8o 



ENGINEERING FOR LAND DRAINAGE. 



The bearing of a line is the angle which it makes 

 with the direction of the magnetic needle. The length 

 of a line with its bearing is termed its course. To 

 take the bearings of a line, set the compass directly 

 over a point in it at one extremity if possible, though 

 this is not essential. Bring the compass to a level 

 position. Have a flag or rod set on another point of 



Fig. i6. — Taking Compass Bearmgs. 



the line. Direct the sights upon this rod as near the 

 bottom as possible. Always keep the north end of 

 the compass ahead. It is distinguished from the 

 south end by some conspicuous mark on the face. 

 Sight accurately to the flag and read the north end of 

 the needle. To do this, note first whether the N. or 

 S. point of the compass is nearest the north end of the 

 needle, second, the number of degrees to which it 

 points, and third, the letter E. or W. nearest the north 

 end of the needle. Always read and record bearings 

 in this order. 



