very unusual - sorry to seem thick John, but why the bluish effect?
T/Webb were granted two separate Registrations that day - 298626 and 298627 - both parcel 9, and both are shown in Gulliver as side elevation, but only half of each hat is drawn - no idea where the author sourced his drawings - not I don't think from the Board of Trade drawings which show both in full outline, unless Gulliver decided to save space by reducing the size of the drawing.
TNA Register omits any description of either, but Gulliver has written 'top hat' against 298626, and 'bowler' against 298627 - and this does look to be a good description bearing in mind the shape of each - and he describes these as 'flower holders'. As usual there is an absence of dimensions on the original factory drawings.
I hate to cast nasturtiums but is it possible this one has been pressed some time in the intervening years? I can post pix of the factory drawings if it's of any interest - let me know.