I was wondering about the domed base of some of the bottles.
Luckily there's a 'Bottle Bases Page': https://sha.org/bottle/bases.htm
> It may appear that the steep rise or pushed-up portion of the base was done to reduce the interior volume of the bottle. However, it was more likely done for some or all of the following reasons: for bottle strength enhancing, stability (i.e., the process helps form an even base and keeps the rough glass of some pontil scars out of the way so the bottle sits upright without wobbling), to provide a means of turning bottles in a stack using the fingers and thumb (a procedure still followed in traditional champagne manufacture), and/or possibly to trap content sedimentation (Jones 1971a; Boow 1991).
> It may appear that the steep rise or pushed-up portion of the base was done to reduce the interior volume of the bottle. However, it was more likely done for some or all of the following reasons: for bottle strength enhancing, stability (i.e., the process helps form an even base and keeps the rough glass of some pontil scars out of the way so the bottle sits upright without wobbling), to provide a means of turning bottles in a stack using the fingers and thumb (a procedure still followed in traditional champagne manufacture), and/or possibly to trap content sedimentation (Jones 1971a; Boow 1991).