on the Atmosphere of Venus. 321 
■v 
1. March 23d, 5 h io', 4^ days after the conjunction, a faint 
light appeared, at times, playing along the dark limb from the 
southern cusp. The arc appeared hooked and irregular. 
2. March the 24th, f. I saw the exterior limb of the illu- 
minated part manifestly much more convex at a, fig. 4. than at 
b. I also actually saw, at present, near d , a grey, faint, 
twinkling light, proceeding from the southern cusp in an in- 
flected direction. Something of a similar appearance was like- 
wise seen at the northern cusp c ; but this was still fainter, and 
somewhat less inflected. The bright extremities of the cusps 
were very sharp, and similar in point of illumination. 
3. March 25th, f if. The bright hooked prolongations 
extending from both cusps, were not so perceptible as on the 
preceding days; but I was now the more struck on seeing, 
under the present circumstances, manifest traces of the same 
faint ash-coloured inflected streaks extending into the dark 
hemisphere, which I had beheld on the loth of March, and 
which now proceeded from the extremities of both cusps, but 
more perceptibly so from the southern. See fig. 5. 
4. March 30th, 11^ days after the conjunction. I now saw 
no more of these appearances than I had done on the 9th and 
the preceding days of this month, particularly the 2d and 5th, 
when nothing of this phenomenon could be perceived. 
As these observations, made after the conjunction, fully con- 
firm those from the 9th to the 12th of March, I shall now 
proceed to state the inferences that appear to me evidently to 
result from them. 
As there can now remain no doubt of the appearance of the 
pale ash-coloured streak of light, b, c, fig. 3. extending along 
the limb of the dark hemisphere of Venus ; and as this planet 
