United States contractors engaged in doing similar work will be interested in a continuous slip-forming rig which Australian engineers have developed for lining irrigation channels. Named from the front of the unit backwards, the slip-form is made up of a skid pad, a partitioned hopper, a vibrating pad and a float pad and pressure blade. Initial earthworks involved the construction of the compacted banks and the completion of all lead by excavating with a dozer and scoop to a depth determined by the scoop width. This was followed by the excavation of the remaining section of channel and trimming of the cannel section by a Briscoe ditcher towed by two tractors. Later the spoil was spread evenly over the banks on either side. The slip-form is advanced by means of a winch mounted on an anchoring device which automatically digs into the ground when the pull is applied. About 300 feet of travel is possible before the anchor must be shifted.