The Abney level is typically used at the eye height of the surveyor, either hand-held or mounted on a staff at that height.
12.
The underside is bright white; on the head the upperside's grey extends town to eye height and the white cheeks may shine up conspicuously, as in the smaller shearwaters of " Puffinus sensu stricto ".
13.
For bicycle facilities, the cyclist's eye height is assumed to be at 1.4 m ( 4.5 ft ), and the object height is 0 inches, since a pavement defect can cause a cyclist to fall or lose control.
14.
Standing in my cockpit ( no real " pit "-- just deck level behind the pilothouse ) my eye height is 3.4 m above the water, which in typical atmospheric conditions gives a ToE 08 : 03, 1 March 2015 ( UTC)
