66 



UNITED STATES COAST GUARD 



16. MAGNETISM, DEVIATION AND COMPASS COMPENSATION. 



Name and describe the functions of 

 "A," "B," "C" and "D" in the sketch 

 shown. 



Using the Napier diagram shown be- (b) Determine the compass course 



low: to steer to make a magnetic course of 



(a) Determine the magnetic course 260°. 

 when steering 271° by compass. 



At what point in a bar magnet is the 

 attraction greatest? 



If an unmagnetized soft iron bar is 

 brought near a compass, how should it 

 be held to exert the maximum effect? 



What is meant by "dip" (also known 

 as magnetic inclination, or magnetic 

 latitude) ? 



In adjusting the magnetic compass, 



is it best to place fewer magnets very 

 close to the compass or more magnets 

 farther away from the compass? Ex- 

 plain your answer. 



On what magrietic heading of the 

 vessel is the maximum deviation caused 

 by induced magnetism in vertical soft 

 iron? 



