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contact happened at io b .i2'. 17", 5. and at the Royal 
Obfervatory, by a mean of all the obfervations at Paris, 
at io h .2i'.33' / . The difference of longitude therefore 
is 9k 15", 5. And if we take a mean of thefe 7 re- 
fults, the Royal Obfervatory at Paris will be found to 
be 9'. 1 7" 4. to the Eaft of the Royal Obfervatory at 
Greenwich, a determination very nearly agreeing with 
that mentioned by Sir Ifaac Newton, and which, I 
believe, was deduced from a companion of Dr. Hal- 
ley’s and Mr. Caffini’s obfervations. 
The Abbe de la Caille, in his memoire on the par- 
allax of the Moon, fuppofes the difference of meri- 
dians to be g'.iy" tho’ he has not mentioned from 
what authority he drew that conclufion. I fhalL 
therefore fuppofe the difference of meridians to be 
9 / - 1 7 / - — The laft internal contadt was oblerved at 
Paris by Mr. de la Lande at 20 h .28 / 25" or 26" ; at 
2o h .28 / .26 // by Father Clouet, and by Mr. Maraldi 
and Mr. Barros feparatelyat 2o h .28 / .42 Mr. Pin- 
gre, in a very curious memoire on the Sun’s parallax 
already referred to, fuppofes the internal contacft to 
have happened at Paris at 2o h .28'.38 // . 1 fhall 
therefore make ufe of the Abbe de la Caille’s obferva- 
tion at 2o h . 28k 37" 4. 
The difference of meridians between Paris and 
Stockholm, fays Mr. Wargentin, is i*».2'.5i"or 52" at 
moff. Mr. de la Lande from a comparifon of 17 
obfervations of the firft fatellite of Jupiter made from 
1750 to 1759 and communicated to him by Mr. 
Wargentin, determines the difference of longitude 
to be i h .3'.ro". And the Abbe de la Caille, in his 
memoire on the Moon’s parallax, fuppofes it to be 
i h .3'.i3". As thefe two laft determinations agree fo 
pearly together, I fhall fuppofe Stockholm to be 
R r r 
