These last two Reg. Nos. - 800439/40 - appear in Baker & Crowe, also in The Glass Association Blue Book, which is what you'd expect for decorative glass designs, and occasional cross-referencing between these two sources can sometimes be useful in order to confirm Reg Nos. and the relevant Registrant.
There are perhaps another dozen or so Jobling design Registrations, which appear in the Blue Book - from the '30s and mid '40s - but which aren't included in the autthors' list of decorative glass items - and in fact there are two items in Baker & Crowe from '46 and '47 which come after the closing date of the Blue Book.
Obviously the compilers of the Blue Book included every item of whatever nature provided it was glass related (BoT CLASS 3), and appear not to have made any distinction between aesthetically decorative glass and humble Shippams paste pots. Occasionally they slipped up and glass items are known to have been omitted from the Blue Book due to being placed in the wrong CLASS. Generally, Jobling Rd. Nos. that occur in the Blue Book only are doubtless not decorative glass in the sense we understand, since this factory produced many designs for domestic and commercial lighting, and none of those appear in Baker & Crowe, who seem to have been methodical and accurate when making the distinction between decorative glass and lighting designs - in fact their own list is described as for ' ...... decorative glass designs'.
However, coming back to the above two Rd. Nos. - and for those who have both publications - there is an apparent anomaly insofar as Baker & Crowe show only those two Reg. Nos. for 19.02.1935, whereas the Blue Book shows five Nos. for the same date - 800439/43 - so, for whatever reason the last three Nos. in the sequence aren't included on the Baker & Crowe list - and having now seen the missing Nos. can confirm they aren't lighting items. It's a known feature of Jobling's catalogue numbering system that one or two designs were repeated, on different shapes occasionally, though such few examples look to have always been given individual Reg. Nos. - for example cat. No. 12000 for the fish motif.
Is the absence of these Nos. from their list a deliberate act by Baker & Crowe - who were aware of them, but considered earlier Registration didn't warrant repeating the design? Or might it have been the utility appearance that meant they didn't qualify as decorative glass? or some element of both? - but I'd suggest that most of us would consider it necessary that all Reg. Nos. should be included to avoid this sort of confusion.
The Blue Book wasn't published until some eleven years after the Jobling museum catalogue, though Baker & Crowe do acknowledge the Registers of Designs (The Patent Office - London) in their list of source material, so we might assume they had seen that 19th February 1935 contained five separate Registrations.
Here are details of the three Reg. Nos. from 19.02.1935, not included in the Baker & Crowe list:-
Reg. 800441 - a style of double dish, perhaps intended for nibbles/bon bon/peanuts - it looks to have some opalescence in the centre. I could be very wrong, but this design doesn't appear to have any precedent amongst Jobling's other designs?
Reg. 800442 - a lidded jar with identical criss-cross pressed pattern which matches Jobling's catalogue No. 2583 - the 'salad bowl' from Registration 805376 dated 10.08.1935.
Reg. 800443 - again we're back to the pressed three-footed salad bowl catalogue No. 2583, and I don't see any apparent difference between this image and 805376, so I'm wondering if 800443 might just be Registering the similar footed milk jug showing in the same photo, rather than the salad bowl.
Interesting to see how the original photographer has tried to improve contrast by filling the cavities with either black or white paper, though I'm not sure it really helps. Pix attached for all three missing Registrations. Does anyone have examples to show of the double dish for nibbles, or the milk jug?
Appreciate there are others here who have collections of Jobling and are better informed as to production details - so look forward to their input and comments on this matter - thanks:-)