Heading : A Double Series Air Twist Stem Wine Glass
Period : George ii- George III
Origin : England
Colour : Clear
Bowl : Round funnel. Good pucella marks
Stem : An air twist corkscrew inside a five ply air spiral band in which each element becomes finer as the band approaches the base.
Foot : Conical
Pontil : Snapped
Glass Type : Lead
Size :  Height 16.3cm, bowl 5.0 and foot 7.1
Condition : Excellent
Restoration : None
Weight: 121g

The central corkscrew has has an even circular cross-section. The threads within the spiral band are ovoid and have a silvered appearance, this results from the internal refraction of light and the nomenclature "mercury twist"