The Burnham Telescope | Wisconsin Public Television

The Burnham Telescope

The Burnham Telescope

Record date: Jan 09, 2018

Jim Lattis, Director of UW Space Place, discusses the history of Sherburne W. Burnham’s telescope, a 6-inch refractor telescope built in 1870. Lattis documents the locations around the country and around the world where the telescope was set up to view double stars and eclipses.

University Place Campus: 

University Place Lecture Series: 

University Place Subjects: 

Episode Transcript

- Good evening and welcome

to UW Space Place tonight.

Our talk tonight is

on a historical topic.

I've been working a

bit on the history

of Washburn Observatory and

the various, part of that

is the various telescopes

and instruments that we have

that have been associated

with Washburn Observatory.

And one that turns out to

be of particular interest

is a telescope called

the Burnham telescope.

Which it turns out is a

very well-traveled telescope

with a very complicated but

scientifically important

history, so I thought I

would talk a little bit about

the Burnham Telescope.

It's one, as many

of you will know,

of a number of famous telescopes

in southern Wisconsin.

We have the 15 and 1/2-inch telescope

at Washburn Observatory.

Probably most famous

is the world's largest

refracting telescope

in Yerkes Observatory

down in Williams Bay.

And I'm gonna talk about

a much smaller telescope.

Instead of a 15 and 1/2-inch telescope

or a 40-inch telescope, this

is a six-inch telescope.

But this six-inch telescope

has some very important

historical significance

and is a pretty

interesting instrument.

All of those telescopes

that I'm talking about there

are of particular

category of telescopes

that are not very commonly

used, in fact basically

never used in modern

astronomical research.

Modern telescopes, when you

think of a big observatory,

typically the telescope

that is gonna be

the biggest telescope

at an observatory,

or even the medium sized ones,

are reflecting telescopes.

But research telescopes

were refracting telescopes

for a very long time,

really from Galileo,

for a few centuries.

And those telescopes

use a lens at the front

of the telescopes to collect

light and form an image.

And they became really

important research telescopes

in the, or they took the

form of a modern refractor

as a research telescope

in the early 1800s.

In order for that to happen

they had to overcome a problem.

The telescope that Galileo

had, and many generations,

a few generations of

astronomers afterwards,

the telescopes that

they used a simple lens,

which you can see up at

the top diagram there.

A simple lens to bring the

rays of light together to form

an image, but they had

something called a color error.

Which is more technically

called chromatic aberration.

But color error tells you

what that actually means.

The lenses couldn't

form a single image

from all the different

wavelengths of light,

essentially the

different colors.

So the blue image formed at

a slightly different place

from the green image,

a different place

from the red image.

And so you never

got a perfect image

with a simple

refracting telescope.

This problem was

solved in the mid-1700s

by the type of lens that

you see on the right

and halfway down there,

combining two lenses,

which have

cross-sections like that.

Combining two lenses

that are made of

different optical

kinds of glass,

glass with different

optical properties,

usually called crown and

flint as it's labeled there.

Chemically different glasses,

they have different

indices of refraction.

If you do this right you

can make that color error

not quite disappear but you

can improve it enormously

to the point where you

get a very good image.

And you see that happening

there on the right.

This kind of telescope

needs a lens,

needs a perfectly

clear disk of glass

to make a lens out of.

And if you've got two

lenses, if it's a double

then you need two

perfect disks of glass.

So the other problem

that had to be dealt with

was making optically

perfect disks of glass.

And that was another technical

problem that had to be solved

in addition to the optical

problem of shaping the lenses.

But all of these things came together in the early 1800s

and the modern refracting

research telescope took shape.

And it usually is identified

with Joseph Fraunhofer,

the German telescope maker.

And even with this particular

telescope that you see there

which was a nine-inch, that's

the diameter of the lens,

a nine-inch lens, which

is huge for that time,

in about 1826, that he made

for the Dorpat Observatory,

which is in modern day Estonia.

And that telescope is optically

like many generations of it,

including the Burnham telescope

that we're talk about.

And it's also very similar

in terms of its mounting.

Fraunhofer started making

a telescope mounting

that became standard,

and because he was German

this is often called a

German telescope mount,

German equatorial mount,

and you kind of see it there.

I'm not gonna talk in too

much detail about that

but that general configuration,

that's probably what you

think of if you think of

a cartoon image of what an

astronomer is looking at,

looking through, it's a

telescope something like that.

