ANGULAR SURVEYING 



55 



longitudes of P, Q, Pi, and Q\ are, respectively, H'P, K'Q, 

 Hi' Pi, and Ki'QiJ they are positive. The longitudes of Pz and 

 Q-i are, respectively, # 2 'P2 and Ki'Qr, they are negative. If 

 the line is run from P to Q, the latitude range of PQ is KQ 

 HP = PD, and is positive. Similarly, the longitude range of 

 PQ is equal to K'Q - H'P = DQ. If run from Q to P, its latitude 

 range would be HPKQ=EQ=PD, and its longitude 

 range H'P - K'Q = EP=- DQ, The latitude range indicates 

 how far the end of the line is north or south of the begin- 



ning; and the longitude range, how far the end of the line is 

 east or west of the beginning, or of the meridian passing 

 through the beginning. The latitude range is positive and is 

 called a north latitude range, or a northing, whenever the line 

 bears north; it is negative, and called a south latitude range, 

 or a southing, whenever the line bears south. The longitude 

 range is positive, and is called an east longitude range, or an 

 easting, when the line bears east; it is negative, and called a 

 west longitude range, or a -westing, when the line bears west. 



