
In 1852 it was time to simplify the extraction process with the introduction of the "press filter" or “French press”.
The purpose of these machines is to separate the ground coffee left to soak for a few minutes into boiling water through a filter connected to a piston.
The development over the years involved a search, to ensure a tight seal between the container and the filter.
Combination of a filter and a method of boiling with boxed filter: manufacturer unknown, France, about 1850