Replies

In the case of beer, it isn't the volume of the glass, but rather the shape that determines how much is liquid and how much is foam. For example, a wide schooner has a much greater head and less beer, while a narrow pilsner has less head and more beer. The difference is so great that when I showed a restaurant owner the yield per keg of various glasses he immediately called his glass vendor and ordered new glasses. He figured he could pay for the conversion in a few days.

As an aside, a jigger - shot - is supposed to be 1.5 ounces. You can get the line anywhere you want, but it is usual to be at an ounce. As a further aside, I knew a bartender that liked to play elf tricks on his customers. He had a jeweler drill a few tiny holes just at the top of the line on some shot glasses. Sitting at the bar, the holes were undetectable but standing they were obvious. He would present a shot with the holes so that as the glass was tipped a few drops would end up on the drinker's chin. Good fun for all.