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Vacuum Breaker: A device that relieves the partial vacuum in pipelines to
prevent back siphonage.
Vacuum Distillation: (1) Distillation under reduced pressure (less the atmo-
spheric) that lowers the boiling temperature of the liquid being distilled. This
technique with its relatively low temperatures prevents cracking or decom-
position of the charge stock. (2) Distillation under reduced pressure, which
reduces the boiling temperature of the material being distilled sufciently to
prevent decomposition or cracking. See Distillation.
Value-Added Industries: Digging stuff up and doing something to it so you
can sell it for more than stu