MAGNETIC CHARACTERS OF METALS, &c. 643 
pure bismuth from some of the impurities with 
which it is frequently contaminated in the mer- 
cantile state. 
19. This purified bismuth having been cast 
into a bar, was afterwards broken into convenient 
fragments and tested by the Torsion Magneto- 
scope, previously described (16), but not the 
slightest trace of magnetism could be detected in 
any of the pieces. 
20. Having satisfied myself that no magnetic 
action resided in the pure bismuth, the dross left 
in the crucible was softened by heat and poured 
on a stone slab, and on being tested developed 
high magnetic powers. It now became obvious 
that the whole of the magnetism displayed by the 
bismuth, when in its first state (17), was due to 
that portion only which was left as dross in the 
crucible after the pure metal had been run out. 
21. From the results thus arrived at I was in- 
duced to fuse other portions of mercantile 
bismuth, and run out the purest portions of the 
metal at the lowest degree of fusible heat, by 
which means I have been enabled to separate 
. the magnetic from the un-magnetic portions, and 
