horizontal circle

horizontal circle

[‚här·ə′zänt·əl ′sər·kəl]
(engineering)
A graduated disk affixed to the base of a transit or theodolite which is used to measure horizontal angles.

horizontal circle

A graduated circle fixed to the lower plate of a transit, by means of which horizontal angles can be measured.
References in periodicals archive ?
Repairing & Servicing of Autolevels (Temporary adjustment (Level screw, tribach plate & trivet plate), Permanent adjustment, Line of collimation, Line of sight, Visibility of cross hair on reticule, Focusing of eyepiece and objective lenses, Removal of parallax, Bubble in spirit level, Horizontal tangent screw, Focusing knob, Removal of zero error in horizontal circle gradation, Compensator mechanism (pendulum prism) etc)
Part of the recording system is a special camera with six separate lenses: five in a horizontal circle and one pointed upwards.