Film clip is compliments of the Owens-Illinois Glass Company.
(Many thanks to Phil Perry, engineer with that company.) Mouth-blown utilitarian bottles have several important diagnostic characteristics which can be helpful for dating.
The mold boy would open and close the mold (at the base of the pipe behind the wash tub) as directed by the gaffer.
A second boy looks on with (possible) admiration of the gaffer as they were the highest paid and most elite workers on the glass factory floor and among the highest paid of all skilled laborers during the 19th century (Barnett 1926).
It was also the position that glass factory boys aspired towards (Skrabec 2007).
But when it comes to alcohol, where expiration dates are rarely available, how can we be sure our spirits are still sippable?
While we know certain types of alcohol, like wine, can improve with age, what happens when a bottle has already been opened?
If you are seeking information on what type bottle you have, go to the Bottle Typing & Diagnostic Shapes page which also will lead users to additional dating information.