hi Neil - thanks very much for that information - have to admit I'd not seen a deception in that shape. Just goes to show. I see the ordinary sort quite commonly - will have to keep an eye out for your sort

I had in fact just typed some waffle and you pipped me to it, but I've amended slightly my comments, but will let the rest stand - if you have any further comments re these things please do share.
""pix of some 'deception' glasses attached.....they seem to come in this wine/sherry/port shape rather than ale shapes (however, see Neil's enlightenment on this matter).

You can see the thickness of the walls, and the inside of the bottom of the bowl which almost always comes to a blunt point. The smallest one (at the front), is pressed as opposed to being blown like the others - but must admit I'm in two minds as to whether it might not even be a penny lick - although with licks the bottom of the bowls seem to be flat usually, not pointed.
The Y and T marks - being produced by the gadget - is supported by authors such as Charles Hajdamach, R. Wilkinson, John Brooks - it was just that some time back I referred to this fact and was told the effect was produced by 'shearing' the pontil attachment. I'd suggest that not all these authors can be wrong, so perhaps we should go back to saying 'definitely the result of the gadget'.

Marks on the top of the foot seem very difficult to see, and probably even worse to photograph.
Colour of glass varies, and a pale almost straw tinge is found occasionally - might indicate soda glass, possibly. This item is a drawn stem variety - a two piece glass where the bowl and stem are formed from one lump (as opposed to the more usual three separate parts of bowl, stem and foot). The stem being drawn away from the bowl metal, then the foot made and added separately.
Sometimes known as drawn shank or straw stem, to separate them from a stuck shank glass (the three part job).
The occasional lack of wear on a gadget marked glass might indicate that these have been taken from old stock that had perhaps been stored and hardly used - I've seen a few examples.
These glasses can be found without a Y or T mark, but with a period look, and at the underside of the foot show an almost spiral looking impression in the centre.............thought to be an improvement on the gadget or some variety of same - later than about 1870.""