Alignment measuring instrument for rail and fitting jig for fixing it to reverence instrument

PURPOSE:To obtain an alignment measuring instrument which can easily make alignment measurement required at the time of installing reference instrument for laying down railway tracks and a fitting jig which can easily fit the alignment measuring instrument to the reference points. CONSTITUTION:A plurality of reference instruments are installed along a proposed railway track laying line and, at the same time, a laser light source 100 is installed to the reference point corresponding to one end of a chord for measuring the alignment of the reference points and a target 200 is installed to the reference point corresponding to the other end of the chord, with chord being constituted of a laser beam 101 emitted from the light source 100. An alignment measuring scale 300 protruding from the reference point is provided in the middle of the chord and, by receiving the laser beam 101 by means of a photoreceptor attached to the alignment measuring scale, an alignment- measured value is obtained.