26 INSTRUCTIONS FOR MAKING FOREST SURVEYS, ETC. 



location. Suppose that (7, D, and E were located by 

 the third method and are high and well-defined peaks. 

 They form a triangle which can be accurately platted 

 on the paper, and the best plan is to prick in the points 

 with a fine needle. The surveyor will then proceed 



FIG. 7. Plane-table method of locating points on both sides of a base line which are 

 to be occupied later and the survey extended. 



by setting up the table at the point which is to be 

 located and from which he can see the three peaks. 

 Orient approximately by compass. With the alidade 

 draw lines from each peak toward the point of set-up. 

 If the three lines intersect, the desired point is located, 



