nverse will apply to the Southern
Hemisphere. It is something like a general rule in the case of total and
annular eclipses, though subject to many modifications, that places
within 200-250 miles of the central line will have partial eclipse of 11
digits; from thence to 500 miles of 10 digits, and so on, diminishing
something like 1 digit for every 250 miles, so that at 2000 miles, or
rather more, the Sun will be only to a very slight extent eclipsed, or
will escape eclipse altogether.

The diameter of the Sun being 866,000 miles and the Moon being only 2160
miles or 1/400th how comes it to be possible that such a tiny object
should be capable of concealing a globe 400 times bigger than itself?
The answer is--Distance. The increased distance does it. The Moon at its
normal distance from the Earth of 237,000 miles could only conceal by
eclipse a body of its own size or smaller, but the Sun being 93,000,000
miles away, or 392 times the distance of the Moon, the fraction 1/392
representing the main distance of the Moon, more than wipes out the
fraction 1/400 which represents our satellite's smaller size.

During a total eclipse of the Sun, the Moon's shadow travels across the
Earth at a prodigious pace--1830 miles an hour; 301/2 miles a minute; or
rather more than a 1/2 mile a second. This great velocity is at once a
clue to the fact that the total phase during an eclipse of the Sun
lasts for so brief a time as a few minutes; and also to the fact that
the shadow comes and goes almost without being seen unless a very sharp
watch is kept for it. Indeed, it is only observers posted on high ground
with some miles of open low ground spread out under their eyes who have
much chance of detecting the shadow come up, go over them, and pass
forwards.

Places at or near the Earth's equator enjoy the best opportunities for
seeing total eclipses of the Sun, because whilst the Moon's shadow
travels eastwards along the Earth's surface at something like 2000 miles
an hour, an observer at the equator is carried in the same direction by
virtue of the Earth's axial rotation at the rate of 1040 miles an hour.
But the speed imparted to an observer as the result of the Earth's axial
rotation diminishes from the equator towards the poles where it is
_nil_, so that the nearer he is to a pole the slower he goes, and
therefore the sooner will the Moon's shadow overtake and pass him, and
the less the time at his disposal for seeing the Sun hidden