Johnson's natural philosophy and key to philosophical charts : illustrated with 500 cuts; being reduced photographic copies of all the diagrams contained in the author's philosophical series of indestructible school charts ; for the use of schools and families (1878)
Fig. 47. … from it a similar polarity, as shown by the letters in the figure; M rep-resenting the magnet, and the other parts of the drawing, small bars-of iron. 336 MAGNETISM. 621. Figure 48.—Magnets do not part with their ownpower.—Magnets do not part with or lose any of their own magneticforce by…
Physics · Astronomy
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