on Magnetic Attraction . £99 
compass. When the ring is NE. and SW., it will require a 
greater inclination than before of the circle to the north, to 
throw it above the equator ; but an inclination of 55° will have 
this effect when the ring is to the south of the needle, so that 
then the deviation should be all of the south end of the needle 
towards the ring ; and the contrary, when the circle is to the 
north of the compass ; and these likewise correspond exactly 
with Mr Lecount’s observations. 
In the next experiment, with the ring N. and S., it is evident 
that the cc neutral” points ought to be inclined as in the figure, 
and at the extremities of a diameter ; their not being so, most 
probably arose from a slight partial magnetism in the ring, 
which it is extremely difficult to avoid ; or perhaps from the ring 
not being accurately in the meridian, which was likely to be the 
case, as the experiments were made at sea, and it would be al- 
most impossible to keep the ring in the same position exactly, 
with respect to the meridian, during the course of the experi- 
ment. The circle in which we suppose the centre of the ring to 
move being inclined either way, would cause little change in the 
points of intersection with the equator, and consequently in the 
“ neutral” points, as observed by Mr Lecount. 
From what has been said respecting the second and first ex- 
periments, it is evident that the positions of the points in the 
fourth and fifth, as we should determine them, would agree with 
those in the figures. In the fourth experiment, an inclination 
of 60° towards the east would throw the centre of the ring above 
our magnetic equator in the whole of its revolution about the 
compass, when the ring was to the west of the compass, and 
below it when to the east ; so that the south end of the needle 
should always deviate towards the ring in the first case, and the 
north end in the second, as observed. In the fifth, when the 
ring was to the north of the compass, an inclination of £5° or 
30° to the north would throw the circle below the magnetic 
equator, so that the north end of the compass would always de- 
viate towards the ring ; but with all southerly inclinations, the 
circle would always cut the equator ; and when the ring was to 
the south of the compass, and the lower part opposite to it, the 
south end of the needle would still continue to deviate towards 
