Suunto Tandem manual Measuring height of a pillar

12m

[38 ft]

48 %

1.6 m 25 ½° [5½ ft]

25 m [82 ft]

Fig. 8. Measuring height of a pillar

10.25m [33½ ft]

13.5m

The task is to measure the height of a pillar at a distance of 25 m [82 ft] on level ground (Fig. 8).

The instrument is tilted so that the hairline is seen against the pillar-top (apex). The reading obtained will be 48 % (ca 25 ½°), As the distance is 25 m [82 ft] the height of the pillar is 48 / 100 x 25 = ca. 12 m [48 / 100 x 82 ft = ca. 39 ft]. To this must be added the eye's height from the ground, e.g., 1.6 m [5 ½ ft]. Their sum is 13.6 m [44 ½ ft], the height of the pillar.

In very exact measurements,

[44½ ft]

3.25 m [10½ ft]

41%

13%

and particularly on sloping ground two readings are taken, one to the top, the other to the base of the pillar. When

25 m [82 ft]

Fig. 9. Taking two readings

the pillar base is below eye level the percentages ob- tained are added. The total height is the sum percentage

13