I'm sure the experts are very much aware of the following, and hope they don't find this too boring (much of which has been said before, of course). Apparently Webb called this particular surface pattern 'Venetian Ripple' (this piece measures about 7" x 7"), and for me, I see it on my travels as the most common finish after 'Old English Bull's Eye'. Surprisingly, I have yet to find a 'Plain' finished piece, and I guess the remaining finish, the 'Water Lily' design, is the most uncommon. Also, surprisingly, I've yet to find a piece of either 'Spring (a delicate shade of green akin to Eau-de-nil, apparently), or 'Evergreen' (a darker sort of Bristol Green) - why should this be so - were the 'greens' unpopular, or made in vastly lesser quantities?? If you read H. W. Woodward's book he unfortunately confuses the colour issue with regard to 'Amber' and 'Sunshine Amber', and refers to both simply as... "Sunshine" (golden amber), without making the distincton between those pieces containing uranium (Sunshine Amber) and the non uranium examples (Golden Amber) - and whilst the
latter former [ * ] are perhaps the less common variety, they do exist in reasonable numbers. There is no doubt that Woodward's book is of much value, since there is almost nothing else of reference on Webb (apart from some data in Charles R. Hajdamach, and Roger Dodsworth's 'British Glass Between The Wars') - but his four and a quarter lines on 'Gay' glass is paltry to say the least (and lacking a single illustration to boot). We could do with someone producing something weighty on Webb. Picture four is, of course, 'Golden Amber' (non uranium) - which you will all know, which seems to be a hue given to quite noticeable variation in depth of colour. Does anyone know if this particular bowl is a common pattern, or scarce?? - I'm sure I haven't seem an example previously.
References: 'Art, Feat And Mystery (The Story of Thomas Webb & Sons, Glassmakers) - H. W. Woodward - 1978.
20th Century British Glass - Charles R. Hajdamach - Antique Collectors Club 2009.
'British Glass Between the Wars' - Roger Dodsworth (Editor) - 1987
[ * ] Mod: edited in accordance with later comment by Paul.