(E) Try a nail, pen, iron, etc., instead of the needle.
EXPERIMENT 156. To find whether a piece of steel can be permanently magnetized by an electric current.
Apparatus. Same as for last experiment; an unmagnetized sewing-needle; the compass.
394. Directions. (A) Be sure that the needle is not magnetized. It should attract both ends of the compass-needle. How can any magnetism in the needle be removed?
(B) Place the needle inside of the coil with its point to the east; that is, with its point at the N pole of the coil, and its head at the S pole. Close the circuit for an instant. Test the needle again for poles. Is the point a N or a S pole?
(C) Turn the needle end for end in the coil, and see whether its polarity can be reversed.
(D) Experiment with iron wire, nails, steel pens, spring steel, etc.
EXPERIMENT 157. To study the effect of a piece of iron placed inside of a magnetized coil of wire.