PAPERSSCIENCE THE DENVER ECLIPSE COLORS OF STARS
“The dissemination of information
in regard to science and to scientific investigations
relieves the scientist from the small annoyances of
extreme ignorance.
“No one to-day will expect to
receive a letter such as reached Sir John Herschel
some years ago, asking for the writer’s horoscope
to be cast; or such as he received at another time,
which asked, Shall I marry? and Have I seen her?
“Nor can it be long, if the
whole population is somewhat educated, that I shall
be likely to receive, as I have done, applications
for information as to the recovery of stolen goods,
or to tell fortunes.
“When crossing the Atlantic,
an Irish woman came to me and asked me if I told fortunes;
and when I replied in the negative, she asked me if
I were not an astronomer. I admitted that I made
efforts in that direction. She then asked me
what I could tell, if not fortunes. I told her
that I could tell when the moon would rise, when the
sun would rise, etc. She said, ‘Oh,’
in a tone which plainly said, ‘Is that
all?’
“Only a few winters since, during
a very mild winter, a young lad who was driving a
team called out to me on the street, and said he had
a question to ask me.
“I stopped; and he asked, ‘Shall
we lose our ice-crop this winter?’
“It was January, and it was
New England. It took very little learning and
no alchemy to foretell that the month of February and
the neighborhood of Boston would give ice enough;
and I told him that the ice-crop would be abundant;
but I was honest enough to explain to him that my
outlook into the future was no better than his.
“One of the unfavorable results
of the attempt to popularize science is this:
the reader of popular scientific books is very likely
to think that he understands the science itself, when
he merely understands what some writer says about
science.
“Take, for example, the method
of determining the distance of the moon from the earthone
of the easiest problems in physical astronomy.
The method can be told in a few sentences; yet it
took a hundred years to determine it with any degree
of accuracyand a hundred years, not of
the average work of mankind in science, but a hundred
years during which able minds were bent to the problem.
“Still, with all the school-masters,
and all the teaching, and all the books, the ignorance
of the unscientific world is enormous; they are ignorant
both waysthey underrate the scientific
people and they overrate them. There is, on the
one hand, the Irish woman who is disappointed because
you cannot tell fortunes, and, on the other hand,
the cultivated woman who supposes that you must know
all science.
“I have a friend who wonders
that I do not take my astronomical clock to pieces.
She supposes that because I am an astronomer, I must
be able to be a clock-maker, while I do not handle
a tool if I can help it! She did not expect to
take her piano to pieces because she was musical!
She was as careful not to tinker it as I was not to
tinker the clock, which only an expert in clock-making
was prepared to handle.
“... Only a few weeks since
I received a letter from a lady who wished to come
to make me a visit, and to ‘scan the heavens,’
as she termed it. Now, just as she wrote, the
clock, which I was careful not to meddle with, had
been rapidly gaining time, and I was standing before
it, watching it from hour to hour, and slightly changing
its rate by dropping small weights upon its pendulum.
Time is so important an element with the astronomer,
that all else is subordinate to it.
“Then, too, the uneducated assume
the unvarying exactness of mathematical results; while,
in reality, mathematical results are often only approximations.
We say the sun is 91,000,000 miles from the earth,
plus or minus a probable error; that is, we are right,
probably, within, say, 100,000 miles; or, the sun
is 91,000,000 minus 100,000 miles, or it is 91,000,000
plus 100,000 miles off; and this probable error is
only a probability.
“If we make one more observation
it cannot agree with any one of our determinations,
and it changes our probable error.
“This ignorance of the masses
leads to a misconception in two ways; the little that
a scientist can do, they do not understand,they
suppose him to be godlike in his capacity, and they
do not see results; they overrate him and they underrate
himthey underrate his work.
“There is no observatory in
this land, nor in any land, probably, of which the
question is not asked, ’Are they doing anything?
Why don’t we hear from them? They should
make discoveries, they should publish.’
