COKE'S OBSERVATION OF THE TRANSIT. CHRONOMETER COMPARISONS. 463 



b m s 



8. 1 1. 2 1 -5. I first perceived a break in the Sun's limb. Not trustworthy. I then changed 

 the power to 149, with the lightest red glass, and saw that the planet had 

 encroached on the limb. As I did not follow the planet until it became 

 uumistakeable, 1 have marked this observation as not trustworthy ; but I 

 believe it to bo correct. 



8. 40. 5o'2. The planet appeared to be drawing out into the shape of a pear. I was at this 

 instant obliged to remove the dark glass, and then I no longer saw the appear- 

 ance of "drawing out." It was perfectly round, with a small portion still 

 without the Sun's limb. 



8. 43. 4-5. The planet's limb appeared to be just touching the Sun's limb, a faint ligament 

 joining them (Plate XVII., Fig. 4). I believe this to be the actual time of 

 contact. The limb of the planet was very distinct and beautifully illuminated, 

 like a very young Moon. The brightness gradually disappeared towards the 

 center of the planet. I do not remember to have noticed this illumination 

 outside the Sun's limb. Whilst in contact there was a species of film, or 

 shadow, fora short distance on each side of the point of contact, which joined 

 the limbs, but did not appear to form a part of Venus, as it was much lighter 

 than the planet. This film gradually disappeared. 



8. 43. ig-5. The film or ligament getting lighter (Plate XVII., Fig. 5). 



8. 43. 46-5. It disappeared. No dark glass used. 



The "black drop " never properly formed; only a dark film. I consider 

 that contact took place at 8 h . 43'". 4 S> 5. I saw the limbs of the planet and of 

 the Sun very distinctly. 



[G. ELMSLEY COKE.] 



COMPARISONS of the SIDEREAL CHRONOMETER S. with the SIDEREAL CLOCK Baker, 

 by the Intervention of the SOLAR CHRONOMETER m, at SUPPLY BAY, 1874, 

 December 8. 



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