(t«9 ) 
thereof as can no ways be accounted for by a regular 
Hypothefis* as depending upon the unequal and irregu- 
lar diftribution of the Magnetical matter within the fob- 
ftance of the External (hell or coat of the Earth, which 
defied the Needle from the pofition it would acquire' 
from the effe&of the general Magnetifrnof the whole. 
Of this the Variations at London and Park give a no- 
table inftance, for the Needie has been conftantly a- 
bout i 9 J moreEafterly at Park thm at London 5 thou 
be certain that according to the general effe£t the diffe- 
rence ought to be the contrary way. Notwichftanding 
which the Variations in both places do change alike. * 
Hence, and from lornc other of like nature, I con- 
clude, That the two Poles of the external Globe are 
fixt in the Earth, and that if the Needle were wholly 
governed by them, the Variations thereof would be 
always the fame, with fome little Irregularities upon 
the account I but juft now mentioned ; But the internal 
Sphere having fuch a gradual tranllation of its Poles, 
doesinfluencetheNeedle and direft tt varioufly accord- 
ing' to- the refult of the attra&ive or directive power of 
each Pole 3 and confequently there rnuft be a period 
t>f the Revolution of this internal Ball 9 after which ths 
Variations will return again as before, But if it (hall 
in future ages be obferved other wife, we muft then 
conclude that there are more of thefc Internal Sphere^ 
md more MagneticalPoles than Four, which at prefent 
we have not a fufficient number of Ohfervations to de- 
termine-, and particularly in that vaft Mar del Zu s \ 
which occupies fo great a part of the whole Surface of 
the Earth. 
If then two of the Poles be fixt and two moveable 
it remains to afcertain which they are that keep their 
place: andtho I could with we bad the experience of 
another Century of years to found our .Concltafions up- 
on, yet I thiuk wc may fcfely determine, That cur 
EurogQan 
