The bottles are filled upside down, and pressure of the gas in the bottle forced the marble against the washer, sealing in the carbonation. The bottle is pinched into a special shape to provide a chamber into which the marble is pushed to open the bottle.

How do you drink a Codd neck bottle?

Codd also devised a bottle opener to be inserted into the bottle's neck to push the marble down to 'open' the drink and let the trapped gas escape. Although Codd's opener was widely used in public settings, privately most people simply used their little finger to push the marble down.

What was a Codd bottle used for?

This bottle was used by Stotherts of Atherton to store carbonated drinks. The bottle is embossed with the image of a bearded man.