82 ELEMENTARY LESSONS ON [CHAP. n. 



of magnetism will therefore be propounded until these 

 facts have been placed before the student. 



LESSON IX. Methods of Making Magnets. 



92. Magnetisation by Single Touch. It has 

 been so far assumed that bars or needles of steel were 

 to be magnetised by simply touching them, or stroking 

 them from end to end with the pole of a permanent magnet 

 of lodestone or steel. In this case the last touched point 

 of the bar will be a pole of opposite kind to that used 

 to touch it ; and a more certain effect is produced if one 

 pole of the magnet be rubbed on one end of the steel 

 needle, and the other pole upon the other end. There 

 are, however, better ways of magnetising a bar or needle. 



93. Magnetisation by Divided Touch. In this 

 method the bar to be magnetised is laid down hori- 

 zontally ; two bar magnets are then placed down upon it, 

 their opposite poles being together. They are then 

 drawn asunder from the middle of the bar towards its 



Fig. 47- 



ends, and back, several times. The bar is then turned 

 over, and the operation repeated, taking care to leave off 

 at the middle (see Fig. 47). The process is more 

 effectual if the ends of the bar are meantime supported 

 on the poles of other bar magnets, the poles being of 

 the same names as those of the two magnets above 

 them used for stroking the steel bar. 



94. Magnetisation by Double Touch. Another 



