text: A direct indicating dial thermometer, common in household devices (such as a patio thermometer or a meat thermometer), uses a bimetallic strip wrapped into a coil in its most common design. The coil changes the linear movement of the metal expansion into a circular movement thanks to the helicoidal shape it draws. One end of the coil is fixed to the housing of the device as a fix point and the other drives an indicating needle inside a circular indicator. A bimetallic strip is also used in a recording thermometer. Breguet's thermometer consists of a tri-metallic helix in order to have a more accurate result.