OBSERVATIONS AT KINGSTON OBSERVATORY. 95 
determination of the rates of the chronometer and clock every time the weather permitted, 
for upwards of two weeks before the day of the transit, and the evening of the 6th being 
very fine advantage was taken, soon after the transit was over, of observations of stars for 
ascertaining the observatory time, and the rates with all possible precision, and of com- 
pleting the examination for the azimuth. 
On the 6th, the early morning sky was overcast, as the time for the commencement of 
transit approached ; however, it became clearer, and Professor Dnpuis and I repaired to our 
posts, while Mr. James M. Dupuis was at hand to render very useful assistance in various 
ways as it might be necessary. One of the passing clouds which were beginning to disperse 
obscured the view of the first external contact, and the planet was in consequence not seen 
until it had partly entered on the sun’s disc. 
The approach to the first internal contact was noted at 9" 1™ 25°, by chronometer and 
by chronograph connected with mean time clock. 
The first internal contact, itself, that is when the limbs of the sun and planet appeared 
just to touch each other, took place as nearly as could be judged, at 9" 1" 44°, by chrono- 
meter, or 9" 18" 5°. 8L observatory mean time. For a little while after the limbs seemed 
slightly to separate, a dark shade occupied the narrow interval between them extending a 
little way on each side of the former points of apparent contact. The time when this dark 
shade began to break away and disappear occurred at 9" 2" 40° by chronometer, or 9" 19™ 
15. 81 observatory mean time: This I regard as the true time of internal contact at ingress. 
There was still some remaining haziness in the atmosphere, but as the sky was bright and 
free from clouds at the time, both of these contacts were very distinctly seen. There was 
nothing of the so-called black drop, but only the dark shade already referred to. 
The first internal contact at egress took place at 2" 25" 44. 5 by chronometer, or 2° 42" 
7. 15 observatory mean time. The dark haze seen at ingress in the morning began this 
time to be again observed at egress, but the interval during which it continued and dis- 
continuity was noted, was much shorter than inthe forenoon. The last internal contact at 
egress, that is when the outlines of the limbs appeared exactly to touch, occurred at 2" 
26™ 4.5° by chronometer or 2" 42° 27°. 15 by observatory mean time. The former of these I 
consider the true mean time of internal contact at egress. The last external contact took 
place at 2" 46™ 35°, by chronometer, or observatory mean time, 3" 2" 57°. 7. 
