, 1910-05-21

we arrive at our great sun, or his planets,
GatB Drills IKE our own dnu Ia up Dy HIN, o.
Fastly farther stIi!, until VIC reach the netrest
d those beautiful diamond Is, the stars, each
o. which Is Il mighty sua. Through this
space Il l. that tho comet has been coming
gradually nearer to US, during the past few
weeks, and this IL why it has appe ned to in
crease IN size; for everything looks larger
as It's distance from US lessons, and that is
what has happened with the comet, there
nus been no real Increase, it has only come
neurer to US, We might be ready to believe
that the increase was real from our having
no means Of Judging Of the distances Of the
heavenly bodies. That we have two eyes is
IA fine help to Us in Judging Of short distan-
cos, because each eye gives us its own PIC
ture and each picture is slightly different
from the other. When The two pictures
combine we see that the objects we are look
ing nj are solid, and we have no difficulty ia
judging the distances in tho measures we
aro familiar with. 1t is different when we
some to Judging OF the distance Of objects
miles away from US, and it is only expert
ence that will then 0nubie rs to estimate
It, the distance Of a ship on ~ island at
sea for instance OF the distance Of d bill top
or mountain peak on land. Bot ia regard to
the heavenly bodies neither our eyes MOI our
experience can give US the least help Ill
Judging of distances; these distances are too
vast and we can only look TO the astrouo-
mera to tell Us, with the help Of thor beautl-
tul instruments and elaborate calculations,
what they have learned about those wonder
full distances When we look up at the
night sky ard sec the moon sailing apparent
~ among the clouds we see that the clouds
olA1 $1,000 = E
Their ava th0n they, but there is nothing to
toll us how far back of them she really is, it
might be only u few yards the other side,
there IS nothing TO tell IT'S that She is probably
at least a hu8dTe Thousand times farther back
than those clouds that seem TO brush her face.
It's tho same III regard 10 SIZE, we see tho sun
and the moon like two discs or, perhaps bills
in the sky, occasionally wo SOC the moon like
a black ball in front Of tho SUI which ii
about covers. We kuow then that the sun
must at all events DC u little further away.
because he is back Of the moon, aud conae-
quently mast be largor, but who could guess
that the actual distance from side to side Of
the sun ls tour hunclred times rs great as tho
width Of the moon. Yet that is what the as
tronomers toll Us. They have measured the
distances Of tho sun and Of the moon, and
they know that the former Is about four huu-
dred times as far away us the latter. Thus the
sun IS four hundred times the distance, but
on the other hand no is four hundred times
"a wido,so the two things balance each other,
and the two bodies appear 10 Us TO be about
equal in size
Let ua think now Of the stars. For ausht
We onn tell by looking ut thorn they may be
as far away as the moon or as tar away as
lie sun, or much farther. Again how can
we measure the distances between them ?
Some look near together they might be a
few inches, others might be many yards
apart In fact we cannot properly speak of
theIn IN this way at alI but there is q way
to state those spaces which is reasonable, and
ut nil events enables us 10 compare them
with each other. aud that Is ulgt}ur nso0-
a're"te2tt, If We DO not understand what
thus means let US look ut the accompanying
diagram.