In the Nineteenth Century, soda bottles typically had round bottoms. Why? Rain Noe of Core77, a “lapsed industrial designer”, explains that these were made before the 1892 invention of the crowned metal bottlecap, which snugly keeps the carbonated contents inside. At this point in their design history, soda bottles were topped with corks.
When corks dry out, they break down and, eventually, fall out. To keep them moisturized, it’s necessary to maintain contact with the liquid inside. That’s not possible if the bottle is resting on the bottom. So glass blowers made round bottoms for the bottles so that they had to be stored on their sides.
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