CELESTIAL DAY OBSERVATIONS. 
Ill 
the aperture in both cases undiirinished. It appeared brighter 
than Aldebaran. August 23d. Oh. 12' P. M. saw the star Ca- 
pella or a /iuriga:, with a power of 6o, and immediately after- 
wards with a power of 30 ; the aperture undiminished. With 
this last power it appeared extremely distinct, but not so bril- 
liant and splendid as with the former power. Having dimi- 
nished the aperture to nine-tenths of an inch, it appeared on 
a darker ground, though, in the former case, it was equally 
perceptible. A few minutes afterwards, could distinguish it 
with a power of 15 ; tho aperture being contracted to half an 
inch. It appeared very small j it was with difficulty the 
eye could fix upon it in the field of the telescope ; but 
when it was once perceived, its motion across the field of 
view could be easily followed. Could not perceive it when the 
diminished aperture was taken away. 
, August 10. 9I1. 30' A. M. Saw the star Sirius, with a power 
of 60, the aperture contracted to nine-tenths of an inch. Saw 
it likewise when the aperture was diminished to half an inch, 
but not nearly so distinct. Saw it also when the aperture re- 
mained undiminished, but not so distinctly as through the aper- 
ture cf nine-tenths of an inch. Having put on a power of 
30, could distinguish it distinctly enough through each of the 
former apertures, and also when they were removed, but some- 
what more distinctly with the apertures of nine-tenths and half 
an inch, than without them. At this time the star was2h. 42' 
in time of right ascension west of the sun, having an elevation 
above the horizon of about 17° 10' j the sun shining bright, 
and the sky very much enlightened in that quarter of the hea- 
vens where the star appeared. There was also a considerable 
undulation in the air, which is generally the case in the hot 
mornings of summer, which renders a star more difficult to be 
perceived than in the afternoon, especially when it is viewed at 
a low altitude. June 4th. ih. 30’. Saw Sirius, uith a power 
of 30 with great distinctness ; the aperture not contracted. 
The star was then Ih. 50 in time of right ascension east of 
the sun. August 24th. ph. 5' A. M Saw the star Procyon, or 
« Cants Minoris, distinctly with a power of GO, the aperture 
Obstrvations 
upon tixpil 
siars iu tlic 
day-tiiue. 
