT ON AN IRON TABLE"]

"For all the world like a pan of fudge!" declared Jean.

Giusippe laughed.

"I guess you would find it the stickiest, heaviest fudge you ever tried
to manage," said he.

The instant the mass of soft metal was on the table a roller of
cast-iron was passed very swiftly back and forth over it, spreading it
to uniform thickness, and at the same time flattening it.

"The thickness of the glass is gauged by the strips of iron on which
the roller moves," explained Giusippe to Jean. "These can be adjusted
to any thickness. Notice how rapidly the men have to work. The glass
must be finished while it is hot, or there will be flaws in it. It is a
rushing job, I can tell you."

"But--but you don't call this stuff plate glass, do you?" inquired the
girl in dismay. "It does not look like it--at least not like any I ever
saw used as shop windows or for mirrors."

"Oh, it is not done yet. But it is what we call rough plate. That's the
kind that is used w