viz.— Signals, bandrols, or jalons, common staves, picket posts, rods, measuring chains, measuring cord, the step.
b. Instruments used for protracting the lines measured, viz.—
The step measure, calliper compasses, beam compasses, dividing and reducing compasses.
c. Instruments for measuring and marking out horizontal angles: The
square, the plane table, caloptric compasses, the reflector, the sea-compass, the prismatic compass, the astrolabe:
d. Instruments for measuring vertical angles:
Lehmann’s dioptric rule, Schmalkalder’s holometer, the quadrant.
e. Leveling instruments:
The ordinary mason’s level, the spirit level, the water level, the spirit level à lunette, the plumb rule, Lehmann’s dioptric rule in connection with the plane table, placed horizontally, the surveyor’s rule, Schmalkalder’s holometer.
2. Operations in surveying with the plane table, astrolabe, reflector, and compass.