The quadrants of geographical location are found on the ocean and land through astronomical survey to measure the coastal navigation and topographic work of horizontal angle.

摘要

Quadrant to find geographic situations at sea and earth for astronomical means for measuring horizontal angles in coastal navigation and surveying work characterized by being constituted by an arc quarter circle secured at one end to a base surface perpendicular to the plane of said arch on the contrary to a radius which in turn is secured to said base at its opposite end being provided a rotating radius on its axis and provided with a clamp which embraces the arc which acts as a guide in the pivoting movement of said radius exist in such clasping an index pointing on a graduation marked on the bow nonius.