158 - . THE I'OUNG SCIENTIST. 
the coast of Peru, Ecuador and Colombia, and 
throughout Panama and Central America. 
The most thickly populated portion of Aus- 
tralia will be favored with a very small eclipse 
just after sunrise, the limiting line (where the 
eclipse ends at sunrise) passing about midway 
between Adelaide and Melbourne. As the path 
of total eclipse passes over no favorable point, 
but little effort will be made to secure observa- 
tions ; still, one or two small expeditions have 
set out for some of the " South Sea Islands." 
Inasmuch as the Moon moves from west to 
east in its orbit, its shadow must pass from 
west to east over the earth. 
Sun's limb. And the further from the node, 
inside of the solar ecliptic limit, 17°, on each 
side of the node, or 'S4P, the Moon is, the 
smaller will the eclipse be. The period occupied 
by the Moon in passing over this portion of her 
orbit may be called, for convenience sake, the 
eclipse season, which is of about twenty days 
duration. Fig. 5 represents the equator of the 
heavens, c d ; the earth's path, F G, and the path 
described by the Moon's nodes, e h. It is evi- 
dent that eclipses can only occur at a limited 
distance each side of a and B, the two nodes, or 
from ct to 6 on each side of a. 
It must be remembered, in this connecUon, 
Fig. 2. 
Fig. 3. 
Fig. 4. 
The Moon produces a total, partial or annular 
eclipse of the Sun wlienever she passes within 
17° of one of her nodes at the time of New 
Moon, and if this event occurs at the time of 
perigee, a total eclipse occurs, for then the 
Moon's umbra, which is only about 234,000 
miles long, touches the earth. The nearer the 
Moon is to the earth the wider will be the belt 
that the Swa's apparent path tlirough the 
heavens is the earth's true patli. 
THE PLANETS.— MAY, 1883. 
(All Computcitious are for the Latitude and 
Meridian of New York City.) 
MEECUKY AND JUPITER. 
These planets are evening stars. Mercury 
Fig. 5 
of totality and the greater its duration, because 
the diameter of the umbra will be greater. If 
the Moon reaches her node exactly at the time 
of conjunction, i.e., directly in a line between 
the earth and Sun, at the time of Apogee, then 
an annular eclipse occurs, because the apparent 
diameter of the Moon is less than that of tho 
Sun (see Fig. 4), and when at perigee, or 
nearest the earth, then the eclipse must b'> 
total, for then the apparent diameter of the 
Moon is equal to or exceeds that of the 
Sun. But when the conjunction occurs near 
the node, a partial eclipse must occur, cut- 
ting off (Figs. 2 and 5) only a portion of the 
being the most western, Jupiter being about one 
hour or 15° east of Mercury. They set as fol- 
lows : 
MERCURY. 
May 10- 8h. 55m., 33° 16' N. of west point, and 
9° 49' N. of sunset point. 
May 15 -9h. 2m., 33° 55' N. of west point, and 
7° 59' N. of sunset point. 
May 20— 8h. 58m., 33° 29' N. of west point, and 
6° 38' N. of sunset point. 
JUPITER. 
May 10 -lOii. 21m. eve. 
" 20— 9b. 51m. 
« 30— 9h. 20m. " 
