backsight method

backsight method

[′bak‚sīt ′meth·əd]
(engineering)
A plane-table traversing method in which the table orientation produces the alignment of the alidade on an established map line, the table being rotated until the line of sight is coincident with the corresponding ground line.
Sighting two pieces of equipment directly at each other in order to orient and synchronize one with the other in azimuth and elevation.