136 Mr. Schroeter's new Observations 
same as those of the 26th and 27th of February: yet the 
appearance is very little different from that of the abovemen- 
tioned days, when the shadow, fig. 4. at length penetrated 
quite through, and the separated part was perceived as an in- 
sulated bright point. Now if it be considered, that on the 28th 
of February, only 24 hours later, this appearance recurred, but 
was not exactly the same ; and that when a very extensive 
mountainous southern region forms the edge of the planet in 
various degrees of obliquity, according to the respective situa- 
tions of Venus and the earth, the phenomena must naturally 
be so diversified ; there cannot be the least doubt, but that the 
same southern range of mountains, which occasioned the simi - 
lar appearances of the 26th, 27th, and 28th of February in the 
evening, also produced this of the forenoon about 11 o'clock, 
according to the rotation ; especially as no intervening obser- 
vation contradicts this conclusion. The effect of small dif- 
ferences in the position of planets, may be exemplified from 
the late eclipse of the sun on the 5th Sept. 1793, when the 
projections of the mountains Leibnitz and Doerfel, bounding 
the southern edge, were so different from those of the older 
observations, under a similar variety of circumstances. The 
abovementioned conclusion with respect to Venus becomes still 
more evident and remarkable, from its agreeing more exactly 
than could be expected, according to the circumstances, with the 
period of 23 hours 21 minutes, which, in my memoir on the rota- 
tion of Venus, I had determined as near the truth: for on the 27th 
of February that appearance took place about 40 minutes earlier 
than the evening before ; and the middle of the time when the 
southernmost part of the southern horn appeared as a sepa- 
rated point of light (a phenomenon similar to the present), 
