C 4^5 ] 
be fuch a change of the Earths PoleSj it mud neceffarily 
require along time to become fenfible. 
BeGdes from thefe Obfervations it appears that tha 
obliquity of the Ecliptick has continued unaltered for 
thefe 200 Years laft paft, that is to fay that the Angle 
wlEch the Earths Axis makes with the plain of the Eclip- 
tick or Orb wherein fhe moves annually round the Sun^has 
been without fenfible Change in all that time ; which will 
be very hard to conceive, if we allow a tranflation of the 
Earths Poles ; for the direftion of the Axis being perfefl- 
ly at Liberty, it muft be purely cafual, if it fo hit, that af- 
ter fuch change, it make the fame Angle with the Eclip- 
tick as before. 
A farther argument of this flownefs of the change of » 
the Poles is the Latitude of Alexandria^ the habitation of 
thofe Famous Afironomers of antiquity Eratojlhenes^ Timo- 
charisy Hifparchus and Ptolomy^ and for that realbn it may 
be concluded that this of all the Latitudes the ancients has 
left us, ought to be one of the moft correft. This by P^^?- 
lomy is {kid to he pgr. ^%?n. North, (which he ufes in 
all his computations in his Jfe^^//?, and feems derived 
from the proportion of the Gnomon to its Equinoftiai 
fhadow, as 5 to 3 ) but in his Geography^ 5 fgr. juft. In the 
Year 1638 the curious^and Ingenious Mr. Gr^/^w/, when 
he went to vifit the ALgyftian Pyr amides^ of which he has 
given fo good an account, did with a fufficient Inftru- 
ment obferve the Latitude of Alexandria, and found it 
3 igr. 4m,0Y 6 minutes more than it is reputed by Ptolomy, . 
and before him by Eratofihenes fo that in about 2000 
Years the Latitude of Alexandria has altered only a few 
minutes, and fo few that the accuracy of the obfervations 
of the ancients may well be queftioned: But both being 
granted,this motion will amount to no more than a degree 
in 20000 Years. 
This is faid not with intent to invalidate what Mr. 
Hook hath from fo good grounds advanced, viz. that the 
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