And that's because this

telescope set the pattern

for many, many years, until

the early 20th century really,

for research telescopes.

And it was a very, very

popular type of telescope.

Well the Burnham telescope

is exactly one of those.

It follows on the Fraunhofer

pattern, going back then for

quite a few years before this

telescope came to be in 1870.

It's called the

Burnham telescope

because of the

guy who bought it,

which is Sherburne W.

Burnham, who you see there.

Burnham was an amateur

astronomer really

all of his life

in the sense that he

basically always had a career

that was not astronomical.

He was a stenographer,

he was a partner.

This was in the days

when to be a stenographer

you apprenticed, it was a little

bit like becoming a lawyer.

You apprenticed with

a master stenographer

and you might form a firm,

and Burnham was a member

of a firm in Chicago,

a stenographer's firm.

So if you needed

somebody to take letters

and write out letters

for you in the days

before typewriters, you

would hire a stenographer.

And Burnham was one of

these, and must have been

doing pretty well

financially because

as he got interested in

astronomy as a hobby,

and he had been interested

in astronomy as a hobby

for quite a few years,

he decided to buy

for the time a fairly

expensive telescope.

He decided to buy a

six-inch Clark telescope.

Now Clark, Alvan Clark & Sons,

is one of the most famous

names in telescope making.

And they specialized in

these classical refractors

on the Fraunhofer pattern.

And there you see Alvan

Clark on the right.

It happened that

Alvan Clark was,

they're based in

Massachusetts, but he had

come out to the Midwest in 1869

to observe a solar

eclipse in Iowa.

And on his way back he

passed through Chicago,

and in Chicago was one

of the largest telescopes

he had made up to that point,

the 18 and 1/2-inch

telescope that the old

University of Chicago

had at the time,

which was called the

Dearborn telescope,

the Dearborn Observatory.

Confusingly, it has nothing

to do with Dearborn, Michigan.

The Dearborn telescope is an

18 and 1/2-inch telescope

that Clark had installed

there a few years before that.

And Burnham made a

point to meet with Clark

on that occasion when

Clark was in Chicago.

Had a conversation

with him about

what kind of telescope he

wanted, and ended up ordering

a telescope at that

point from Clark.

And I've got the-- I'm quoting

Burnham here, "Stipulating

only that its definition

"should be as perfect

as they could make it,"

meaning at the Clark

firm, "so as to achieve

"optimal performance

given the aperture."

It's not a huge telescope,

it's a six-inch telescope,

on double stars.

Double stars is the hobby

that Burnham had settled on.

He wanted to discover

double stars.

So he wanted a telescope

that would do this,

that would be better.

He had a couple of

previous telescopes

that had been unsatisfactory,

smaller telescopes,

three and 1/2 inch

or so, telescopes.

According to E.E. Barnard,

another famous astronomer

of the period, who was a close

friend of S.W. Burnham's,

this telescope cost $800.

So Burnham and Clark must have

agreed on the price of $800.

That'll come up again in

a few minutes, though.

And...

the basic telescope was

on an equatorial mount,

a very basic German

equatorial mount,

but without a clock drive

and without setting circles.

And we know that because

Burnham became a

little bit of a legend

in the field for managing

to improvise devices.

He improvised a clock

drive, which is the device

that keeps the

telescope axis turning

so that it will follow

an object in the sky.

It has to go at the right rate.

Burnham wrapped a rope

around the polar axle

and connected it to a weight,

and the weight sat on a bucket

of sand with a hole in it.

And so the weight

would slowly fall

and you adjust the

size of the hole

and that adjusts how fast

your telescope moves.

So he built a clock

drive for almost nothing.

So we know it was a

fairly primitive telescope

when Clark first

started using it,

when he received it

there in early 1870.

Ordered it in late 1869,

got it in early 1870.

And discovered his first

double star with that telescope

in April of 1870.

The first of many because

he would eventually discover

more than 400 double

stars with this telescope.

Which far outperformed

astronomers

with much bigger telescopes,

including the nearby

Dearborn telescope,

which was in the neighborhood,

literally in Burnham's

neighborhood in Chicago.

It was a couple blocks away.

