opens within and is adapted to discharge into discharge cavity 50 the rear end 66 of the flight section resides within the auger well motor 70 on the duster drives a speed reducer 76 which drives said auger dust seals 23 are provided referring to fig1 and 7 the access hatch cover 89 is provided with slots 91 into which pivot bolts 93 nest to allow nuts 95 to be tightened down against cover 89 and compress a dust seal 97 an air blower 72 is mounted on either a the duster base frame 12 exterior to the hopper or b on the conveyor frame 87 and has a blower exhaust 74 connected into inlet port 11 by hose 13 or equivalent means this blower preferably is powered by a unique lagged roller system as shown schematically in fig5 and 6 and comprising roller 75 constructed of a steel roller body 77 having a hard rubber covering lagging 79 having ceramic tiles 81 imbedded therein wherein the roller is engaged and driven by the conveyor belt 17 preferably the return run 19 thereof the roller shaft 83 is mounted in bearings e g pillow blocks 85 affixed to the mine conveyor frame.