Roman — Like Paul I've not yet found this exact pattern in the Walsh factory pattern books reproduced in Reynolds, but your lovely glasses are, I think, the third example of this cut pattern I've seen. One I have in stock, a large lidded powder bowl, probably from a trinket set. Note that I've not checked it for certain — I will probably see it next in my preparations for the Cambridge Fair at the end of the month and will check it then. Let me know if you can bring a glass to Cambridge for direct comparison.
I suspect that the pattern might have been a retailer or wholesaler exclusive. We know little about exclusives, as the deal was invariably not publicised, but we have evidence for a few. We know of nonstandard colours of the Jobling Dancing Lady centrepiece for Marks & Spencer (see Baker & Crowe) and special colours and patterns made by Whitefriars for J. Wuidart & Co. There is at least one exclusive to be found in the Walsh pattern books, and I strongly suspect that an exclusive deal explains the rarity of the Walsh signature range patterns Rainsford, Leigh, and Ryde.
All glassworks would have welcomed exclusive made-to-order-only deals. Besides the obvious advantages to the retailer or wholesaler, the glassworks benefited from not having to publicise the pattern in the trade catalogue, from not having to make for and keep stock, and from not having to display the pattern in their showrooms or at exhibitions.
Don't forget to let me know if you're bringing a glass to Cambridge.
Bernard C.
