e the Moon is to a certain degree
in the way. From C no eclipse is seen, because the Moon does not come in
the way.

It is to be noted that in a Partial Eclipse of the Sun, the position A
lies _outside_ the surface of the Earth.]

An _Annular eclipse_ is an eclipse which just fails to become total for
yet another reason. We have pointed out that the orbits of the various
members of the solar system are not circular, but oval. Such oval
figures, it will be remembered, are technically known as ellipses. In an
elliptic orbit the controlling body is situated not in the middle of the
figure, but rather towards one of the ends; the actual point which it
occupies being known as the _focus_. The sun being at the focus of the
earth's orbit, it follows that the earth is, at times, a little nearer
to him than at others. The sun will therefore appear to us to vary a
little in size, looking sometimes slightly larger than at other times.
It is so, too, with the moon, at the focus of whose orbit the earth is
situated. She therefore also appears to us at times to vary slightly in
size. The result is that when the sun is eclipsed by the moon, and the
moon at the time appears the larger of the two, she is able to blot out
the sun completely, and so we can get a total eclipse. But when, on the
other hand, the sun appears the larger, the eclipse will not be quite
total, for a portion of the sun's disc will be seen protruding all
around the moon like a ring of light. This is what is known as an
annular eclipse, from the Latin word _annulus_, which means a ring. The
term is consecrated by long usage, but it seems an unfortunate one on
account of its similarity to the word "annual." The Germans speak of
this kind of eclipse as "ring-formed," which is certainly much more to
the point.

There can never be a year without an eclipse of the sun. Indeed there
must be always two such eclipses _at least_ during that period, though
there need be no eclipse of the moon at all. On the other hand, the
greatest number of eclipses which can ever take place during a year are
seven; that is to say, either five solar eclipses and two lunar, or four
solar and three lunar. This general statement refers merely to eclipses
in their broadest significance, and informs us in no way whether they
will be total or partial.

Of all the phenomena which arise from the hiding of any celestial body
by one nearer coming in the way, a total eclipse of the sun is far the