A portable surveying instrument, originally for measuring horizontal angles, and consisting essentially of a planisphere or horizontal graduated…

the name given by Digges to a combined surveying instrument, such as is now called a theodolite, n.

= plane table, n.

Surveying. An instrument consisting of a flat brass bar with sights at the ends and a circular brass box in the middle, containing a magnetic…

An ancient form of theodolite, or instrument for taking angles.

A portable instrument consisting essentially of a board or small table that has an alidade or sighting rule on it and can be levelled and can hold a…

= circumferentor, n. 1.

A mathematical instrument, used for measuring angles in surveying; otherwise called a semi-circle. †Also, a goniometer used in crystallography.

A semicircular instrument or one marked with a semicircle; now only = graphometer, n.

a theodolite equipped with a short telescope that is capable of rotating through 360 degrees vertically.

= diopter, n. 1.

= circumferentor, n. 1. Obsolete. rare.

a goniometer with horizontal and vertical graduated circles.

a type of theodolite incorporating a gyroscope as an aid to orientation.