But the astronomers over there

at the Dearborn telescope

weren't finding nearly

as many double stars,

and there were actually things

in the newspaper saying,

well this amateur Burnham

here is showing up

these astronomers who

should be working harder

over at the Dearborn

Observatory.

They've got the

bigger telescope.

But what does it mean to

discover a double star?

Basically, Burnham is

looking individually at stars,

examining stars visually,

to see whether a star that

to the eye is just one star

is really two when you

examine it with the telescope,

with enough magnification.

And so I've put up

an example up here.

In the upper center you

see the constellation Lyra,

and it has a very bright star

in it labeled Vega there.

And the star just above

Vega in that triangle there,

just above Vega, is a star

that amateur astronomers

will know as Epsilon Lyrae.

To the eye it looks

like a single star.

But if you look at it

with say binoculars,

you can see that there are

actually two stars there,

so that's a double star.

To the eye it seems like

one star, and you see a view

kind of like that on the right

where you see Vega

the brighter star,

and you see that Epsilon Lyrae

is actually two stars there.

So you can see this too.

Get out your binoculars

or a small telescope

and look at that star

and you'll see there

are really two there,

so it's a double star.

That was known long

before Burnham.

If we look at those two

stars even more carefully

here are telescopic views

of Epsilon 1 and Epsilon 2,

or 2 and 1 I guess there

are down here at the bottom.

With a bigger

telescope you can see

that there are

actually two there.

So this is a very famous sight,

very familiar sight

to stargazers,

and this is often

called the Double Double

because you see a double once,

and then when you look

at each of those stars,

you see a double twice.

So the Double Double in Lyra.

It takes a good

quality telescope

to separate those

closer pairs there.

It requires a sharp

eye from the observer

and it requires a telescope

of good optical quality,

and it requires a

good atmosphere,

what astronomers call seeing.

The air should be stable

and not blurring the images.

If you get all three of

those things then you can

separate close double stars.

Well Burnham for this

work, which is enormously,

imagine discovering 400

of these by examining one,

they're not all doubles, by

examining one after another

and looking for stars

that were not previously

known to be doubles.

Burnham's work

eventually won him

the gold medal of the

Royal Astronomical Society.

And in the speech

awarding the medal,

the president of the Royal

Astronomical Society said,

"If a star disk deviated an

almost infinitesimal quantity

"from the circular, his

eye detected it at once."

This gives you a clue about

what he's really doing.

He's not necessarily separating

every pair of double stars.

But if a star looks

just a little oblong

instead of a perfect point,

then it's probably a double.

And you can actually see

that just a little bit

in that upper image

in the middle there

that the Epsilon

Lyrae is actually

just a little bit

elongated there.

Now Burnham would go on to

use much bigger telescopes.

And eventually publish two

major double star catalogs

in 1900 and 1906, with thousands

of double stars in them.

So he was really the

giant in this field

right around the late 1800s, very early 1900s.

And...

he got his start with

the Burnham telescope

and that was why it

was famous at first,

because of the double star work that Burnham had done with it.

In order to discover

double stars,

there's no point in

discovering a double star

that's already known, and

so Burnham needed to know

as he explored the sky,

which stars that he found to

be double were already known

to be double, and which

were actual discoveries.

Well you need a star

catalog for that.

Burnham had access

to the star catalogs

over at the Dearborn

Observatory,

but nobody had a complete set

of all the double star catalogs

that had been published

over the years.

And so he took the

opportunity to visit--

on his business travels mostly--

to visit other observatories.

And at...

And at the US Naval Observatory,

which he visited in 1874,

he made the acquaintance

of the director there,

Simon Newcomb.

That's Simon Newcomb

there who's telling us

what life was like in the

19th century there, I think.

But he also met

Newcomb's second,

really his assistant at

the Naval Observatory,

who's name was Edward Holden,

who will come up a good

bit in our discussions.

Holden and Newcomb

at that point,

in the mid-1870s, were

already acting as consultants

for something called

the James Lick Trust.

James Lick was a wealthy,

very wealthy businessman

from San Francisco, who

left a large amount of money

for the creation

of an observatory.

And the Lick Trust,

after Lick's death,

the Lick Trust was in the

process of planning and building

this observatory, which

would eventually of course

be Lick Observatory

as we now know it.

And it was a very important

observatory, became one of

the world's most important

research telescopes.

It was also the first

mountaintop observatory.

