ility for a
planet that one hesitates to accept it as proved, and almost hopes that
it may turn out to have no real existence. Venus, as the twin of the
earth in size, is a planet which the imagination, warmed by its sunny
aspect, would fain people with intelligent beings a little fairer than
ourselves; but how can such ideas be reconciled with the picture of a
world one half of which is subjected to the merciless rays of a
never-setting sun, while the other half is buried in the fearful gloom
and icy chill of unending night?

Any amateur observer who wishes to test his eyesight and his telescope
in the search of shades or markings on the disk of Venus by the aid of
which the question of its rotation may finally be settled should do his
work while the sun is still above the horizon. Schiaparelli adopted that
plan years ago, and others have followed him with advantage. The
diffused light of day serves to take off the glare which is so serious
an obstacle to the successful observation of Venus when seen against a
dark sky. Knowing the location of Venus in the sky, which can be
ascertained from the Ephemeris, the observer can find it by day. If his
telescope is not permanently mounted and provided with "circles" this
may not prove an easy thing to do, yet a little perseverance and
ingenuity will effect it. One way is to find, with a star chart, some
star whose declination is the same, or very nearly the same, as that of
Venus, and which crosses the meridian say twelve hours ahead of her.
Then set the telescope upon that star, when it is on the meridian at
night, and leave it there, and the next day, twelve hours after the star
crossed the meridian, look into your telescope and you will see Venus,
or, if not, a slight motion of the tube will bring her into view.

For many amateurs the phases of Venus will alone supply sufficient
interest for telescopic observation. The changes in her form, from that
of a round full moon when she is near superior conjunction to the
gibbous, and finally the half-moon phase as she approaches her eastern
elongation, followed by the gradually narrowing and lengthening
crescent, until she is a mere silver sickle between the sun and the
earth, form a succession of delightful pictures.

Not very much can be said for Mercury as a telescopic object. The little
planet presents phases like those of Venus, and, according to
Schiaparelli and Lowell, it resembles Venus in its rotation, keeping
always t