Abstract: A filing tool (1) for filing one or more sheets 6 provided with a magnetically attractable area (7) on a side end or periphery of the sheet is composed of a two-folded cover member (2) having a back (2a), an electromagnet (3) situated along the back (2a), an and an ON-OFF switch (5) for changing "ON" to "OFF" or "OFF" to "ON" for flowing a current to the electromagnet (3). Thereby, the sheet can be readily attracted by the cover member and can be readily detached therefrom by operating the ON-OFF switch. Further, even an intermediate sheet can be easily picked up.

Abstract: A landing apparatus for an airship or the like is composed of a windlass 2, 3 mounted on the lower part of said airship 1, a tugging hawser 4, 5 releasably wound in said windlass 2, 3, a mooring device 6, 7 connected to a leading end of said hawser 4, 5 and a lashing rope 9, 10 horizontally extended spaced relation from a landing space 8. The airship can be landed by its own power when the hawser 4, 5 hanging from the airship is engaged with the lashing rope 9, 10, and is wound by the windlass 2, 3. The airship can be landed on a narrow landing space 8 since the airship is not blown off by the wind.

Abstract: A scale usable as a life line includes a metal wire 5 of high tensile strength with graduation 6 in a longitudinal direction thereof, a drum 2 for winding the metal wire 5 thereonto, a casing 1 accommodating the drum 2 while permitting the same to rotate, and a magnifying glass 7 for allowing the graduation 6 to be read, wherein the metal wire 5 of high tensile strength is formed of a strand comprised of a plurality of steel wires of a fine grained composition each having a diameter of 10 to 100 .mu.m and a coat of a synthetic resin covering the strand.