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instruments also include instruments for astronomical determinations
associated with geodetic projects, as well as for surveying.
Instruments and devices for measuring the length of lines include
steel measuring tapes, invar tapes, rangefinders, which are either

combined with a telescope or are attachments for the telescope of a
geodetic instrument.
Instruments for determining directions and measuring angles. A

prototype of these instruments was the astrolabe, from which angles
were measured with the aid of a rotating rule with diopters for sighting
at an object. Other angle-measuring instruments, such as the
pantometer (an astrolabe with a vertical circle, permitting the

measurement of horizontal as well as vertical angles), In the 17th
century telescopes, microscopes, verniers, levels, and crosshairs began
to be used in goniometric instruments. The basic angle-measuring

instrument, which was called the theodolite, was formed in this way.
Instruments for determining superelevations. Mechanical-optical
levels with horizontal collimating rays are usually used for leveling.

Instruments for graphic surveying. In spite of the large-scale
development of stereo-photogrammetric surveying methods, graphic
or plane-table surveying is still being used. The basic instruments for

this technique are the plane table and the telescopic alidade.
Over the years, a number of various instruments have been
invented for measuring distance, direction, vertical and horizontal
positions, time and astronomical location. Many have been overtaken

by technology which has replaced several different instruments with
all-in-one total solutions.

Task 2. Put up 5 general and 5 special questions to the text.

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