The Portland daily press., 1900-05-18

IN. Y. Post
On May Is We shall have an opportun
ity 10 sse an uncommon astrcnom ioal &C
oufrenes. The sun Will b totally eolipset
and the svent will be visible In parts o
the United states.
Occasionally. a. We know, the moon
passss between US ava the sun, cutting
OF the latter's light o,nipietsiy. This We
call solar .eclipss. Lunar soiipsss, on
tvs other hand, are caused BY the moons
reaching suoh aposition that the earth
10 directly bat wesn 10 and the sun. The
moon has no inherent hrilliapcy like the
sun; 1t shinss only BY rsfisctins soias
light; aud whom the light is ont on, the
moon simply "goss out." But the sun
IL s.if-lumisous, and 10 In reality shin
ing lust the same whom under eclipse 81
~ any other time. Thus We arrive at
this Fundamental dif ,rsnos between
lunar and solar eolipses. In the former,
the moon having suddenly ceased to re-
oeive or retieot light. the eclipse 10 obssrv-
able wherever the moon. II uneolipsed
would be visible. But Mt any given
moment we oan usually see the moon
from one-half the earth's surface. Oonyt.
qusntly, II q lunar eclipse takes place, q
majority OF the sarth's Inhabitants have
On opportunity to observe IL, and thus q
lunar eclipse is something that almost
any person can remsm Der TO have seen.
But 10 10 very different with the sun. Al
We have said, he continues TO give light
when collapsed: 30 that 1t II only In plaoe
where tbs sun 10 actually covered up by
the moon that he will ssem to be-
collapsed. The moon under eclipse 10 II Ike
candle that has been sxtinsuished; IL
10 dark whatever side we look at It, But
which will be invisible to him only whose
view 10 obstruotsd by the interpoiision Of
soma opaque otjsct.
That opaqus obect IL the moon. But
shs II comparatively small, and eannos
render the sun totally invisible from
more than tiny circular or oval spot on
the earth's surface. liz the eclipse Of
May 30 thst little spot will be only about
seventy five miles wids; and II the moon
were not in motion. the total phase Of
the eclipse could be sfen uowhere else.
But the moon 10 travelling all the time
through space In Its orbit around the
earth. 80 tbs little spot II moving. tao.
and changing Its position gradually upon
the earth's sol faos. Thus, instead OF a
spot, we shall have long strip or band
about seventy live miles wide; and BY
weiiiug for the right moment, 1t Will be
possible g see sotAIity from any point
much a. though there were huge
pseeil, with Its point touching the earth.
and having Its other end Iivoted TO tbs
sun. II the moving moon were than also
attached to shis pencil somewhere near
the point, she would draw the pencil
eclipse path on our earth. ALy ops
standing In that path could then look
along the pencil, and at the proper
moment see the moon covering the sun,
and obsouring his Hight. In places aitu-
ated near this path OF totality, a. Il 10
o. He'd, we shall be able TO see the eclipse,
but not as total one. Fer such places
the moon will oovsr the sun only In part.
so that some Of bis brilliant surface will
remain In sight. The amount Of obscurs-
ton always depends upon the observer 9
nearnsss TO the totality line. The nearer
he Is, che more nearly total the sclipss
will be.
On May Is the path OF totAiity begins
In the Pacific Ocean just west Of Mexico.
There the point OF the huge pencil We
have imagined first touches our earth.
IL then passes eastward across Mexico.
ana entering the United States near New
OrlesnA proessds In . northsastsriy
close to Norfolk, Va. Than 10 crosses the
Atlantic, touches Portugal, ana aftsr-
wards passes across north ,rn Africa lsAs-
ing the earth finally near she northern
.nd nf the rcd Sea. In this country the
cities Of New Orleans. La; Mobile. Ala.
Rafa twh AnrHoIk Va al
on the totality patti. Al New OrlsxnA
the sun will be completely covered ct 7.s0
a. M, while AZ Norfolk this will not
happen unttl sos q. N. In the former
city totality will last 10 seconds, and In
the latter 102 seoonds. AZ intsrmsdiats
totality will fall between these extreme
values For places nearer % New Or
leans than to Norfolk the members will
b. nearer those given for New Orleans,
and vios vsrea.
Having thus explained the circum-
stances Of this eclipse. We sball now
touch upon some OF the interesting thinss
that will be seen II the sky b clear.
Total solar eolipses appeal equally 10 the
general public and 10 the professional
astronomer. On the one hand they
present ths most superb spscta,is uithin
she whole range OF astronomy; and On
the other. they offsr tne hest opportunity
competition OF our sun. One Of the
thinRs 90 which astronomers attach Inn
portancs 10 tho accurate observation Of
che times Of beginning and sndlng or the
eclipse. 1t 10 easy to see that the mashe-
matioAl considerations upon which are
bassd our tbsoriss OF lunar molten will
be put to a very severe tsst 10 predisting
the exact instant when the sun will be
covered up By the moon. II observation
agrees with nrsdistion We have the
strongest eorroborative evidence OF the
correctness Of our theory and OF eur
numerical calculations. On the otheF
hand. II &c be round that the predictions
are slightly In error, the amount Of that
error can be determined By observation,
and mathematical theory thus corrected
for the benefit Of future predictions.
Although cur knowledge In THE depart
went OF ait -onomy has reached Q very
high state Of rerfsetion, 10 IL fast that