In stove top or table top versions, the glass globed vacuum pot produces a full-flavored brew. Two stacked glass bowls are connected by a the upper globe's tube. Coarsely ground coffee is put in the top globe and cold water in the bottom. As the water heats, it is forced into the top chamber by the steam pressure, where it mixes with the coffee. The pot is removed from the heat and within a few minutes the liquid falls into the lower pot, leaving the grounds behind.
Boiling water is pumped through a tube, where it mixes with ground coffee.
As the coffee brews, it repeatedly passes through the grounds. It is a lesser preferred method of brewing as it tends to bring out coffee's bitterness and acidity. Also known as the French press, this 1920's glass and metal design steeps loose ground coffee in hot water. A brewing method available in stove top and countertop versions. Both machines operate on the same principle where hot pressurized water is forced through a filter holding finely ground coffee.