“The one observation made at
Greenwich on the planet Neptune was not published
until after a century or moreit was recorded
as a star. The observation had to wait a hundred
years, about, before the time had come when that evening’s
work should bear fruit; but it was good, faithful
work, and its time came.
“Kepler was years in passing
from one of his laws to another, while the school-boy,
to-day, rattles off the three as if they were born
of one breath.
“The scientist should be free
to pursue his investigations. He cannot be a
scientist and a school-master. If he pursues his
science in all his intervals from his class-work,
his classes suffer on account of his engrossments;
if he devotes himself to his students, science suffers;
and yet we all go on, year after year, trying to work
the two fields together, and they need different culture
and different implements.
“1878. In the eclipse of
this year, the dark shadow fell first on the United
States thirty-eight degrees west of Washington, and
moved towards the south-east, a circle of darkness
one hundred and sixteen miles in diameter; circle
overlapping circle of darkness until it could be mapped
down like a belt.
“The mapping of the dark shadow,
with its limitations of one hundred and sixteen miles,
lay across the country from Montana, through Colorado,
northern and eastern Texas, and entered the Gulf of
Mexico between Galveston and New Orleans. This
was the region of total eclipse. Looking along
this dark strip on the map, each astronomer selected
his bit of darkness on which to locate the light of
science.
“But for the distance from the
large cities of the country, Colorado seemed to be
a most favorable part of the shadow; it was little
subject to storms, and reputed to be enjoyable in
climate and abundant in hospitality.
“My party chose Denver, Col.
I had a friend who lived in Denver, and she was visiting
me. I sought her at once, and with fear and trembling
asked, ’Have you a bit of land behind your house
in Denver where I could put up a small telescope?’
‘Six hundred miles,’ was the laconic reply!
“I felt that the hospitality
of the Rocky mountains was at my feet. Space
and time are so unconnected! For an observation
which would last two minutes forty seconds, I was
offered six hundred miles, after a journey of thousands.
“A journey from Boston to Denver
makes one hopeful for the future of our country.
We had hour after hour and day after day of railroad
travel, over level, unbroken land on which cattle
fed unprotected, summer and winter, and which seemed
to implore the traveller to stay and to accept its
richness. It must be centuries before the now
unpeopled land of western Kansas and Colorado can
be crowded.
“We started from Boston a party
of two; at Cincinnati a third joined us; at Kansas
City we came upon a fourth who was ready to fall into
our ranks, and at Denver two more awaited us; so we
were a party of six’All good women
and true.’
“All along the road it had been
evident that the country was roused to a knowledge
of the coming eclipse; we overheard remarks about it;
small telescopes travelled with us, and our landlord
at Kansas City, when I asked him to take care of a
chronometer, said he had taken care of fifty of them
in the previous fortnight. Our party had three
telescopes and one chronometer.
“We had travelled so comfortably
all along the Santa Fe road, from Kansas City to Pueblo,
that we had forgotten the possibility of other railroad
annoyances than those of heat and dust until we reached
Pueblo. At Pueblo all seemed to change.
We left the Santa Fe road and entered upon that of
the Rio Grande.
“Which road was to blame, it
is not for me to say, but there was trouble at once
about our ‘round-trip ticket.’ That
settled, we supposed all was right.
“In sending out telescopes so
far as from Boston to Denver, I had carefully taken
out the glasses, and packed them in my trunks.
I carried the chronometer in my hand.
“It was only five hours’
travel from Pueblo to Denver, and we went on to that
city. The trunks, for some unexplained reason,
or for no reason at all, chose to remain at Pueblo.
“One telescope-tube reached
Denver when we did; but a telescope-tube is of no
value without glasses. We learned that there was
a war between the two railroads which unite at Pueblo,
and war, no matter where or when it occurs, means
ignorance and stupidity.
“The unit of measure of value
which the railroad man believes in is entirely different
from that in which the scientist rests his faith.
“A war between two railroads
seemed very small compared with two minutes forty
seconds of observation of a total eclipse. One
was terrestrial, the other cosmic.
“It was Wednesday when we reached
Denver. The eclipse was to occur the following
Monday.
