121. Near Castle Inter Lucus
“We heat sand and beech ash together
in this furnace. Master Gausman called
this first step ‘fritting.’ Ernulf and I
have been making frit for three weeks now, saving up a good supply. The frit furnace isn’t hot enough to melt
sand, but settles the ash and sand together.
Two days ago we moved to the second stage, with the main furnace.”
Stacked firewood lined the north
wall of Isen’s A-frame glassmaking factory.
Students of Collegium Inter Lucus
stood with their backs to the wood, watching and listening to Isen’s
lecture. Besides the frit furnace and
the much taller main furnace, there were workbenches and mysterious looking
tools hanging from hooks. The glassworks
was very warm, even on a late winter morning.
Marty wondered what it would be like come summer.
A
group visit to the glassworks was Marty’s idea, inspired by grade school field
trips in his childhood. The excursion
served as a break from daily lessons for the children, and it honored Isen’s successful
launch of glassmaking between the lakes.
Marty had already asked Ora to plan a “Grand Opening” for the
glassworks, to which villagers in Senerham and Inter Lucus would be invited.
“To actually make glass, we put some
frit in a crucible—that’s a special bowl that won’t crack even when it’s very
hot—and it goes into the main furnace.
We put in a crucible this morning, before you all had breakfast, and
either Ernulf or I have been feeding the fire and watching the furnace all
day. The frit in the crucible has melted
into glass, so now we’re ready to blow.”
Isen put on a pair of thick cloth
gloves and held up a clay tube about three feet long. “My blowpipe.
The other end has to be hot to gather glass.” Ernulf, also wearing gloves, opened a small
door on the furnace, and Isen inserted the blowpipe. Sweat sheened on Isen’s face as he rotated the
tube for several minutes. “And now we
pick up a gather.” Isen squatted to face
the opening of the furnace and moved the tip of the tool into the white-hot
liquid in the crucible. Most of the
children couldn’t see into the furnace, but those immediately behind Isen
watched the tip of the blowpipe intently.
Isen slowly backed away from the
furnace with a round bulb of glass hanging from the tip of the blowpipe. Marty heard a collective intake of breath
from the onlookers. “Oh! Look at that!
Wow!”
Isen swung his instrument in a small
circle while puffing little breaths into it. Ernulf shut the door to the
furnace, reducing the tremendous heat coming out, and picked up two flat wood
paddles. The apprentice stood ready to
respond to any gesture from Isen while the molten gather on the end of Isen’s
tool became a round ball. Isen lowered
the glass ball onto the concave surface of a wooden block, puffing and turning
the glass. Marty was struck by the image
of a jazz musician improvising.
Occasionally Ernulf used the paddles to help shape the glass.
Isen
flicked an elbow toward the furnace without lessening his attention on the
glass ball, which was now about six inches wide. Ernulf quickly set aside the paddles and
opened the furnace door; Isen reinserted the glass ball. He continued turning the glass while speaking. “I’m reheating the glass a bit so I can work
it. Some furnaces have a special door
for this part; they call it the ‘glory hole.’
But we built our furnace simple and use just the one door. Course, I have to be careful not to touch
anything inside.”
Isen
brought out the glass ball, and Ernulf closed the furnace. Once again Isen worked the glass on the
wooden block, but now he drew the top higher, and Ernulf’s paddles pushed the
slowly rotating piece into a cylinder shape. At a signal from Isen, Ernulf picked up a tool
that reminded Marty of a giant set of tweezers; with the iron tips Ernulf began
cutting the cooling glass a few inches from the blowpipe. But the workmen did not cut the piece
completely free; first, Isen moved it to a wood bench and let the weight push
down to create a flat bottom. They
placed the vase—for that’s what the piece looked like—on two metal rods. Isen finished cutting free the blowpipe and
the bit of glass affixed to it and handed it to Ernulf, who scraped off the
excess glass into box that contained other such bits. Glass was too valuable to be thrown away; later
the scraps would be melted and made into new pieces.
The
top edge of Isen’s vase was still pliable; he shaped it with smaller wood tools
to smooth out irregularities. Then
Ernulf climbed onto a stool to open a door high on the furnace. Isen picked up the vase they had made on its
punty rods and they slid it in.
“If
glass cools too quickly,” Isen explained, “It’ll break. So we put it in the ‘annealing oven.’ It’s above the main furnace and not as hot. We’ll let the new piece cool slowly. In a day or two we’ll take it out. If it cracks or if I don’t like the color,
we’ll toss it in with the cullet.” Isen
indicated the box of glass scraps.
“Later, we’ll smash the cullet down into bits so it’ll melt easier, and
make something useful.”
Isen
took off his gloves. “Glass making takes
lots of firewood ’n lots of practice.
Ernulf here has been learning real fast, ’cause he grew up ’round his
dad’s smithy.”
The
students asked questions.
“Could
you put a handle on the vase shape and make a pitcher?”
“How
do you make glass of different colors?”
“The
‘gather’ came out round like a ball—how do you make it flat and square for
windows?”
“Will
you make things for Inter Lucus?”
“People
from Senerham will buy glass too, won’t they?”
“How
many glassmakers are there in Down’s End?”
Lots
of questions, questions that validated Marty’s choice of students. They
have genuine curiosity; they want to learn how things work. They see that a glassworks will bring change
and they’re thinking of the big picture.
Manufacturing glass here at Inter Lucus might lead to competition with Down’s End. It might lead to trade with other places.
“Can
you make a glass string?”
Alf’s
voice, piping from the end of the line of students, interrupted Marty’s
reverie. Isen hesitated before
answering. “Yes. Glass can be shaped without blowing it.”
Isen
picked up an iron rod like the ones they had used under the vase. “If I pick up a gather with a punty rod like
this one, I can’t blow into it. But I
can draw it out into a string of glass, and I can fold it and mold it. Then, once it cools, the string will have
whatever shape I gave it. With practice
I could make a brooch, for example. The
kind of thing rich aldermen in Down’s End give to their wives.” There was a kind of longing in Isen’s voice; he
had told Marty once of his dream of making a glass swan and other beautiful
things.
Alf
asked, “Could the string be straight?
And very, very thin? It wouldn’t
have to be long.”
Isen
was puzzled. “Making a straight bit of
glass would be easy, especially if it is not long. But why would anyone want such a thing?”
Tayte
Graham said, “A glass hairpin would be pretty, but it would break. A glass needle could be really sharp, but
again, it would break.”
Alf
ignored Tayte’s suggestions. He was
looking up at the A-frame walls as if she weren’t there. “Very thin.
Very straight. And they have to
be…smoked.”
At
first, Alf’s strange choice of words elicited derision. Someone said, “You smoke meat, not glass,
silly!”
But
then Ora said, “You’ve been dreaming again, haven’t you, Alf?”
The
boy sighed deeply, and he looked at Marty.
“Aye. I dreamed it. For the CPU.”
Here ends part three of Castles.
Copyright © 2014 by Philip D. Smith.
All rights reserved. International copyright secured.
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