Two mixed-twist stem wine glasses and an opaque-twist flute, circa 1760

One glass probably Dutch with a bell bowl, the stem with a multiple spiral air corkscrew with heavy white spiral threads, 17.4cm high, another wine glass with a lipped cup-shaped bowl, on a double series opaque-twist stem with an extra air cable, 15.9cm high, the opaque-twist wine glass or flute with a drawn trumpet bowl on a slender stem containing a single multi-ply air corkscrew, 18.3cm high (3)

Provenance
Robert Manners Collection