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4.3 Taping Equipments and Methods
Measuring horizontal distances with a tape is simple in theory, but in actual
practice, it is not as easy as it appears at first glance. It takes skill and experience
for a surveyor to be able to tape a distance with a relative accuracy between 1:3000
and 1:5000, which is generally acceptable range for most preliminary surveys.

4.3.1 Tapes and Accessories
Most of the original surveys were done using Gunter’s chain for measurement
of horizontal distances. To this day, the term chaining is frequently used to
describe the taping operation. While the Gunter’s chain itself is no longer actually
used, steel tapes graduated in units of chains and links are still available.

Steel Tapes
Modern steel tapes are available in variety of lengths and cross sections; among
the most commonly used are the 100ft-tape and the 30-m tape, which are ¼ in and
6mm wide, respectively. Both lighter as well as heavier duty tapes are also
available.

Fig. 4.3. Fiberglass tapes (a) Closed case; (b) Open reel
4.3.2. Accessories for Taping
Accurate taping cannot be done with the tape alone. When taping horizontal
distances, the tape very often must be held above the ground at one or both ends.
One of the most important accessories for proper horizontal taping is the plumb
bob. It is a small metal weight with a sharp, replaceable point. Freely suspended
from a chord, the plumb bob is used to project the horizontal position of a point on
the ground up to the tape, or vice versa.

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