368 



TRANSIT OF VENUS, 1874. RODRIGUEZ. POINT VENUS. 



not so well as the first Internal Contact had been. I was, however, enabled 

 to note it to the fraction of a second. 



I now put in the double-image micrometer, intending to make measure- 

 ments of cusps ; but clouds prevented my making more than two measure- 

 ments. I, therefore, replaced the Airy eye-piece, and I was fortunate enough 

 to catch sight of the planet about three minutes before it disappeared ; and 

 the last phenomenon I noted was the disappearance of the little black notch 

 in the straightening of the Sun's limb at 15 h . 50 m . 28 s '0, and immediately 

 afterwards I compared the three clocks as before. On the planet leaving the 

 Sun I failed entirely to see what I had seen at Ingress, namely, the preceding 

 limb on the external segment of the planet projected against the dark space 

 beyond. With reference to the dark ligament, to which I have alluded, 

 I may mention that at no time did it appear perfectly black ; even immediately 

 succeeding and immediately preceding the first and second Internal Contacts 

 respectively it was a degree less dark than the planet. In this particular 

 it differed from that which, according to my impression, the " Model " pheno- 

 mena showed. During " Mid-transit " I examined the planet with various 

 eye-piece powers, and it appeared to me to have a very slight ellipticity, the 

 greatest diameter being inclined about 30 to the path of the planet. 



COMPARISONS of the EQUATORIAL CLOCK MOLYNEUX with the TRANSIT CLOCK 

 GRAHAM 2, by the intervention of the SOLAR CHRONOMETER CARTER 410. 



* An error of 10". in one of the readings. 

 The chronometer Carter was losing 7 s -5 daily on mean solar time. 



