Cory twitter coffee percolator

Back before automatic drip dominated the coffee scene, the most common brewer in kitchens, diners and doughnut wagons was the vacuum percolator. While the vacuum seems like a complicated method, it is actually quite simple, although it’s hard for me to imagine how anyone thought it up.

How does it work?

— The vacuum is a bad name, because the vacuum part doesn’t come unit the end. The idea is this: water is boiled in a lower half. As it reaches boiling, a stemmed upper half is inserted. The steam in the lower half expands and pushes the water up through the tube, through a filter and into the upper bowl.

Vintage CORY DLG Glass "Double Bubble" Vacuum Percolator ...

This upper bowl contains ground coffee. After a minute of contact where the hot water and ground coffee mix together, the lower half is removed from heat. As the lower bowl cools, this causes a vacuum to form and it drags the upper bowl’s freshly brewed coffee through the filter, down the tube and into the lower bowl. When that’s Cory Coffee Makers - eBay DIG