What is this close-up picture? (WotsThat: Bottom of glass bottle (from beneath))

Question

What object is shown in this zoomed-in close-up photo?

GalenaWatcher · Accepted Answer

Bottom of glass bottle (from beneath). The thick, raised bump at the bottom of a glass bottle, called a punt, was originally designed to trap sediment in wine bottles before modern filtration existed, but it also serves a clever structural purpose today by distributing stress and making bottles stronger with less glass. Glassmakers still use this ancient feature on most bottles even though we no longer need it for sediment, proving that sometimes the best designs never go out of style.

Answer: Bottom of glass bottle (from beneath)

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