Davis's manual of magnetism : including galvanism, magnetism, electro-magnetism, electro-dynamics, magneto-electricity, and thermo-electricity (1854)
Davis, Daniel · Boston : Palmer and Hall · leaf 242
edle willswing round, and itssouth pole be drawn tothe bar, as indicated bythe dotted lines in thecut. The polarity thusinduced is not reversedby merely inverting therod, but the aid of per-cussion will be required, in order to remove or reversethe magnetism. This is especially the case when asteel… … ?26 DAVISS MANUAL.. to turn itself north and south, when balanced on apivotj as shown in Fig. 158. The end which was Fig, 158.