“We haunted the telegraph-rooms,
and sent imploring messages. We placed ourselves
at the station, and watched the trains as they tossed
out their freight; we listened to every express-wagon
which passed our door without stopping, and just as
we were trying to find if a telescope could be hired
or bought in Denver, the glasses arrived.
“It was now Friday; we must
put up tents and telescopes, and test the glasses.
“It rained hard on Fridaynothing
could be done. It rained harder on Saturday.
It rained hardest of all on Sunday, and hail mingled
with the rain. But Monday morning was clear and
bright. It was strange enough to find that we
might camp anywhere around Denver. Our hostess
suggested to us to place ourselves on ‘McCullough’s
Addition.’ In New York or Boston, if I
were about to camp on private grounds I should certainly
ask permission. In the far West you choose your
spot of ground, you dig post-holes and you pitch tents,
and you set up telescopes and inhabit the land; and
then the owner of the land comes to you, and asks if
he may not put up a fence for you, to keep off intruders,
and the nearest residents come to you and offer aid
of any kind.
“Our camping-place was near
the house occupied by sisters of charity, and the
black-robed, sweet-faced women came out to offer us
the refreshing cup of tea and the new-made bread.
“All that we needed was ‘space,’
and of that there was plenty.
“Our tents being up and the
telescopes mounted, we had time to look around at
the view. The space had the unlimitedness that
we usually connect with sea and sky. Our tents
were on the slope of a hill, at the foot of which
we were about six thousand feet above the sea.
The plain was three times as high as the hills of
the Hudson-river region, and there arose on the south,
almost from west to east, the peaks upon peaks of
the Rocky mountains. One needs to live upon such
a plateau for weeks, to take in the grandeur of the
panorama.
“It is always difficult to teach
the man of the people that natural phenomena belong
as much to him as to scientific people. Camping
parties who put up telescopes are always supposed
to be corporations with particular privileges, and
curious lookers-on gather around, and try to enter
what they consider a charmed circle. We were remarkably
free from specialists of this kind. Camping on
the south-west slope of the hill, we were hidden on
the north and east, and another party which chose the
brow of the hill was much more attractive to the crowd.
Our good serving-man was told to send away the few
strollers who approached; even our friends from the
city were asked to remove beyond the reach of voice.
“There is always some one to
be found in every gathering who will not submit to
law. At the time of the total eclipse in Iowa,
in 1869, there passed in and out among our telescopes
and observers an unknown, closely veiled woman.
The remembrance of that occasion never comes to my
mind without the accompaniment of a fluttering green
veil.
“This time it was a man.
How he came among us and why he remained, no one can
say. Each one supposed that the others knew, and
that there was good reason for his presence.
If I was under the tent, wiping glasses, he stood
beside me; if the photographer wished to make a picture
of the party, this man came to the front; and when
I asked the servant to send off the half-vagrant boys
and girls who stood gazing at us, this man came up
and said to me in a confidential tone, ’They
do not understand the sacredness of the occasion,
and the fineness of the conditions.’ There
was something regal in his audacity, but he was none
the less a tramp.
“Persons who observe an eclipse
of the sun always try to do the impossible. They
seem to consider it a solemn duty to see the first
contact of sun and moon. The moon, when seen in
the daytime, looks like a small faint cloud; as it
approaches the sun it becomes wholly unseen; and an
observer tries to see when this unseen object touches
the glowing disc of the sun.
“When we look at any other object
than the sun, we stimulate our vision. A good
observer will remain in the dark for a short time before
he makes a delicate observation on a faint star, and
will then throw a cap over his head to keep out strong
lights.
“When we look at the sun, we
at once try to deaden its light. We protect our
eyes by dark glassesthe less of sunlight
we can get the better. We calculate exactly at
what point the moon will touch the sun, and we watch
that point only. The exact second by the chronometer
when the figure of the moon touches that of the sun,
is always noted. It is not only valuable for
the determination of longitude, but it is a check on
our knowledge of the moon’s motions. Therefore,
we try for the impossible.
