Glass & Glass-Making
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and the nature of the product, constitute the art of the glass-blower."
Glass is shaped, as a rule, by one of three methods-- blowing, pressing
AT WORK ON A CUT GLASS PITCHER
To give glass strength and durability it is
necessary that it be very gradually cooled, after it has been shaped.
Great care is required during the process of cooling to avoid the
uneven closing of the distended pores of the glass. In order that
the mass may cool to the same degree from its surface to its core,
ovens are employed in which the substance remains for days subjected
to a graduated temperature. This process is called annealing. Two
types of annealing kilns or ovens are used-- the intermittent and the
The first is heated and filled with glassware, then sealed
up and cooled by regulated drafts of air.
The kiln most in use at the present
time is the continuous oven, which is in the form of a long passage
with a fire at one end. An endless chain carrying pans that contain
glass objects passes slowly from the heated end of the oven to the
cold end. In this way, the temperature affecting the ware is lowered
little by little, and the pores of the glass contract evenly. To
increase the toughness of glass it is sometimes immersed while hot in
a vat of oil.
MAKING A STAINED GLASS WINDOW
||By Walter Rosenhain
||GLASS AND GLASS MANUFACTURE
||By P. Marson
|THE STORY OF GLASS
Written for Young People.
|By Sara Ware Bassett
||DECORATIVE GLASS PROCESS
||By A. L. Duthie
|THE GLASSWARE DEPARTMENT
||By Mary A. Lehmann
||ENGLISH TABLE GLASS
||By P. Bate