reminds me of Walsh 'Pompeian' or even Nazeing, though less so perhaps. In profile, the bowl shape is like Bagley's elf posy vase with the central cavity and distinctive rather late 'deco' shape - in fact I don't think it's either really, but those might give a good idea of the bubbled effect, and shape.
About 6 cms. high and c. 24 cms. max. diameter. I forgot to photograph the pontil area - it's been ground out but lacks finesse and has been left matt, and there's enough wear to take it back to 1930 - 1950 possibly. thanks for looking and all suggestions appreciated.