A vacuum coffee maker brews coffee using two chambers where vapor pressure and vacuum produce coffee which is clean, crisp, rich and smooth compared to other brewing methods. This type of coffee maker is also known as vac pot, siphon or syphon coffee maker and was invented by Loeff of Berlin in the 1830s. These devices have since been used for more than a century in many parts of the world. Design and composition of the vacuum coffee maker varies. The chamber material is pyrex, metal or plastic, and the filter can either be a glass rod, or a screen from cloth, paper or nylon. The Napier Vacuum Machine, presented in 1840, was an early example of this technique. While vacuum coffee makers generally were excessively complex for everyday use, they were prized for producing a clear brew, and were quite popular until the middle of the twentieth century. The Bauhaus interpretation of this device can be seen in Gerhard Marcks’ Sintrax coffee maker of 1925.
An early variation of this principle is called a balance siphon. This implementation has the two chambers arranged side by side on a balance-like device, with a counterweight attached to the heated chamber. Once the vapor has forced the hot water out, the counterweight activates a spring-loaded snuffer which smothers the flame and allows the initial chamber to cool down thus creating a vacuum and causing the brewed coffee to seep in.