A coal cutter that cuts a groove in the coal by an endless chain traveling around a flat plate called a jib. The chain consists of a number of pick boxes. Each box holds a cutter pick fastened into the box by a set screw or similar device. The coal cutter pulls itself along the face by means of a rope at a speed ranging from 7 in/min (17.8 cm/min) to 5 ft/min (1.5 m/min) or more. The chain travels around the jib at a speed ranging from 320 to 650 ft/min (97.6 to 198.2 m/min). The cut in the coal ranges from 3-1/2 to 7-1/2 in (8.9 to 19.1 cm) high and up to 8-1/2 ft (2.59 m) in length.