on the Planet Venus. 
'57 
tions and remarks, that persons skilled in those matters may 
be better able to form a right judgment of my new computa- 
tion, which agrees excellently with the old one ; and at the 
same time may determine, whether there be inaccuracy and 
error, and on whose side it lies. 
1. The first objection is concerning the apparent diameter 
of the sun, as seen from Venus, which I have assumed at 44', 
in the computation of the penumbra, smaller, it is alleged, than 
I ought to have taken it. 
M. de la Lande puts the diameter of the sun in the apogee 
= 31' 31"= 1891". Now the apparent diameter seen from 
Venus 
1891" x dist. oils in apog. 
=Z —— —————— — — — — 9 
dist. Ven. a sole 
consequently, 
log. 1891 = 3,276692 
log. dist. o = 0,007231 
3,283923 
log. of the distance of Venus in aphel. - 9,862318 
log. of the distance of Venus in perihel. - <^856337 
log. of the diameter of the sun in aphel. 3,421605 
log. of the diameter of the sun in perihel. - 3,427586 
Diameter in aphel * = 2640", o = 44^0 
Diameter in perihel. = 2676^,6 = 44' 3 6",6 
But if the assumed diameter of the sun in the apogee 1891" be 
corrected for the irradiation, which may be put = 6" (de la 
Lande Astron. § 1388), we have 