“One of our party, a young lady
from California, was placed at the chronometer.
She was to count aloud the seconds, to which the three
others were to listen. Two others, one a young
woman from Missouri, who brought with her a fine telescope,
and another from Ohio, besides myself, stood at the
three telescopes. A fourth, from Illinois, was
stationed to watch general effects, and one special
artist, pencil in hand, to sketch views.
“Absolute silence was imposed
upon the whole party a few minutes before each phenomenon.
“Of course we began full a minute
too soon, and the constrained position was irksome
enough, for even time is relative, and the minute of
suspense is longer than the hour of satisfaction.
“The moon, so white in the sky,
becomes densely black when it is closely ranging with
the sun, and it shows itself as a black notch on the
burning disc when the eclipse begins.
“Each observer made her record
in silence, and then we turned and faced one another,
with record in handwe differed more than
a second; it was a large difference.
“Between first contact and totality
there was more than an hour, and we had little to
do but look at the beautiful scenery and watch the
slow motion of a few clouds, on a height which was
cloud-land to dwellers by the sea.
“Our photographer begged us
to keep our positions while he made a picture of us.
The only value to the picture is the record that it
preserves of the parallelism of the three telescopes.
You would say it was stiff and unnatural, did you
not know that it was the ordering of Nature herselfthey
all point to the centre of the solar system.
“As totality approached, all
again took their positions. The corona, which
is the ‘glory’ seen around the sun, was
visible at least thirteen minutes before totality;
each of the party took a look at this, and then all
was silent, only the count, on and on, of the young
woman at the chronometer. When totality came,
even that ceased.
“How still it was!
“As the last rays of sunlight
disappeared, the corona burst out all around the sun,
so intensely bright near the sun that the eye could
scarcely bear it; extending less dazzlingly bright
around the sun for the space of about half the sun’s
diameter, and in some directions sending off streamers
for millions of miles.
“It was now quick work.
Each observer at the telescopes gave a furtive glance
at the un-sunlike sun, moved the dark eye-piece from
the instrument, replaced it by a more powerful white
glass, and prepared to see all that could be seen
in two minutes forty seconds. They must note
the shape of the corona, its color, its seeming substance,
and they must look all around the sun for the ‘interior
planet.’
“There was certainly not the
beauty of the eclipse of 1869. Then immense radiations
shot out in all directions, and threw themselves over
half the sky. In 1869, the rosy prominences were
so many, so brilliant, so fantastic, so weirdly changing,
that the eye must follow them; now, scarcely a protuberance
of color, only a roseate light around the sun as the
totality ended. But if streamers and prominences
were absent, the corona itself was a great glory.
Our special artist, who made the sketch for my party,
could not bear the light.
“When the two minutes forty
seconds were over, each observer left her instrument,
turned in silence from the sun, and wrote down brief
notes. Happily, some one broke through all rules
of order, and shouted out, ‘The shadow! the
shadow!’ And looking toward the southeast we
saw the black band of shadow moving from us, a hundred
and sixty miles over the plain, and toward the Indian
Territory. It was not the flitting of the closer
shadow over the hill and dale: it was a picture
which the sun threw at our feet of the dignified march
of the moon in its orbit.
“And now we looked around.
What a strange orange light there was in the north-east!
what a spectral hue to the whole landscape! Was
it really the same old earth, and not another planet?
“Great is the self-denial of
those who follow science. They who look through
telescopes at the time of a total eclipse are martyrs;
they severely deny themselves. The persons who
can say that they have seen a total eclipse of the
sun are those who rely upon their eyes. My aids,
who touched no glasses, had a season of rare enjoyment.
They saw Mercury, with its gleam of white light, and
Mars, with its ruddy glow; they saw Regulus come out
of the darkening blue on one side of the sun, Venus
shimmer and Procyon twinkle near the horizon, and Arcturus
shine down from the zenith.
“We saw the giant shadow
as it left us and passed over the lands of
the untutored Indian; they saw it as it approached
from the distant west, as it fell upon the peaks of
the mountain-tops, and, in the impressive stillness,
moved directly for our camping-ground.
