652 I'HILOSOPHICAL TRANSACTIONS, i , [aNNO J 762. 



r Interna] contact at h. m. s. From Longitude h. ra. s. From. 



, Abo at 9 45 59. . Phil. Trans from Paris = 1 19 17 e. Phil. Trans. 



Tornea at. . 9 54 8. . ditto from Paris = I 27 28 e. ditto 



Cajaneburg at. . 10 S 59. . Swedish acts . , from Stockholm = 39 20 e. Swedish acts 



Cape of Good Hope at. . 9 39 48. . Phil. Trans from Greenwich = 1 13 35 e. Phil Trans. 



9 39 52. 



As there were several observers at some places, I have therefore set down the 

 two extreme observations, that I may afterwards take the mean of them. One 

 reason I apprehend why the observers, even Observers. DifF. in obs. 

 at the same place, differ some seconds in the ^' BoTognt!'^' .' '. : ! '. 4. ! \ ] V.Z 6 '^''' 

 time of the contact, may arise from this, that Parist 6 = 16 



some of them judged of the contact when ctmbridgr!''. ! .' 2. '. '. '. \\Z 7 



there was no light between the limb of Venus Stockholm 2 = 3 



and that of the sun, others did not imagine Tornea 2 — 14 



the contact to happen till they lost a part of Cape of G. Hope 2 . . = 4 



the circumference of Venus; I shall there- Carlscrona 2 = 6 



fore set down the difference between the observers at the same place, that an esti- 

 mate may be formed of the limit of this error. 



"*' The mean therefore of all these comes out to be = 6^6, an error that may 

 be committed in judging of the contact, even at the same place. 



After having computed the parallaxes of longitude and latitude, on the suppo- 

 sition that the sun's parallax was = 8-i-^', for each of the above places, I com- 

 pared the observation at each place with the observation at the Cape of Good 

 Hope, and deduced the sun's parallax from each, as may be seen more fully in 

 the following table. 



1 



h. m. s: m. s. 



9 39 50 Cape 6 8 Cape 



1 13 35=D. M.I llGreenw. 



8 26 15 7 19 



8 19 Greenwich 



— 4 



7 15 sun's parallax = 8".42 



h. m. 8. m. s. 



9 39 50 Cape 6 8 Cape 



I 32 7=D.M: 1 4Le8keard 



8 7 43 7 12 



8 21 Leskeard + 10' 



7 22 sun's parallax := 8".69 



h. m. s. m. s. 



9 39 50 Cape 6 8 Cape 



1 17 36=D.M. 1 12Shirburn 



8 22 14 7 20 



8 15 12 Shirburn — 18' 



7 2 sun's parallax 8'. 15 



h. m. s. m. s. 



9 39 50 Cape 6 8 Cape 



1 4 25=D.M. 54 Paris 



8 35 25 7 2 



8 28 27 Paris 



6 58 sun's parallax .= 8".42 



3 

 h. m. 8. m. s. 



9 39 50 Cape 6 8 Cape 

 1 14 5=D.M 1 11 Saville house 



8 25 45 7 19 



8 IS 22 Saville house + 4" 



7 23 sun's parallax = 8".57 



6 



h. m. s. m. s. 



9 39 50 Cape 6 8 Cape 

 28 20=D.M. 29 Bologna 



9 11 30 6 37 



— 4"6 4 57 Bologna 



— 4" 



6 33 sun's parallax = 8".4I 



* In the Phil. Trans, it is at 9h 46' 59I", but that this is a mistake, in writing down the minutea^ 

 may be easily proved. —Orig. 



■f M. de la Lande, in a letter to Mr. Maskelyne, says that M. de la Caille observed with a tele- 



