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Magnetism. 



Magnets. 



For lessons on magnets an ordinary horse-shoe magnet, such as 

 any boy may carry in his pocket, will answer. It is well also to 

 have a bar magnet. 



Provide some small articles of soft iron and of steel. Ordinary 

 knitting needles or sewing needles will do for steel. Try the soft iron 

 first. It will readily be drawn to the magnet. While it is still 

 attached, put the free end of the soft iron into iron-filings. Then 

 withdraw the magnet. What happens? Try the same with a piece of 

 steel. If you have pure soft iron, it will be found that it remains a 

 magnet only when in contact with a magnet, but that steel 

 retains its magnetism for some time. Let the children find what 

 things are attracted by the magnet, what not. 



Sewing needles may be magnetized by drawing one pole of 

 the magnet several times across them, drawing the magnet only 

 one way. A needle is conveniently suspended by being thrust thru 

 a cardboard triangle, and the triangle suspended from one of its 

 points. Note in what position the needles come to rest. Suspend two 

 needles near together and bring two south poles together. What 

 happens? Bring two north poles together. What happens? A 

 north and a south? The facts of attraction and repulsion may be 

 shown as well by using one needle and a magnet, but care must be 

 taken that the magnet does not come into contact with the needle, 

 or the poles of the needle may be reversed. For reason see some text- 

 book on Physics. The compass may now be brought in and the class 

 will be able to see that it acts in the same way as their suspended 

 needles. It may be interesting to children to know that the earth 

 acts as a huge magnet, but that its magnetic poles do not correspond 

 with its geographical poles. The magnetic needle does not point 

 to the true geographical north, but to the east or west of it. At 