“The savage, to whom it is the
frowning of the Great Spirit, is awe-struck and alarmed;
the scholar, to whom it is a token of the inviolability
of law, is serious and reverent.
“There is a dialogue in some
of the old school-readers, and perhaps in some of
the new, between a tutor and his two pupils who had
been out for a walk. One pupil complained that
the way was long, the road was dusty, and the scenery
uninteresting; the other was full of delight at the
beauties he had found in the same walk. One had
walked with his eyes intellectually closed; the other
had opened his eyes wide to all the charms of nature.
In some respects we are all, at different times, like
each of these boys: we shut our eyes to the enjoyments
of nature, or we open them. But we are capable
of improving ourselves, even in the use of our eyeswe
see most when we are most determined to see. The
will has a wonderful effect upon the perceptive
faculties. When we first look up at the myriads
of stars seen in a moonless evening, all is confusion
to us; we admire their brilliancy, but we scarcely
recognize their grouping. We do not feel the
need of knowing much about them.
“A traveller, lost on a desert
plain, feels that the recognition of one star, the
Pole star, is of itself a great acquisition; and all
persons who, like mariners and soldiers, are left
much with the companionship of the stars, only learn
to know the prominent clusters, even if they do not
know the names given to them in books.
“The daily wants of the body
do not require that we should say
“’Give me the ways of wandering
stars to know
The depths of heaven above
and earth below.’
But we have a hunger of the mind which
asks for knowledge of all around us, and the more
we gain, the more is our desire; the more we see, the
more are we capable of seeing.
Besides learning to see, there is another art to be
learned,not to
see what is not.
“If we read in to-day’s
paper that a brilliant comet was seen last night in
New York, we are very likely to see it to-night in
Boston; for we take every long, fleecy cloud for a
splendid comet.
“When the comet of 1680 was
expected, a few years ago, to reappear, some young
men in Cambridge told Professor Bond that they had
seen it; but Professor Bond did not see it. Continually
are amateurs in astronomy sending notes of new discoveries
to Bond, or some other astronomers, which are no discoveries
at all!
“Astronomers have long supposed
the existence of a planet inferior to Mercury; and
M. Leverrier has, by mathematical calculation, demonstrated
that such a planet exists. He founded his calculations
upon the supposed discovery of M. Lesbarcault, who
declares that it crossed the sun’s disc, and
that he saw it and made drawings. The internal
evidence, from the man’s account, is that he
was an honest enthusiast. I have no doubt that
he followed the path of a solar spot, and as the sun
turned on its axis he mistook the motion for that
of the dark spot; or perhaps the spot changed and
became extinct, and another spot closely resembling
it broke out and he was deceived; his wishes all the
time being ’father to the thought.’
“The eye is as teachable as
the hand. Every one knows the most prominent
constellations,the Pleiades, the Great
Bear, and Orion. Many persons can draw the figures
made by the most brilliant stars in these constellations,
and very many young people look for the ‘lost
Pleiad.’ But common observers know these
stars only as bright objects; they do not perceive
that one star differs from another in glory; much less
do they perceive that they shine with differently
colored rays.
“Those who know Sirius and Betel
do not at once perceive that one shines with a brilliant
white light and the other burns with a glowing red,
as different in their brilliancy as the precious stones
on a lapidary’s table, perhaps for the same
reason. And so there is an endless variety of
tints of paler colors.
“We may turn our gaze as we
turn a kaleidoscope, and the changes are infinitely
more startling, the combinations infinitely more beautiful;
no flower garden presents such a variety and such delicacy
of shades.
“But beautiful as this variety
is, it is difficult to measure it; it has a phantom-like
intangibilitywe seem not to be able to
bring it under the laws of science.
“We call the stars garnet and
sapphire; but these are, at best, vague terms.
Our language has not terms enough to signify the different
delicate shades; our factories have not the stuff whose
hues might make a chromatic scale for them.
