For reference a Stevens and Williams Caerleon vase, circa 1930. It is a big old beast, 28cm tall and weighing in at 3kg. Applied snake, rim and foot, snapped pontil mark. Clear glass with small blobs of blue and green, iridescent. This shape mentioned on page 109, 20th Century British Glass by Charles Hajdamach, a couple of the other shapes are pictured on page 110.
I decided to snap a photo of it in the remains of the Roman amphitheatre down the road in Caerleon but had not anticipated several bus loads of schoolkids enacting a battle between Romans and Celts. Not sure if that was a Roman or a Celt creeping into the frame...
John