die 5 but he alwayes found the fame quantity of Declination 
Weft-ward. 
But by the ObfervationSj here made formerly, it appearSjthac 
the Needle hath declin'd Ea/l-mrd to 8 degrees, and hath af- 
terwards been diminifhing, until 'tis come to the other part, 
where wc find it at prefent. The Obfervations, that may be 
made hereafter, will ftiew how far the Declination will advance 
towards the Weftj and what will happen after its greateft elon- 
gation 5 it not being probable, it Ihould encreafe alwayeSj and 
make a whole turn. 
It feems not, that this difference of te^t degrees and more can 
be attributed to the change of the Pole of the Earth, as fome 
efteem'd, perhaps before they knew it was fo great > nor (as 
others would have it) to the Magnet, or to the Iron, that are 
found in certain places, becatife there is but little Load-ftonej 
zxid Mr. Auzout affirms, that the Mines, which he hath feen, 
make no impreffion at all oa the Needle. So that 'tis difficult 
tohitthetrue caufeof fuch a Variation: Yet however, if the 
dire^iion of the Magnet^ and of the Needle touched by it , de- 
pends from the flux of a certain matter , paffing through the 
whole Earth, or the exterior parts of it, ftrait along the Axis% it 
may be faid, that it proceeds from changes made in the faid flux^, 
which^ fuppofing the inequalities of the Earthjand the alterati- 
ons continually mnde therein, as well artificial, by excavations - 
and fuch like other works, as Natural, by corrofions caufed by 
fire and water, or by the generation of Mctta's and Stones ( be-- - 
fides the various changes, wc cannot think of by reafoa of the 
little kno'^'ledgewe have of fo vaft aBody as the Earth ) can- 
not but in progrefs of time change its fcituacion, To illuftrate 
this with an Example taken from Rivers 5 T hey^ akhough they 
were running ftfaic, cannot remain long without winding , and^ : 
changing their courfe, if it happen, that the ground, over which * 
they run^ be unequal, or of a different nature. So 'tis probable^ . 
that the inequ^ilities of the Earth may in time occafion fome 
bending in the current of this Magnetickmaucr, and make it 
change its bed and channel : Whence it comes to pais, that the 
Needle changeth its diredion according as the Current chan- 
geth; whichdreds it. And if you will confider the variety of 
