Until recently, I had only seen one example of the Sowerby pattern 1257 small vase. It was in white vitro-porcelain, and only bore the Sowerby peacock head trademark.
(Permission for the re-use of this image on the GMB granted by jolieroger8nn6).
It is illustrated on page 4 of the Sowerby pattern book IX -1882, but Cottle does not link it to any design registration, so I had assumed that it was from an unregistered Sowerby design.
Currently on eBay there are two vases in the same pattern (one in blue malachite and the other in green malachite), but this time both vases bear the Sowerby peacock head trademark AND a registry date lozenge for 18 September 1877 – Parcel 7. See:
http://www.ebay.co.uk/itm/2-Rare-Sowerby-Green-Blue-Slag-Glass-Vases-Registered-18th-September-1877-/200953598693?pt=UK_Art_Glass&hash=item2ec9c492e5Slack (p51) has a page from the Sowerby pattern book VIII – 1880, showing a pattern 1257 vase in brown malachite, but I have yet to come across an actual example in that colourway to check whether it bears a lozenge or not.
The 18 September 1877 lozenge corresponds to a bundle of 20 registered design numbers (RDs 314265 to 314285), and Cottle allocates specific pattern numbers to each RD number within the bundle (ranging from pattern number 1237½ to 1261¾), BUT 1257 is nowhere to be seen in that allocation.
Of those 20 allocated registered designs, I only have photo references for four – 1258 (RD 314277), 1254½ (RD 314279), 1240 – the Gladstone Bag (RD 314283), and 1256 (RD 314284).
Thompson (p31) only shows an illustration of 1240 – Gladstone bag as corroboration.
If Paul S. drops in on this topic, I wonder if he would mind looking at his photos of the Sowerby design representations covered by this lozenge bundle, firstly to see if there is a representation of pattern 1257 corresponding to a particular design number and then, if possible, to confirm that the Cottle attribution of particular Sowerby pattern numbers to the actual design representations within that bundle is correct, please?
Fred.