212 PHILOSOPHICAL TRANSACTIONS. [aNNOJ7|6. 



Some late curious Astronomical Observations communicated hy the Reverend and 

 Learned Mr, James Pound, Rector of Wdnsted, and R. Soc. Soc, N° 347 

 p. 401. 



The occultation of Jupiter by the moon observed at Wansted the l4th of 

 July in the morning, 1715. 



Having after midnight carefully corrected the clock by 10 observations of the 

 altitude of the lucida arietis, the error was found 5*" 13^ too fast, the extremes 

 not differing above 6^; and in the morning about ^^, by as many altitudes of 

 the sun, with a like agreement, the same error was found 3*" 14% to be deducted 

 from the times shown by the clock. 



July 13° P. M. N. Time by the clock. Time corrected. 



The third satellite of Jupiter was hid by the moonl3^ 27"" 33' . . . 13*" 22"" 20* 



The first satellite was hid 13 32 35. . . . 13 27 22 



The second satellite was hid 13 34 25. ... 13 29 11 



The first contact of the limbs of Ij. and ([ 13 34 54. ... 13 29 41 



Jupiter wholly hid 13 36 23 13 31 10 



The third satellite emerged 14 7 25. ... 14 2 12 



The first satellite 14 12 25 14 7 12 



The second satellite 14 14 38. ... 14 9 25 



The first limb of Jupiter came out 14 14 45. ... 14 9 32 



The following limb of Jupiter, or last contact ..14 16 15.... 14 11 2 

 The fourth satellite emerged 14 18 49 14 13 36 



Jupiter and the satellites were to the northward of the visible way of the 

 moon's centre. This occultation was observed through a telescope, in which 

 the focal length of the object-glass was 1 4-^ feet, and of the eye-glass 24- inches. 

 And the aperture of the object-glass was l-^ inch. I could perceive no colours 

 on Jupiter's limb, either at his immersion or emersion, when the axis of the 

 tube was directed to him. 



An eclipse of the moon observed at Wansted Oct. 30, 1715. 



At 15** 9™ the eclipse had been for some time begun. 



At 17*^ 39™ the eclipse was thought to be ended; and was visibly so at 17** 

 41"; but by comparing the last observations of the chords between the horns, 

 it follows that the true end of the eclipse was at 17^ 38"* 20*. At 17^ 43^" the 

 moon's diameter was 33' 40^ 



The middle cannot be supposed to be very accurately determined by these 

 observations, which were not sufficiently distant from the time of the greatest 

 obscuration. However by comparing several of them together, the middle will 

 be obtained, viz. 16** 15™ 47*. The digits eclipsed were 8|-. 



