[ ] 
Venqs patted the meridian in the tranfitory at 
i k 37' 55" afternoon by the clock: the fun pafs’d 
this day at n k 57' 27"; and yeflerday, the iy, at 
1 i k 57' 5 whence it is eafy to reduce all to ap- 
parent time, as follows : 
4 »/// 
Total ingrefs of Venus i75i,Apr. iy 22 
Her total emerfion 23 
Her meridian tranfit * — 16 01 
Now, fuppottng the whole dilk to 
have taken up one minute, as it 
feem’d thereabout, both in the ingrefs 
and egrefs, the middle of the occul- 
tation muff have been — 15 22 
And the duration, with refpedt to 
the centre of Venus . 
42 02 
15 47 
40 29 
S8 2+V 
33 45 
In this account I have been the more particular 
as to circumftances, in hopes to point out, in fome 
meafure, to fuch, as may not be much converfant 
in obfervation, how to provide, and what to do, 
on a like occafion ; but more efpecially to recom- 
mend the more frequent ufe of the polar axis ; the 
great conveniency whereof I have frequently expe- 
rienced, not only in readily finding and eafily pur- 
fuing a celeftial objedt, by day as well as by night, 
but in many other regards , as in comparing un- 
known phenomena, as comets, with known 
ones, in any fituation, only by the addition of a 
graduated fedtor j according to Mr. Graham's excel- 
lent contrivance ; in meafuring diameters, and repeat- 
ing the menfuration, as faft as you pleafe, with the 
micrometer i which, in this way of application, 
admits 
