ELECTEOD YN AMIC QUALITIES OF METALS. 
711 
of magnetism by weights on and increase by weights off, when the magnetizing current 
was flowing. But when the current was stopped large effects (larger than those when 
the current was flowing) were produced by putting on and taking off the weights ; and 
these effects were always of the same kind, whichever had been the direction of the 
current. 
195. I have not yet been able to explain these effects by terrestrial magnetic force*, 
nor to even guess any other possible cause ; and have in fact, since the 23rd of December 
last, been exceedingly perplexed by seeming anomalies which the various soft-iron wires 
tried have presented, commencing that day with a reversal of the electromagnetic effect 
of the “ off” and “ on” which the first of the wires experimented on showed after the 
magnetizing current had been made for the first time and broken, and a weight of 14 lbs. 
put on and off several times had first shaken out nearly one third of the residual mag- 
netism, and then given alternate augmentation by “ on ” and diminution by “ off” of the 
magnetism that remained. A weight of 28 lbs. was then hung on, and it stretched the 
wire permanently by about 8 per cent, of its length. Then immediately I found reverse 
effects by putting off and on and off the 28 lbs., and on and off smaller weights — the 
“on” giving diminution and the “off” augmentation of what would have been the 
residual magnetism, if residual magnetism there was, from the first magnetization by 
the current. This quality remained until an hour or two later, when the current was 
once more made in the same direction as the first, and broken again. Then 14 lbs. put 
on actually gave augmentation of the residual magnetism (instead of shaking out a con- 
siderable quantity as the first “on” after the first “B” had done), and the offs, ons, 
and offs following gave alternate diminution (by the offs) and augmentation (by the ons) ; 
that is to say, the effects were the same in kind as the effects which had been observed 
before the stretching by the 28 lbs. ; but they were nearly three times as great in amount 
as they had been then, with the same weight of 14 lbs. on and off. Thenceforth the 
same piece of wire (experimented on several more days up till Jan. 12, 1875) and other 
pieces of similar wire tried after it, with the current made sometimes in one direction 
and sometimes in the other, and broken, and different amounts of weight up to 28 lbs. 
put on and off, always showed increase of the residual magnetism by the “on” and 
diminution by the “ off.” Even the first “ on ” after the stoppage of the current gave 
always an increase of the magnetism; but when the weight was as much as 28 lbs. the 
“ shaking out ” tendency was remarkably shown by the increase by the first “ on ” being 
much less than the diminution by the first “off.” 
196. The soft-iron wire experimented on on the 2Srd of December gave, with 28 lbs. 
hanging on it, smaller effects of successive “ makes,” in one direction, and breaks of the 
current ; a greater effect when it was made in the reverse direction ; and a smaller sum 
* [Note added January 1877. — Nearly six months later I ascertained that these startlingly great effects 
actually were due to the vertical component of the earth’s force, though this was only about -J-jj of the magne- 
tizing force of the currents used.] 
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