Bull's eye level
Encyclopedia
A bull's eye level is a type of spirit level
that allows for the leveling of planes in two dimensions - both the 'pitch' and 'roll' in nautical terms. Standard tubular levels only consider one dimension. Bull's eye levels are used primarily by carpenter
s in construction, but can also be found as features of compass
es or other devices that need to be kept from tipping in certain directions (whether it be for functionality or precision of measurements). Small bull's eye levels are also found incorporated into tripods
.
Another name for a bull's eye level is a "circular bubble" which is the name used by surveyors in the United Kingdom. Surveying instruments such as theodolite
s (transits) and total station
s often have a circular bubble as well as a tubular level or "plate level". The circular bubble is used to roughly level the instrument in two dimensions and then the plate level, being more precise, is used to level the instrument more precisely in each dimension separately by leveling the plate level, then spinning the instrument 90 degrees and leveling the plate level again.
Spirit level
A spirit level or bubble level is an instrument designed to indicate whether a surface ishorizontal or vertical . Different types of spirit levels may be used by carpenters, stonemasons, bricklayers, other building trades workers, surveyors, millwrights and other metalworkers, and in some...
that allows for the leveling of planes in two dimensions - both the 'pitch' and 'roll' in nautical terms. Standard tubular levels only consider one dimension. Bull's eye levels are used primarily by carpenter
Carpenter
A carpenter is a skilled craftsperson who works with timber to construct, install and maintain buildings, furniture, and other objects. The work, known as carpentry, may involve manual labor and work outdoors....
s in construction, but can also be found as features of compass
Compass
A compass is a navigational instrument that shows directions in a frame of reference that is stationary relative to the surface of the earth. The frame of reference defines the four cardinal directions – north, south, east, and west. Intermediate directions are also defined...
es or other devices that need to be kept from tipping in certain directions (whether it be for functionality or precision of measurements). Small bull's eye levels are also found incorporated into tripods
Tripod (photography)
In photography, a tripod is used to stabilize and elevate a camera, or to support flashes or other photographic equipment. All photographic tripods have three legs and a mounting head to couple with a camera...
.
Another name for a bull's eye level is a "circular bubble" which is the name used by surveyors in the United Kingdom. Surveying instruments such as theodolite
Theodolite
A theodolite is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are mainly used for surveying applications, and have been adapted for specialized purposes in fields like metrology and rocket launch technology...
s (transits) and total station
Total station
A total station is an electronic/optical instrument used in modern surveying. The total station is an electronic theodolite integrated with an electronic distance meter to read slope distances from the instrument to a particular point....
s often have a circular bubble as well as a tubular level or "plate level". The circular bubble is used to roughly level the instrument in two dimensions and then the plate level, being more precise, is used to level the instrument more precisely in each dimension separately by leveling the plate level, then spinning the instrument 90 degrees and leveling the plate level again.