C aid ; 
"^^opem North-Pole its Meridian being little removed from 
thofe of ihefe places ; and of it felf requiring the fame Va- 
riations we here find. After the fame manner we might 
proceed to conclude the Variations in other places under 
and near the Equator ; but I purpolely teave it for an ex- 
ercife to the thoughts of the Serious Reader, whoisdefi- 
red to help his imagination, by having before him a Map 
or Globe of the Earth ; and to mark thereon the Magneti- 
cal Poles in the Longitudes and Latitudes I afiign the m. 
Thus I hope I have not loft my Pains and "Study in this 
difficult Subjed ; believing that I have put it paft doubt , 
That there are in the Earth Four fuch Magnetial Toints 
w Poles which occajion the great variety and feeming irregularity 
which is obferved in the variations of the Compafs. But to cal- 
culate exa(JHy what it is, in any place affigned, is what I 
dare not yet pretend to i the I could wi(h it were my hap- 
pinefs to be able to oblige the world with fo ufefuU a peice 
of knowledge, there are difficulties that occur that render 
the thing as yet not feafible, forfirft there area great ma- 
ny obfervations requifite, which ought to be made at the 
fame time 5 not at Sea ^ but alliore ; with greater care and 
attention than the generality of Saylors apply. And beGdes 
it remains undetermined in what proportiom the attraftive 
power decreafes , as you remove from the Pole of a Mag- 
net h without which it were a vain attempt to go about to 
calculate. There is yet a further difficultie , which is the 
change of tfiie variation, one of the difcoveries of ihis 
Jaft Century J which fhews/that it .will require fome 
Hundreds of years tpeftablilh acompleat doctrine of the 
Magnetical Syftem. v - From the foregoing Table it Ihould 
feem , tliatail the Nlagnetical Poles had a Motion ITeft- 
ward : but if it be fo, tis evident t^iat it is not a rotation 
^bout the Axis of the jEarthj for then the Variations would 
■h'm ion- mim%U'. !'o-^-^u»im^continue 