So Newcomb and Holden were

in pretty constant contact

with the Lick Trust,

advising them on, you know,

how do you plan a

big observatory,

how do you get a big telescope,

what sort of

equipment do you need.

And they needed, the

Lick Trust that is,

needed to convince themselves,

that this site that

they had selected

at the top of Mount Hamilton,

which is sort of outside

of San Jose, California,

a little bit south

of San Francisco,

south and east of San Francisco.

That this site that had been

proposed for the building

of the observatory, Mount

Hamilton, was a good site.

A place where they

sky would be clear

and the air would be stable.

And Newcomb and Holden

recommended that

Burnham be the fellow to

go check out the site,

to do the site testing.

Now these days when you

build an observatory

that's pretty routine.

You send somebody out

to the proposed site

and they observe there to

see what the sky is like.

This was one of the first

cases that I know of

where somebody said, we'd

better check this site out.

Usually it was just, we're

gonna build the observatory

over there on the hill,

'cause that's where we've

decided to build it.

They wanted to make sure they

were choosing the right place

for this huge investment that

was going into this observatory.

So they paid Burnham.

He accepted this

kind of junket here.

Hard work, though.

$500, plus expenses.

But he also got a new

clock drive and setting

circles for his telescope.

To go spend August

through September 1879

on top of Mount Hamilton,

pretty much by himself,

camping out on the

top of the mountain.

He had a wooden shed,

a wooden lean-to

to protect the telescope and

observe double stars.

Double stars are a great test

of the stability

of the atmosphere.

If you want to test the

atmosphere you also have

to make sure that you have

a good observer using

a good instrument,

so Burnham was the perfect,

just the perfect

choice for this.

And he pronounced the site

to be an excellent site.

And packed up and

returned to Chicago

in October 1879.

So this was the first

trip, as far as I know,

of the Burnham telescope

outside of Chicago.

Pretty good trip for

those days, in 1879.

And the first of many

travels of the telescope.

Washburn Observatory enters

the picture here because

Edward Holden, who I

mentioned a moment ago,

Edward Holden came to

Madison in March of 1881

as the director of

Washburn Observatory.

But the second one,

because the first one

didn't last very long.

Our first director at

Washburn Observatory was

James Craig Washburn, Watson,

sorry, James Craig Watson.

And Watson died

after little more

than a year here

in November of 1880.

Now, he was a very important

shaper of Washburn Observatory.

I'll talk just a

little bit about that.

So he'd certainly

left his imprint here.

But he wasn't here long enough

to begin doing operations,

to begin doing any

important sort of research.

He did teach some

astronomy classes

before his sudden death,

probably from pneumonia

in November of 1880.

And Governor Washburn

recruited Edward Holden

from the Naval Observatory

to come here as director.

I mentioned Watson's impact

on Washburn Observatory.

Here's a picture

from about 1882,

an illustration from about

1882 of Washburn Observatory.

And there are two buildings,

there's the big

central building there.

There are two buildings

that are no longer there.

On the right is the

student observatory,

which James Watson built

out of his own funds.

Most everything there was built by Governor Washburn's funds.

But, Watson built a

solar observatory.

Sorry, built a

student observatory,

which you see

there on the right,

and which was there

until about 1960.

And that small dome there,

which we'll see again

in some other

photos was the place

where the Burnham telescope

would spend a good deal of time.

So Watson built

that observatory.

And the other building is

Watson's solar observatory.

The small building that

you see on the left.

The solar observatory

is interesting.

It is not there either.

The solar observatory

is an interesting,

is interesting for

a number of reasons.

I like to think of it as the

first innovative instrument

that Wisconsin became

famous for building,

many of which you can see in

our exhibits next door there.

And that instrument

was built to confirm

Watson's discovery

of the planet Vulcan.

Now some of you may have

heard of the planet Vulcan,

but it may not be the one

that you're thinking of.

Mr. Spock, right,

came from Vulcan.

But this is way

before Star Trek.

Astronomers had reason to think

that there was an

undiscovered planet

still in the solar system,

but not further out,

and there were undiscovered

planets further out.

But further in, within

the orbit of Mercury,

because Mercury itself, the

orbital motions of Mercury

weren't quite doing

what astronomers

thought it should be doing

because they were using

Newtonian physics there

and the Newtonian physics

didn't seem to work quite right.

So the logic was, well

there must be another planet

that we haven't

taken account of.