“In this dilemma, we might make
a scale of colors from the stars themselves.
We might put at the head of the scale of crimson stars
the one known as Hind’s, which is four degrees
west of Rigel; we might make a scale of orange stars,
beginning with Betel as orange red; then we should
have
Betelgeuze, Aldebaran, ss Ursae
Minoris, Altair and a Canis, a
Lyrae,
the list gradually growing paler and
paler, until we come to a Lyrae, which might be the
leader of a host of pale yellow stars, gradually fading
off into white.
“Most of the stars seen with
the naked eye are varieties of red, orange, and yellow.
The reds, when seen with a glass, reach to violet or
dark purple. With a glass, there come out other
colors: very decided greens, very delicate blues,
browns, grays, and white. If these colors are
almost intangible at best, they are rendered more so
by the variations of the atmosphere, of the eye, and
of the glass. But after these are all accounted
for, there is still a real difference. Two stars
of the class known as double stars, that is, so little
separated that considerable optical power is necessary
to divide them, show these different tints very nicely
in the same field of the telescope.
“Then there comes in the chance
that the colors are complementary; that the eye, fatigued
by a brilliant red in the principal star, gives to
the companion the color which would make up white
light. This happens sometimes; but beyond this
the reare innumerable cases of finely contrasted colors
which are not complementary, but which show a real
difference of light in the stars; resulting, perhaps,
from distance,for some colors travel farther
than others, and all colors differ in their order
of march,perhaps from chemical differences.
“Single blue or green stars
are never seen; they are always given as the smaller
companion of a pair.
“Out of several hundred observed
by Mr. Bishop, forty-five have small companions of
a bluish, or greenish, or purplish color. Almost
all of these are stars of the eighth to tenth magnitude;
only once are both seen blue, and only in one case
is the large one blue. In almost every case the
large star is yellow. The color most prevailing
is yellow; but the varieties of yellow are very great.
“We may assume, then, that the
blue stars are faint ones, and probably distant ones.
But as not all faint stars or distant ones are blue,
it shows that there is a real difference. In
the star called 35 Piscium, the small star shows a
peculiar snuffy-brown tinge.
“Of two stars in the constellation
Ursa Minoris, not double stars, one is orange and
the other is green, both very vivid in color.
“From age to age the colors
of some prominent stars have certainly changed.
This would seem more likely to be from change of place
than of physical constitution.
“Nothing comes out more clearly
in astronomical observations than the immense activity
of the universe. ’All change, no loss, ’tis
revolution all.’
“Observations of this kind are
peculiarly adapted to women. Indeed, all astronomical
observing seems to be so fitted. The training
of a girl fits her for delicate work. The touch
of her fingers upon the delicate screws of an astronomical
instrument might become wonderfully accurate in results;
a woman’s eyes are trained to nicety of color.
The eye that directs a needle in the delicate meshes
of embroidery will equally well bisect a star with
the spider web of the micrometer. Routine observations,
too, dull as they are, are less dull than the endless
repetition of the same pattern in crochet-work.
“Professor Chauvenet enumerates
among ‘accidental errors in observing,’
those arising from imperfections in the senses, as
’the imperfection of the eye in measuring small
spaces; of the ear, in estimating small intervals
of time; of the touch, in the delicate handling of
an instrument.’
“A girl’s eye is trained
from early childhood to be keen. The first stitches
of the sewing-work of a little child are about as good
as those of the mature man. The taking of small
stitches, involving minute and equable measurements
of space, is a part of every girl’s training;
she becomes skilled, before she is aware of it, in
one of the nicest peculiarities of astronomical observation.
“The ear of a child is less
trained, except in the case of a musical education;
but the touch is a delicate sense given in exquisite
degree to a girl, and her training comes in to its
aid. She threads a needle almost as soon as she
speaks; she touches threads as delicate as the spider-web
of a micrometer.
“Then comes in the girl’s
habit of patient and quiet work, peculiarly fitted
to routine observations. The girl who can stitch
from morning to night would find two or three hours
in the observatory a relief.”