[ 231 } 
dien would the edge of the Sun be unlverfally 
fluctuating or trembling; but as this was not the cafe, 
the undulation mufl; be Imputed to fome other caufe, 
not improbably to an atmofphere about Venus. I 
am the more minute on this circumflance, becaufe 
you yourfelf. Sir, in a late * publication, have taken 
notice, that when I took the obfervation of the tran— 
fit of Venus at Madras, in the year 1761, I faw 
a kind cf penumbra or dujky JJjade, which preceded the 
jirji external contadl two or three feconds of time, and 
was Jo re^narkable, that I was thereby ajfured the contadl 
was approaching, which happened accordingly. 
Upon your foregoing paragraph I mufl; beg leave- 
to make the following remark,, that in the tranfit of 
this prefent year I did not take notice of the fame 
phaenomenon as I did of the tranlit of Venus in In- 
dia, in the year 1761 ; but I mufl: here again infifl: 
upon it, that fuch penumbra or dulky fhade I then 
adually faw, but I do not recolleCt I then faw the 
leafl: undulation, ebullition, or corrufcation, as hap- 
pened in the tranfit of this prefent year. Yet both 
phasnomena were conducive to the fame purpofe, and 
ferved to give me notice of the near approach of the 
planet Venus to the folar difc, the event, in both in- 
flances, juflifying the prefage. ; and both appearances 
might be the confequences of the fame caufe; which 
caule, as I have before obferved, might be nothing 
lefs than the atmofphere of Venus. I fay might be, 
for I would not be underflood to aflert here any 
Inftruftions relative to the obfervation of the enfuing tranfit 
of the planet Venus over the Sun’s difc, on the 3d of June 1769. 
By the Rev. Nevil Mafkelyne, Aftronomer Royal, p. 321. 
thing. 
