A Bologna bottle, or "Bologna phial", is a glass bottle which has great external strength, often used in physics demonstrations and magic tricks The exterior is generally strong enough that one could pound a nail into a block of wood using the bottle as a hammer, however even a small scratch on the interior would cause it to crumble.
It is created by heating a glass bottle then slowly cooling the outside whilst rapidly cooling the inside. This causes the external strength and internal stress such that even a scratch on the inside is sufficient to shatter the bottle.
The effect is utilized in several magic effects, including the "Devil's Flask".(see link below)
Read more about Bologna Bottle: The Creation of Bologna Bottles, or Bologna Vials As They Were More Commonly Known., Definitions and Related Excerpts From The 19th and 20th Centuries, The Bologna Bottle Today
Famous quotes containing the words bologna and/or bottle:
“I come from a long line of male chauvinists in a very traditional family. To rebel against my background, I didn’t shoot dope—I married a working woman.”
—Joe Bologna (20th century)
“Name me, if you can, a better feeling than the one you get when you’ve half a bottle of Chivas in the bag with a gram of coke up your nose and a teenage lovely pulling off her tube top in the next seat over while you’re doing a hundred miles an hour in a suburban side street.”
—P.J. (Patrick Jake)