The splitting of the granite was done by a method known as feather and tare, which had replaced the former 'wedge and groove' method around 1800; this more reliable method being another reason why the use of granite had become practicable. The new method worked by means of a series of holes was made along a potential line of fracture using a tool called a 'jumper'. "Feathers" were metal prongs with a curved upper end. Two of these were inserted into the holes, the curves in opposite directions at 90 degrees to the line of potential fracture. A wedge-shaped metal "tare" was hammered between the two until the granite fractured.