With the invention of the stovetop espresso coffee maker, espresso - long a staple of Italian cafés and bars - became available for home consumption. As the cold water in the lower chamber heats, the pressure from its boiling forces the water up through the coffee grounds. In just a few minutes, espresso emerges from the spout into the upper chamber as the pot hisses and gurgles. Remove the pot from the heat and let it stand until the lower chamber is releasing only steam.The lower water tank holds a metal filter and features a safety valve. The upper tank fills with perfectly brewed coffee. Now Italy"s favorite aluminum coffeemaker can go to work in your kitchen, making delicious espresso on gas or electric stovetops.