And if it were close

enough to the sun it would

be very hard to see.

And so this planet was rather

prematurely named Vulcan,

'cause it's close to the

fire, and close to the forge,

like Vulcan the Roman

god of the forge.

There was a French

astronomer who claimed

to have discovered it, who

claimed to have seen it

moving across the

disk of the sun.

And that lent a fair

bit of credibility

to this whole claim because

people expected it there

theoretically and somebody

claims to have seen it.

But it was very hard

to confirm, and so

in 1879...

there was a total solar

eclipse in the western US,

and one of the many

astronomers who went to be

in the path of totality of

that eclipse was Watson.

Watson went there with

the express intention

of using a telescope

to scan the sky

on either side of the

totally eclipsed sun.

So totality only lasts a

few minutes, but during that

few minutes he wanted to look

at the sky on either side,

because if there was a

planet close to the sun

maybe it would show up.

And in fact as it turns out,

he believed that he had in fact

seen such a planet.

In fact he was so confident

of it that he went ahead

and announced that he had in

fact discovered this planet.

You see one of the

many newspaper notices

about this big news,

that Professor Watson

has discovered this

long-sought planet

orbiting the sun,

this planet Vulcan.

Well, Watson was not

the only astronomer

in the world looking for Vulcan.

And all the rest of

them had not seen it.

So now there's a little

bit of controversy.

Watson says he saw it,

nobody else can confirm that,

and frankly people were

pretty skeptical of Watson.

Although Watson had a

fantastic reputation.

He held the world's record

for discovering asteroids.

He was a very, very

skilled observer,

and very well regarded

overall as a scientist.

Watson's reputation

is at stake here,

so he needs to confirm that his

observation was not in error

and that he actually

had seen this planet.

Well how to do that?

Watson came to

Washburn Observatory

in early 1879

as the new director here

amid all this controversy.

I'm sorry, in late

1879, early 1880,

amid all this controversy

about the eclipse.

And...

immediately planned this

very special instrument.

The idea was that

instead of waiting

for another total solar eclipse,

because they're relatively

rare and hard to get access to,

he would instead examine the

sky in either side of the sun

through a long tunnel.

And there was, going back

to Aristotle at least,

kind of a, well I can

really only call it a myth

at this point, that if you

looked through say a chimney

up at the sky, through some

kind of a long, long tube,

that you could see stars

in the daytime sky.

Now Watson never

actually writes out

exactly what his theory

of this instrument is,

but he seems to have been

working on the assumption

that this would be possible.

That with a suitable

telescope looking through

a long tunnel at a little

spot of daylight sky,

that you could see something

bright like a planet.

It's well known among

amateur astronomers

that you can see planets

in the daytime sky.

When Jupiter is bright

up in the daytime sky

you can find it, you can

point your telescope at it.

So you can see planets

in the daytime sky.

But he would have

to see something

that was about fourth magnitude.

So imagine the stars

in the Pleiades.

He would have to see

something about that

dim in the daytime sky,

not something nice and

bright like Venus or Jupiter.

He would have to have

a telescope underground

looking through a

tunnel out at the sky.

So to see how this would work,

here's an early photograph

from the western view

of the Washburn Observatory

complex, or part of it.

That's the observatory

on the hill on the right

and there's actually

a dome there,

the contrast in this old

photograph's not very good.

That's the main

observatory building,

and there's the little

solar observatory there.

Off in the distance is

what they used to call

University Hall, now

Bascom Hall, over there.

And notice that it

still has its cupola,

so this was before

the fire in 1917,

after which there was no cupola.

So we can at least

say it's this early.

So there's the

solar observatory.

In the basement of

the solar observatory

would be a telescope

looking through a tunnel

that goes up the hill.

So I've marked this up a little

bit to give you a rough idea

of how that would work.

A deep basement under

the solar observatory.

A tunnel which they actually

built, going up the hill there,

and up at the top of the

hill just above the tunnel

is a steerable mirror.

So that you can aim

it up into the sky

to reflect light down

into this telescope,

deep below in the basement of

the little solar observatory.

And that was Watson's

plan to examine the sky

on either side of the

sun to find Vulcan,

calculate its orbit, and

vindicate his discovery

of the summer of 1879.

Well as I mentioned Watson

died before he could

ever put that plan

into operation.

