58 



PHILOSOPHICAL TRANSACTIONS. 



[anno 1763. 



Diff. ofcalcu- Diff. ofobser- Son's Par- 



* ■ allax. 



Placet, laled times, veil times. 



Greenwich 7"" 47'.72. . 7" 



Paris 7 i'8.40 . . 7 



Stockholm 8 53.72 .. 8 



Upsal 9 1-83 ..8 



Cajaneburg i) 4'2-30 . . 9 



Tobolski 10 29- 6.. 10 



Tornea" 9 48-95 . . 9 



Places. 



Abo 



Hernosand .... 9 

 Rodrigues. ...... 3 



Gottingen 7 



Bologna 7 



Florence 6 



Rome 6 



Diff. of calcH- Diff. ofobser- Sun's Par* 



lated times. ved times. allax. 



. 9"° ir.l6. .8-" 59' ..8".301 



21. 17. .9 1 ..8.676 



19.72.. 2 13 ..5.993 



54.36.. 7 31 ..8.558 



3.31.. 6 41 ..8.525 



57.79 .6 36 . . 8.536 



45. 16.. 6 41 ..8.907 



Such is the result of a comparison of the best observations, made in places 

 whose longitudes are as accurately ascertained as the present state of astronomy 

 will permit ; by a mean of the whole, rejecting only the observation at Rodrigues, 

 the sun's parallax on the day of the transit is 6".6q2. — Mr. H. has excluded the 

 comparison of the observation at Rodrigues, because the parallax resulting from it 

 differs so considerably from the rest. If we suppose the internal contact to have 

 really happened one minute sooner, through a mistake in writing down the obser- 

 vation, the parallax will then be 6".6g7. 



This observation made at Rodrigues, supposing it exact, will furnish another 

 term with which to compare the several observations made in Europe. The sun's 

 parallax resulting from each observation may be seen in the following table. 



Greenwich 



Pans 



Stockholm 



Upsal 



Cajaneburg 



Tobolski 



Tornea" 



Abo 



Hernosand 



Gottingen 



Bologna 



Florence 



Cape of Good Hope 



Diff. o I 



cakulaled 



times. 



4">2'''. 00 



4 8.98 

 39.00 

 42.11 

 22.58 



9-34 

 6 29.23 



5 51.46' 



6 1.45 

 4 34.6+ 

 3 43.59 

 3 38. 7 

 3 10.72 



DilF. of 



observed 



times. 



5"" 11". 

 4 50.5 



28.5 



32 



"9 

 5.5 

 25 

 47 

 49 

 18 

 33 

 23 

 13 



Sun's 

 parallax 



10".444 

 10.500 

 10.314 

 10.312 

 10.327 

 10.177 

 10.289 

 10.422 

 10.183 

 10.421 

 10.787 

 10.854 

 5.993 



Diff. of 



observed 



times. 



4"'ll'. 

 3 50.5 



28.5 



32 



19 

 5.5 



25 



47 



49 



18 



33 



3 23 

 3 13 



Sun's 

 parallax. 



8".429 



8.332 



8.721 



8.734 



8.915 



8.919 

 8.902 

 8.886 

 8.690 

 8.45+ 

 8.372 

 8.449 

 8.697 



The mean of the whole, rejecting the comparison of the Cape, is Waiq; 

 supposing the internal contact to have happened at o" 36"" 49'. But if a mistake 

 of one minute was really committed, the 3d column will receive a considerable 

 alteration, and the parallax resulting from each observation will be represented in 

 the last column, the mean of which is 8".654, agreeing as nearly as possible 

 with the parallax resulting from all the best observations compared with the 

 Cape. 



Mr. Pingre finding the parallax resulting from his own observation, to differ 

 so widely from that deduced from the Cape, and that both observations might be 



