New-York tribune., 1873-01-15
THE GREAT BEAR.
LECTURE BY MISS MARIA MITCHELL

House in Grammercy Park last evening listen to q
lecture by Mss Maria Mitchell, Professor OF Astronomy
vassar College Although her subject was the Con
steaton OF the Great Bear" she rceounted the results
OF researches in the armament sketching the progress
OF Astronomy from the earliest knowledge 10 the latest
discoveries giving the story in pleasant coIoquiai
way which attracted and retained the attention of her
hearers The first few sentences lost In the buste
and stir caused by the entrance OF daory hearers but
the following is careful abstract of the lecture:
THE LECTURE.
After pcturing the general view OF the heavens she
said that the Arabians the first to study the sci
ence They we're fond OF visible Objects and used tho
parts Of the human figure symbols and attached them
10 the different consultations. SO that know star
when we sec IT, IL makes very little difference what We
call it. The seven OF the Great Bear have been
spoken OF from very ancient times They are the seven
sages OF the Hindus, also called Chariess Wsin ana
commonly the Dpper They are mentioned in tho
Princess" and in almost every poem you Will IND some
allusion TO these stars They were named about 1900
years ago. after certain letters Of the Greek alphabet
The two stars which point to the polar star may be taken
as a reference line. great many Intelligent people
will use very uncertain means OF Judging. You very
often people speak of seeing meteor as large as
plate Such expressions absurd. These two stars
will answer very well for measure. being about Two
degrees apart.
There is another thing about these stars In color no
two alike. The human better than any tele-
in color blue star have never seen, but red ones
often In case OF these two stars is white and
the other blush Most Of these stars can be plainly
through very small glasses. and indeed much OF
work In this branch OF science has been done wtn
such glasses An English astronomer used book
cover rolled up, with glasses placed In the ends This
was Newton and the glass still preserved. double
star is two close together, each usually Of different
tint One color generally the complementary color OF
the other have tried to match these shades OF color
with worsted, but nothing comes near them except
| rubies and diamonds.
THE sPECTRosCoPE AND THE TRANSIT OF VENUS.
Into every branch OF physical research comes the
specroscope As geologist with his hammer breaks
UP the rocks OF earth and determines their compositions
so with the spectroscope the astronomer breaks tho
light proceeding from the heavenly bodies, and shows is
in the coors OF the spectrum The spectrum Is
crossed intervals by dark lines which were known as
far back as 1874 the real nature of which was not
discovered until quite recently. With the prism OF the
pectroscope is possible to refract not only the light
but also that from the stars and TO obtain
the specra Of the latter bodies. Astronomical inVest
cations have Of late become much more refined The
power Of telescope has been much increased, but
this has rendered Lecessary corresponding
refinement In the clearness OF the atmosphere aud tho
cockwork employed in measuring the intervals OF tie'
With these, however great progress has been made H
is now shown that the same elements-such as IRON.
sodium, well others-are In the constitution Oh the
sun aud OF the earth.
One of the earliest Of dscoverers in this field was fa
ther secchi an Italian who proclaimed these truths Of
astronomy Rome, where not very many years before
Gaeo suffered daring to proclaim the result
of his abors the field In spite OF the decline OF
Papa power the Eternal City the period OF the for
mers fnyestiga aton the Holy Father still ruled in
things as learned when at Rome many years ago.
remember that when desired to visit the observatory
that place ignorant OF the ways of Popes and
Cardinals not to know that its sacred doors were
closed to the entrance OF those OF my sex.
The speaker gave account OF her visit TO the obser
vatory, which she entered alone not being allowed to
have female servant accompany her. She spoke in
emphatic Of the clearness of the atmosphere at
Rome saying that it wonder that with such
air Calico accomplished so much with inadequate
aceorSng so FsthSr oceh Belongs to group Of starr;
In the measurement of the distance between the earth
and the heavenly bodies astronomers were 1900 years
III nDdng the distance OF star The star selected fr
tins purpose was u Cygn because 1t nearer the earth
than ~ any Of the fixed tsa stars. great step
in England, when. in the time OF Henry
determined to constitute an inch Once having unit
OF measurement We can measure anything. The dis
tance Of the the earth found OF the
planet Venus At certain periods the latter comes be-
tween us ana the sun. and such time Is chosen for
the planet which we see turned away from the sun ap
pears dark circle the surface OF the latter The
process OF measurement Is difficult to explain q
he sun enIigbtens the earth AthonSb the distance of
omers yet they are all on the alert for the transit OF
Venus to take place 1884, by Of which they may
be able TO verify former observations
The speaker then went ON TO give the method OF de-
termnng the distance OF the stars by their annual para
lax She then spoke of the time required the passage
OF light from various stars rays rom the polar
reaching 80 years its emission. she explained
the variable stars those which differ in splendOr
rous times. One OF these in the Great Bear has
period Of variation 3O days Other variable
greater or smaller periods OF variation interest
in the variable stars is awakened By the knowledge
the fact that Is itself variable The
spots have been noticed in great numbers during
past few years The quantity OF light which receive
during the time when the suns disc thus obscured is
less than usual yet We do not perceive tie difference.
Or late years has been noticed that the spots
have some connection with certain conditions OF tho
planets. Venus In OF It's positions influences them
ye yet imagination is often OF great service TO the sci
music OF the spheres lie would have discovered
Rhythmic motion Of the heavenly bodies.
woMAS's WORK ASTRONOMY
The speaker then account OF the measurement
Of double stars exceedingly delicate work. speak
ing Sir william Hersches labors this field she said
he assisted by his sister, Miss Caroline HerscLewho
night after night patiently worked recording what her
brother Her history is that of many another wo
caring nothing for her fame and striving to
build up that Of her brother. To do this work she re-
qured combination Of Qualities not often possstsed by
woman. 1t was greatly owing to her that Hersehels
was appreciated! We are brought up to think too
highly Of George III iet however, Judge him too
he gave her position in the Royal Observatory and
when he found that she doing mans labor he gave
Present stage Of progressi lLaughter.l
When recall the yigor of Mary sonervilIe ask the
the e their own aSors S1d Se heap
that young women are dwarfed BY hard study, but my
years IN college show me that study good Mary
sOmeryile genius After pursuing her studies for
time, she CAME out in society IN Edinburgh where
she advised t. conceal her studies In spite OF
modesy aud her friends caution. her gifts were dscov
cred Perhaps her first great work her translation
OF La Place. 10 shown To Sir John Hersohcl, who
looked over IT, and characterized great work My