Abstract: An improved system and method for gravimetrically feeding material at a controlled rate. The material to be fed, which can be either a dry solid or a liquid, is maintained in a supply vessel. A probe disposed in the supply vessel detects the level of the material, sending a high level signal to a controller. A scale weighs the material in the supply vessel, sending a weight signal to the controller. The controller then calculates the density of the material in the supply vessel based on the weight and density of the material. The calculated density is used to affect the feed rate to achieve an operator-input set rate. During refill of the supply vessel, the probe detects material at a high level, sending a signal to the controller which, in turn, sends a signal to a refill valve, stopping refill.