Narrator: Glass makers use molds to create duplicate vessels such as
this pair of glass flasks. The process begins by placing molten glass into a mold. By inflating, the glass
takes the shape of the mold. Once removed from the mold, the bottom is flattened
and the neck shaped. A pontil is attached to the bottom and the vessel is freed
from the blow pipe. The vessel is reheated and further refinements
are made to its shape. (silence, showing example)