Percolators began to be developed from the mid-nineteenth century. In the United States, James H. Mason of Massachusetts patented an early percolator design in 1865. An Illinois farmer named Hanson Goodrich is generally credited with patenting the modern percolator. Goodrich's patent was granted on August 16, 1889, and his patent description varies little from the stovetop percolators sold today. With the percolator design, water is heated in a boiling pot with a removable lid, until the heated water is forced through a metal tube into a brew basket containing coffee. The extracted liquid drains from the brew basket, where it drips back into the pot. This process is continually repeated during the brewing cycle until the liquid passing repeatedly through the grounds is sufficiently steeped. A clear sight chamber in the form of a transparent knob on the lid of the percolator enables the user to judge when the coffee has reached the proper color and strength.
A cafetiere (Coffee Plunger, French press in US English) requires coffee of a coarser grind than does a drip brew coffee filter, as finer grounds will seep through the press filter and into the coffee. Coffee is brewed by placing the coffee and water together, stirring it and leaving to brew for a few minutes, then pressing the plunger to trap the coffee grounds at the bottom of the beaker.
Bunn-O-Matic came out with a different drip-brew machine. In this type of coffeemaker, the machine uses a holding tank or boiler pre-filled with water. When the machine is turned on, all of the water in the holding tank is brought to near boiling point (approximately 200–207 °F or 93–97 °C) using a thermostatically-controlled heating element. When water is poured into a top-mounted tray, it descends into a funnel and tube which delivers the cold water to the bottom of the boiler. The less-dense hot water in the boiler is displaced out of the tank and into a tube leading to the spray head, where it drips into a brew basket containing the ground coffee. The pourover, water displacement method of coffeemaking tends to produce brewed coffee at a much faster rate than standard drip designs. Its primary disadvantage is increased electricity consumption in order to preheat the water in the boiler. Additionally, the water displacement method is most efficient when used to brew coffee at the machine's maximum or near-maximum capacity, as typically found in restaurant or office usage. In 1963, Bunn introduced the first automatic coffee brewer, which connected to a waterline for an automatic water feed.
It can take a little while to get to know the ins and outs of a new coffee maker. In CR’s labs, each drip coffee maker we test brews roughly 65 cups by the time our engineers are through with it. And brewing is just one of many aspects we look at. We test for handling and convenience, too, so you can choose a model that helps you sail through morning madness.