r to cool. Any
current of cold air that strikes it will fracture it. So, as you can
readily see, an annealing kiln or oven must be arranged in such a way
that it will allow the two surfaces to cool simultaneously."

"I think I understand," answered Jean. "And you say these things must
stay in the kiln about three days?"

"Yes, the kiln takes about that time. It is a slow process, because we
have practically no way of regulating its heat. A lehr does the work
much quicker. Over here you will see one. It is a long arch or oven
open at both ends. The glassware travels in iron pans along a moving
surface from the hot oven, or receiving end, to the cool, or
discharging end. The temperature of the lehr can be scientifically
tested and regulated, and this is very necessary, because the heavy
glass intended for cutting can stand a greater heat than can ordinary
hollow ware such as vials and table glass. We regulate the oven
according to what we are annealing in it. It does not take so long to
anneal glass in a lehr as in a kiln, and therefore in many factories
only lehrs are used. If you will come around to the cool end you can
see some of the finished pieces being taken out. Each object is made by
a certain set or gang of workmen--a shop, we call it. The work of each
shop when taken from the lehr is put in a box by itself and is then
counted up, and the men paid according to the number of perfect objects
finished. It is piece work. For instance, one shop makes only pitchers,
another wine-glasses, another vases, and so on. Every group has its
specialty, and each workman in the team understands exactly what his
part is in the whole. The common interest of turning out as many
perfect pieces as possible spurs each man to work as rapidly, well, and
helpfully as he can."

"Just like a football squad, Uncle Bob," laughed Jean.

"Exactly," nodded Mr. Wyman. "After the finished glass is taken from
the kiln or lehr it goes to the examining room, where girls dip it in
clear water and hold it to the light to test it for imperfections; then
it is sorted, packed, and shipped."

"And vases, sugar-bowls, tumblers, and most of the hollow glassware is
made in the same way?" inquired Mr. Cabot.

"Yes, practically so. The general scheme is the same. As I told you,
there are some difficult designs which must be squeezed into shape in
moulds. These are of iron, and for the convenience of the blowers are
set in holes in the floor. They are ma