Abstract: An envelope feeder has a movable weight with a relatively large surface area adjacent one of two substantially parallel side walls of the envelope feeder. The weight has gears on opposite ends of a rotatably mounted shaft on which the weight is pivotally supported. The gears cooperate with racks in the two side walls to allow up and down motion of the weight while the shaft stays parallel to the floor. Thus, the position of the movable weight is never skewed. The side wall, which is remote from the relatively large surface area of the movable weight, has a limiter extending therefrom towards the other wall. The limiter acts only on envelopes exceeding a predetermined width to limit the height of a stack of such envelopes so that the power of the envelope advancing motor for feeding each envelope from the bottom of the stack is not exceeded.