Has anyone seen one of these?

[Roy]

That's interesting. Is the air vent dating information peculiar to A.G. Smaller & Co bottles; or, is that a manufacturing technology that can be found among products from several glass houses but didn't exist prior to 1892?

Good question Will.
I have a small brown flask with 3 small bumps on the bottom and I've been wondering why they are there. Maybe for venting also. Roy

 

[Len]

Maybe they were originally the vent holes that when cooling had the glass cover them and harden... I don't get why they're all so uniform...

 

[Roy]

Good question Will.
I have a small brown flask with 3 small bumps on the bottom and I've been wondering why they are there. Maybe for venting also. Roy

Here are a couple of pictures of another strap sided flask with 3 bumps on the bottom. Possibly for venting ? Roy