A coffee percolator is a type of pot used for the brewing of coffee by continually cycling the boiling or nearly boiling brew through the grounds using gravity until the required strength is reached. Coffee percolators once enjoyed great popularity but were supplanted in the early 1970s by automatic drip coffee makers. Percolators often expose the grounds to higher temperatures than other brewing methods, and may recirculate already brewed coffee through the beans. As a result, coffee brewed with a percolator is particularly susceptible to over-extraction. However, percolator enthusiasts maintain that the potential pitfalls of this brewing method can be eliminated by careful control of the brewing process.