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it will end in the North Sea with the fetting Sun, in 
105 degrees eaft longitude, and 72 degrees north lati- 
tude. 
If the motions of the Sun and Moon were equa- 
ble, any given eclipfe would always return in a courfe 
of 223 lunations, which would conlift of 18 years 
1 1 days 7 hours 43 minutes 20 feconds (as wasobferv- 
ed by the antients) for 1388 years; and would for 
ever do fo, if, at the end of each period, the Sun and 
Moon fhould be in conjunction either in the fame 
node, or at the fame diftance from it as before. But 
that is not the cafe : for, if the Sun and Moon are 
once in conjunction at 18 degrees diftance from the 
node, which is the greateft diftance at which the 
Moon’s fhadow can touch the earth, at the next pe- 
riod of 1 8 years 1 1 days, &c. the Sun and Moon 
will be 28 minutes 12 feconds of a degree nearer the 
fame node than they were at the period laft before. 
And fo by falling gradually nearer and nearer the 
fame node every time, the Moon’s fhadow will pafs 
over the center of the earth’s enlightened difc, at the 
end of the 38th periodical return of the eclipfe from 
the time of its firft coming in at either of the earth’s 
poles ; becaufe the conjunction falls in the node at the 
end of the 38th period. 
In each fucceeding period, the conjunctions of the 
Sun and Moon will be gradually farther and farther 
from the node, by the quantity of 28 minutes 12 fe- 
conds of a degree; which will caufe the Moon’s fha- 
dow to pafs over the difc of the earth, farther and 
farther on the oppofite fide from its centre, till it 
quite leaves the earth, and travels in expanfion for 
about 12,492 years, before it can come upon the 
earth again at the fame pole as before. 
The 
