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[ 340 Obfervers therefore ()mold be Rationed farther to the

wa about Cape Corientm; at which place and at Mexico, though in about ao째 of N. latitude, the effed of parallax will Rill be con6derable, particularly at the egret's, as appears from the follow ng Table.

Places.

re:al f31.11",L. FrIrf.

taa. costal. EM:1;:e.

exico Cape Cotientes I

07

o 26

o

s 03 I 0 to 5 oo 5 26

I7

o

t7 o6

By computing the obf rvations to be tn de at either of the above places, or 'n any of the neighbouring parts, with thofe of To nes% difference of more

than ferenteen minute. in the total duration may commodioufly be obtained ; by which the quantity of the fun s parallax may he determined agreeably to

the method propoled by Dr. Halley in the cafe of the laft tranfir, and in which no error but that of the obfervation can take place, fuppoling the &nation of the two places to be nearly known. When Dr: Halley's computation was examined, 2nd it was found that fo great a difference in the total duration of the tranOt at any two places as had been expelled could not conveniently be obtained ; another Method was propofed, and was accordingly carried into execution, viz. to Ration two obkrvers in fueh a manner that' One of the internal Minuets might be obleded with the greatell difference yollible anfing from a contrary effed of parallax at the two places. This method, though neceatily inadequate, becaule

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