36 A MANUAL FOR NORTHERN WOODSMEN 



been run out and the latitude and departure computed, as 

 given. The result shows that the point reached is north 



FIGURED LATITUDES AND DEPARTURES 



X 



and east of the starting point, much further north than 

 east; hence a course somewhat west of south 

 E must be set to reach it. In the figure E X 

 represents the latitude reached and A X the 

 departure. 



Now to find the bearing of E A we have 



"'-H-S-- > 



A E X from the table of tangents = 18 50'. 

 S 18 50' W is therefore the bearing required. 

 S The length of E A may also be found, since 

 it is the hypothenuse of a right angled tri- 

 angle whose base and altitude are the latitude and de- 

 parture given. 



V21.022-f7.17 2 = 22.21, 



the distance required. That this value and that for the 

 angle differ somewhat from the true ones is due to the 

 errors of compass surveying. 



In a similar way the course and distance of an inacces- 

 sible line may be computed or omissions supplied in notes. 



