THE GUIDE TO NATURE 
172 
have seen it at other times. There is a 
brighter belt at the equator and certain 
poorly defined spots, but no conspicu- 
ous details. Not only has the ring van- 
ished but its light is lost and the planet 
is only about half as bright as when the 
ring is in good view. The magnitude 
Figure 3. The rings of Saturn as seen 
now and as seen when widely opened. 
at this time is 0.7 at its opposition. In 
1915 its magnitude was 0.2, the differ- 
ence being due to the position of the 
ring. At present Venus, with its nar- 
row crescent, is much more interesting 
to the ordinary person than is Saturn. 
Although Venus comes closer to the 
earth than any of the other principal 
planets, and to us is the brightest of 
all, our knowledge of the conditions of 
the planet are not as complete as in the 
case of most of the other planets. When 
Venus is close to us, as now, it is in 
almost the same direction as the sun, 
and is thus nearly invisible in the sun’s 
rays. At this time, also, it exhibits 
merely a narrow crescent, so that but 
little of the surface of Venus is seen 
even under these poor conditions. Cer- 
tain markings or shadings have been 
asserted to exist, but their existence 
has not been proved. When the planet 
passed between us and the sun, as it did 
in 1874 and 1882, there was definite evi- 
dence that it was surrounded by a dense 
atmosphere. Hence we probably can- 
not see the surface itself. Since we 
cannot see any definite markings on the 
surface we cannot determine the period 
of rotation of the planet. Some have 
claimed that the vague markings which 
they saw indicated rotation in a little 
less than a day. Others claim the pe- 
riod is the same as that of its revolu- 
tion about the sun, or 225 days, so that 
it keeps the same face toward the sun 
at all times, just as the moon keeps the 
same face toward the earth. We can 
only say at present that we know noth- 
ing positively either about the surface 
details or the period of rotation of the 
planet. 
Again, as Venus has no satellites, its 
mass cannot be determined with the 
same accuracy as is possible in the case 
of planets which have satellites. As 
seen in a telescope, the planet appears 
simply as a brilliant object, showing 
phases but lacking the interesting de- 
tails which some planets show. The 
more remote and less brilliant planets 
yield us more information than Venus. 
The atmosphere of Venus and its size 
make it more like the earth than any 
other planet, and conditions on the 
planet are probably nearer like those 
on the earth than those of any other 
planet. 
April. 
BY FREEMAN FOSTER BURR, WHITE PLAINS, NEW YORK. 
Red are the maple buds, 
Green are the fields; 
To the warm April rain 
All the world yields. 
Blackbird from meadow tree, 
Bluebird from sky, 
Call to the soft’ning mold 
Where the flow’rs lie: — 
Bloodroot and adder’s tongue, 
Columbine red, 
Nodding anemone, 
Winter is fled; 
Spread to the sun your leaves, 
Wake to our call; 
Catch in your petal-cups 
Raindrops that fall. 
Robin and meadow lark 
Whistle and sing. 
Welcoming back again 
April and spring. 
Plant a Tree. 
BY DAVID H. WRIGHT IN “THE CONSERVATIONIST." 
If when I am gone 
Thou would’st honor me. 
Then plant a tree. 
Some highway, bleak and bare, 
Make green with leaves. 
So radiant and fair 
And full of leaves, my monument will be 
So ever full of tuneful melody. 
My monument will be 
A sight most rare — 
Trees planted everywhere. 
A highway broad from city to the sea. 
Plant this in memory of me. 
