BappIcKeR—On the Influence of Magnetism on the Rate of a Chronometer. 15 
near approach of anything magnetical) on ship-board.” And further, he thinks it 
probable that the balance-spring will be similarly affected, ‘since it is well known 
that chronometers having gold balance-springs, although more difficult to adjust, 
yet keep better rates at sea than the others.” 
Fisher’s experiments are very defective in point of accuracy. There is, for 
instance, neither an account of the temperature, nor are the detached rates of the 
chronometers given—so that it is impossible to discuss the results thoroughly. It 
is, however, probable that a magnet at such a short distance will obscure all other 
disturbing influences; nevertheless I do not think that Fisher’s conclusion in favour 
of acceleration with magnetic action deserves much confidence, as the number of 
experiments is too limited, and as so strong a magnetism must necessarily have too 
strong an effect upon the whole work of a chronometer as to admit of any general 
deduction. One fact is, however, remarkable, and not the less so for the preceding 
notes, viz., that the effects of north and south poles upon No. 8 are nearly opposite 
each other, while they are very nearly the same in No. 4. This seems to involve 
that No. 3 had already, before the experiments began, acquired polarity, though it 
is difficult to say which of the steel parts had become magnetic. It is only made 
probable by Fisher’s remark about the effect of the magnet when out of the plane 
of the balance, that the balance is the chief part acted upon; and it is to be re- 
eretted that these latter observations have not been reproduced in full. As 
Fisher’s experiments stand, they are to be considered as preliminary ones only. 
I may, perhaps, finish these remarks about Fisher’s observations by quoting a 
criticism of them by Barlow out of his Paper (No. 6), which will occupy us presently, 
and which is very much to the same effect as ours. He says: ‘The experiments 
and observations which Mr. Fisher describes as having been made with a strong 
bar magnet, brought within two inches of the balance, I consider to be perfectly 
distinct in their nature from those which were made by him on board and on shore 
at Spitzbergen; for a magnet of such power, brought within the distance of two 
inches of any small piece of steel, will, whether the latter be previously magnetic 
or not; impress upon it a strong temporary derangement of its latent magnetism, 
and give to the part nearest to the magnet a contrary pole to that by which it is 
opposed ; and consequently there will exist between the balance and the magnet a 
strong power of attraction, sufficient to cause that acceleration so strongly indicated 
in Mr. Fisher’s experiments; and this will be the case whichever end of the magnet 
is opposed to the balance and to whatever part of the latter the application is made ; 
because, in this instance, the effect does not depend upon the previous magnetic 
state of the balance, but upon that temporary state excited by the proximity of 
the magnetic bar, and which ceases when the bar is removed.” 
