Abstract: The closed long bag enclosed a little air is connected to the preliminary line for inserting cable into the conduit by the small suction pump. The shape of closed long bag enclosed a little air can be changed easily. As the result, the closed long bag moves through a narrow portion and a bending portion of the conduit smoothly. Furthermore, air in a tail portion of the closed long bag moves to a head portion of the closed long bag by difference between the front portion and the end portion of the closed long bag. The head portion of the bag expands and the tail portion of the bag shrinks. As the result, the bag pulls the line very strongly.

Abstract: A line member inserted into a inlet port of the conduit comprises a thin nylon tape. The tape comprising the line member flies into the conduit with the fluid mechanical force in the air stream.