0 a piece of string with a weight attached to one end, used either to test if something vertical, such as a wall, is exactly straight, or to find the depth of water
The angle of inclination relative to the horizontal of the petiole, lamina and drip tip of each leaf was measured using a transparent plastic protractor and a plumb line.
It involved the use of a bar with a plumb line, attached to a wooden handle.
It is derived by deducting normal heights from the normal plumb line.
A section of the scaffolding would hold a plumb line that was centered over a datum mark on the floor.
Apparently if a plumb line is dropped from the north side of the tower it would fall 3 feet away from the building.
It even gave instructions on how to obtain measurements using the plumb line.
The outer casing of the gyrocompass device is held in such a way that it remains aligned with the local plumb line.
A plumb line dropped from the tower revealed that the concrete block had settled during the storm, giving the lighthouse a pronounced shoreward list.