An Improved Measuring Instrument for the Solution of Triangles and other Trigonometrical Operations in Surveying and the like.

摘要

23,275. Fregoso, T. Oct. 24. Calculating-apparatus. - An instrument for solving right-angled and other triangles in connection with surveying and the like has a rectangular frame A with graduations B, B', a fixed quadrant C, and an adjustable protractor G. The quadrant and protractor have each two scales with verniers which are carried by two graduated rules D, H, turning on pivots at the centres of curvature of the circular scales. Each rule carries a clamping- screw D2, H2 and a vernier. The protractor G may be adjusted by a rack and pinion. In determining the departure and latitude nr rectangular coordinates from a distance and bearing, the rule H is placed at right-angles to the scale B.