on an upper area of the delivery chute 15 as shown the delivery chute 15 having the form of a short tube of generally rectangular cross section encloses substantially the full area of the upper face of the lower housing section 11 within the respective housing flange 18 the chute 15 is inclined upwardly and forwardly from the lower housing section 11 towards the loading section 14 on a rearward inclined face 42 of the chute 15 there is an inlet vent in the form of an aperture 41 cut into this chute face and a cylindrical tube 43 welded to the face as indicated the center of the inlet vent 43 is disposed rearwardly to the right in fig3 of an imaginary vertical plane passing through the axis of rotation of the agitator shaft 28 the upper end of the chute 15 has a rectangular opening or entrance 44 the opening 44 is closed by a gate or door 46 in the form of a flexible panel of elastomeric material the gate 46 is secured by screws or the like along its upper horizontal edge to the adjacent area of the chute 15 and operates in the manner of a living hinge allowing it to swing inwardly to admit material into the chute the open position of the gate 46 is indicated in phantom at 47 the loading station 14 is integrally formed as by welding with the delivery chute 15 and includes a generally horizontal loading platform 51 and opposed vertical panels 52 at each side of the platform serving to support the platform and guide material into the chute the housing sections 11 and 13 and legs 21 are dimensioned to support the platform.