PURPOSE: To survey correctly and to decrease working time by obtaining the scale (height) obtained by leveling instrument and illumination star and the scale (extension) obtained by a tape measure at once.

CONSTITUTION: A box scale is set so that the scale of the box scale faces a box scale is set a compressed plate 9 of the box scale. Next, a tape measure set pole 26 is set by inserting in a tape measure set pole 15 and then, perfectly inserted in a tension-fixed hole 16. Tape measure is stretched and read the scale 28 by fitting it to the intended standard. At the same time, adjustment is performed by shifting the case of high/low difference measuring instrument and by confirming that bubbles 12 are set horizontally. The scale (height) which agrees with the upper limit of the compressed plate 9 of the box scale is read.