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measurement wheels that work like protractors for reading horizontal
and vertical angles, and bubble levels to ensure that the angles are
true.

Figure 10.8. Measuring angles

VI. INDIVIDUAL WORK

Task 1. Complete the text with the words from the box and
translate it into Ukrainian.

on the tripod; station point; measuring angles;
adjusting; leveled; optical theodolites;

mounted to; electronic theodolites;

Theodolites

Theodolites are precision instruments for ________ in the
horizontal and vertical planes. It is a basic of unknown origin but
going back to the 16th-century English mathematician Leonard

Digges; it is used to measure horizontal and vertical angles. In its
modern form it consists of a telescope,______ swivel both horizontally
and vertically. Leveling is accomplished with the aid of a spirit level;
crosshairs in the telescope permit accurate alignment with the object

sighted. After the telescope is adjusted precisely, the two
accompanying scales, vertical and horizontal, are read. Mounted on a
tripod with adjustable legs, the theodolite is used in the field to obtain

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