Many wine bottles and especially sparkling wine bottles have a more or less large indentation in the bottom (also bottleneck, French Culot de Bouteille). There are several opinions about the practical reasons. Probably the vault comes from the beginnings of production, as the bottles not as today could be made in exactly the same shape and this indentation gave better stability and stability. According to another variant, the vault was created by blowing glass, because the bottle was turned over a wooden stick. The fact is that the arched floor gives better pressure to the walls and ensures that the bottom of the bottle does not break. Also, the argument that one could thereby pack the bottles "Bouteilles stockées sur Pointes" (head to floor) stable, is consistent.
Another advantage is that during the bottle aging Especially with red wines, the precipitates get into the small groove around the indentation. This is the pouring of the depots prevented. With a sufficiently deep indentation, you can use it as a base for the thumb when pouring. Obligatory is the indentation at Bordeaux and champagne bottles but also many Burgundy bottles. Schlegel bottles and carboys, For the manual remuage a sparkling wine is used as a positioning aid for the remnant of many producers at the bottom of the bottle Winery point appropriate.
An interesting story is available at the champagne house Roederer, For the Russian Tsar Alexander II (1818-1881), special champagne bottles were produced for the Cristal brand still produced today. The Krsitall glass had to be transparent in order to be able to quickly recognize any poisoned champagne. In addition, there was no bottleneck to exclude a remnant of a small explosive device in the recess of the bottom of the bottle. The bottles for the Cristal are still produced today.
Image: Norbert Franz Josef Tischelmayer