A method and apparatus of supplying material from a storage hopper (12) to a weighing hopper (16) where the material is fed at a controllable rate by a sliding plate member (104) that acts as a shutter for the storage hopper (12), which includes an aperture (154) for receiving material gravity fed from the storage hopper (12). As the plate (104) is reciprocated horizontally at a preselected frequency, material is conveyed at a controlled rate from the storage hopper (12) to the weighing hopper (16).