Mr Christie’s Observations 
m 
centre of the ring passes below the magnetic equator, it then 
acts most strongly on the northern branch of our column of 
magnetic particles, and, in consequence, the north end of the 
needle ought to deviate towards the ring ; and this should con- 
tinue until the centre of the ring again intersects the equator. 
The centre of the ring now rising above the equator^ the ring 
will act most strongly on the southern branch of our column, 
and, in consequence, the south end of the horizontal needle 
would deviate towards the ring during the remainder of the re- 
volution. From this it is evident, that the points opposite to 
which the compass is, when the centre of the ring is in the mag- 
netic equator of the needle, will divide the ring unequally. 
The upper, or that opposite to which the compass is when the 
north end of the needle deviates, being the smaller portion ; so that 
the less portion of the ring at the top would appear, according to 
Mr Lecount’s expression, to possess 64 north polarity,” and the 
greater, at the bottom, 44 south polarity.” The phenomena, when 
the ring is to the north of the compass, would take place in a 
similar manner, but in a reverse order. While the small circle, 
in which the centre of the ring moves, is inclined southerly to- 
wards a horizontal position, the only change that would, accord- 
ing to our hypothesis, take place in the 44 neutral” points in the 
ring, is, that they would more nearly bisect it ; but when the 
circle is inclined northerly, at an angle of 45°, the centre of the 
ring, when it is to the south of the compass, would always be 
above the equator, so that the south end of the needle ought 
always to deviate towards it, though but slightly, when opposite 
the upper part of the ring : the reverse ought to take place 
when the ring is to the north of the compass ; all these are pre- 
cisely the effects observed by Mr Lecount, as stated above. 
Let us now see what effect we should expect when the ring 
is vertical, and has a NE. and SW. direction. Here the 
small circle is still divided unequally by the equator ; but the 
point of division on one side will be considerably higher than on 
the other, and when the ring is to the south of the needle, rea- 
soning as in the last case, the point separating the northern from 
the southern deviation will be higher on the eastern, or in the 
figure the left hand side, than on the western. The contrary 
of this ought to take place, when the ring is to the north of the 
