6" Black Gunmetal Finish Surveying Geologist Alidade with a Telescope & Compass
This alidade made of solid brass with an antique black gunmetal coating.
Weigh 750gms when packed and is 5.5" in height.
The telescope is covered in leather and extends to 6".
There is a small level above the telescope.
Diameter of the working compass below the arc is 3". and base is 3,5"
There are 3 levelling screws & a mechanism to lock the compass during transport.
This piece would make an excellent unusual gift for surveyor, astrologer or person interested in scientific readings.
Please not this is a decorative item & not calibrated for precision readings.
An alidade (/ˈæ.lɪ.deɪd/) (archaic forms include alhidade, alhidad, alidad) or a turning board is a device that allows one to sight a distant object and use the line of sight to perform a task. This task can be, for example, to draw a line on a plane table in the direction of the object or to measure the angle to the object from some reference point. Angles measured can be horizontal, vertical or in any chosen plane.
The alidade was originally a part of many types of scientific and astronomical instrument. At one time, some alidades, particularly using circular graduations as on astrolabes, were also called diopters. With modern technology, the name is applied to complete instruments such as the plane table alidade.