He built the observatory,

or at least built

the observatory building

and the tunnel,

but...

was never able to

carry this out.

Edward Holden came here in 1881

to become director of

the Washburn Observatory.

Holden knew Burnham from

the Naval Observatory

and needed to build a

staff of astronomers.

Burnham was right

there in Chicago

and so Holden convinced

Burnham to come join the staff

at Washburn Observatory

on a temporary basis

that would hopefully

become permanent.

And he said by the way, bring

along that six-inch telescope

that you've got down there.

And Burnham did,

he moved to Madison

from April to August of 1881.

Where he and Holden collaborated

using the big telescope,

using the 15 and 1/2-inch

Clark telescope,

for among other things, lots

of double star measurements.

They mounted the small

telescope, Burnham's

small telescope,

in the student observatory,

which at that point

Watson had intended to put

a telescope in there but had

never gotten around to that.

And so they mounted

the six-inch telescope

in the student observatory.

At the end of this trial period,

for reasons that are

not entirely clear,

Burnham decided not to stay on

as a permanent staff

member at Madison.

He had to make a decision because if he stayed in Madison

he was gonna lose the position

that he had in Chicago.

And for whatever reason

he moved back to Chicago

after the six months here.

But he left that nice

six-inch telescope

mounted in the student dome.

So why did he leave his

prize telescope here?

That's not at all clear.

And he never explains

at any particular point,

nor have I managed to find

it in any correspondence

exactly why he left

that telescope here.

I suspect Holden

persuaded him to do it.

But why would he do that?

Well Burnham might have

expected to come back.

Maybe he hadn't quite

made up his mind

on whether he was gonna accept

the position, if he was gonna

be back in a month after tying

up his affairs in Chicago.

Well then maybe might

as well leave it here.

Eventually it ended up being sold to the university,

so maybe he needed

the cash at the time.

At least one source

says that at this point

Burnham was tired of astronomy

and had decided to give it up.

So if that's true then

that would make sense too,

that he just, that he

would sell this telescope

to the university.

One way or another that

telescope stayed in Madison.

Very soon after this, Holden

reports to the Board of Regents

that the famous

Burnham telescope

is on loan to

Washburn Observatory.

But very shortly after

that, by January 1882,

he's convinced the

Board of Regents

to purchase the

telescope from Burnham,

and obviously Burnham

was okay with this,

for what Holden calls

the moderate sum of $1200.

And he told the board

that the telescope

had originally cost $1400.

You might remember

that E.E. Barnard

says the telescope cost $800.

Good question, where does

this discrepancy come from?

That's a big discrepancy

of dollars in those days.

And so we don't really know why.

We can guess that

Holden is making

a generous assessment

here of the improvements

that Burnham had made

to the telescope.

It did have a new clock drive

on it, it had a new mounting,

it had new setting circles.

So maybe it's that.

He also was still trying

to encourage Burnham

to come back here permanently

and join the staff,

so he was trying to

get him a good deal.

At any rate, it was easily

worth that amount of money

because this is

generally acknowledged

to be one of the

optically best telescopes

that Alvan Clark

& Sons ever made.

So $1400 maybe we could say

it had been proved, it's value

had been proved at that point

and was way over $800.

At any rate, the university

got a pretty good deal.

And so did Burnham.

And Burnham really

liked this telescope.

I mentioned that he published

two major star catalogs.

And in the 1900 star catalog,

the preface to the catalog

has a very interesting

introduction in which he

describes each of the telescopes

that he's used for

his double star work.

And when he gets to the

six-inch, he says this.

"It is hardly necessary to

say, in view of the discoveries

"made with it and

given in this catalog,

"that its performance on

the most difficult objects

"was simply perfect.

"Many of the stars discovered

with it are by no means

"easy to measure with the

largest telescopes now in use.

"Some of the most rapid

and interesting binaries

"in this catalog were

discovered with this instrument.

"It now belongs to the

Washburn Observatory

"of the University

of Wisconsin."

I don't know if you hear

that hint of regret in there.

I hear a hint of

regret in there,

but I'll leave it

to you to decide.

So the telescope belonged to

the University of Wisconsin

and not by coincidence did

Edward Holden have plans for it.

Holden had decided

that he really needed

to carry out Watson's plans.

Somebody needed to

complete this instrument

and see whether

Watson's plan would work

to detect a planet like

Vulcan if it exists.

He needed, that is Holden,

needed a high-quality telescope

that was small enough to fit

in the underground chamber

in the basement there of the

little solar observatory.

And of course the

Burnham telescope

just happened to be

perfect for that.

His test, so he doesn't know

if Vulcan is there or not,

so he needs to test it

by looking at something

that he knows is there.

And so the test was

to look at the stars

of the Pleiades in the daytime.

So he set up the telescope,

he actually borrowed

a steerable mirror

to put up top there,

borrowed it from Samuel

Langley and put it

at the top of the hill

to reflect the light down

through the tunnel

in the basement of

the solar observatory

he mounted the Burnham

six-inch telescope there.

And waited until he knew

that the Pleiades would be

in the field of view of the

telescope in the daytime.

And then he checked,

and he saw nothing.

There are no stars visible

there when he knows the Pleiades

have to be in the

field of the telescope.

So if you can't see fourth

magnitude stars in the Pleiades

then you're not gonna see

a fourth magnitude planet,

which is what Watson had

reported Vulcan as being.

And so Holden concludes

that this instrument

is not going to work, and

he published an article

explaining that

in a very obscure

German astronomical journal.

And took that telescope

back out of the basement

of the solar observatory,

which was a good thing

because he also reported

that the humidity problems

were terrible, water

condensed on the lenses.

And there was an

enormous air current

that went rushing

through the tunnel,

and so the seeing was awful,

and basically this was

just going to be a mess.

So he got that

telescope out of there

and put it back in the

student observatory

where it could be

much better used.

So the Burnham telescope

has attempted to take a,

take a stab at finding Vulcan.

In that case just seeing if

the instrument would work.

But it got another crack at

Vulcan very soon afterwards

when Edward Holden

was chosen to lead

a United States government expedition to the solar eclipse

of the 6th of May, 1883.

Now this was a

total solar eclipse,

whose path crossed

the South Pacific.

So you had to get out there.

It was an expensive

proposition and the funding

basically came from

the US government

and the National

Academy of Sciences

with support from the US

Navy to get these astronomers

out to the middle

of the Pacific.

And the destination they

chose was Caroline Island

in the South Pacific.

There were a lot scientists,

not just US scientists

who were headed out there.

European parties of

scientists were headed for

Caroline Island too, it

was a common destination.

And they had many

scientific goals.

But one of those was

that Holden intended

to take the six-inch telescope

and scan the sky for Vulcan

just the way Watson

had done in 1879.

So this is a big

undertaking for this time.

So the Burnham

telescope is gonna go

way far away from Chicago.

At this point, it's left

Chicago and gone to Madison.

But now it's got to

go to New York City,

where they left on the

2nd of March, 1883,

and sailed down to Panama,

where there was still no canal.

So everybody out of the

boat and carry everything

across to the other side

of the isthmus there,

where they boarded

another boat and sailed to

basically the port of

Lima, that's Lima, Peru.

The port is called Callao.

And from there they boarded,

they met with a US Navy vessel

that loaded them up and took them out to Caroline Island

in time for the eclipse.

So they observed the

eclipse on the 6th of May

and then a few days

after the eclipse,

the Navy vessel in the

meantime had gone to Tahiti,

and then came back and

picked up the astronomers,

why hang out on Caroline Island,

came back to Caroline Island,

picked up the astronomers,

where they made

a stop at Hawaii,

and then on to San Francisco,

where they arrived as you

see there, 11 June, 1883.

And at that point Holden

must have shipped the six-inch telescope back to Madison

because he stopped

and went up to visit

the then under construction

Lick Observatory

at that point before he

came back to Madison.

So this was the enormous

loop that the Burnham

telescope made for

searching for Vulcan.

So what did the telescope

and Holden find?

Well you can probably

guess how that came out.

This is from Holden's report,

showing the Caroline

Island station

and the US astronomers'

instruments there.

It's really hard to tell,

there's very little scale there,

so it's almost impossible

to tell which of those

many telescopes is the six.

I wish I could tell you

it's a particular one there.

But it's out there somewhere

in that grouping of telescopes

waiting for the eclipse.

And, on the day of the

eclipse what Holden did

was exactly what

Watson had done before,

he prepared a chart showing

what the sky would be like

in the vicinity of the sun

at the time of totality.

So there's the totally-eclipsed sun in the middle.

This is Holden's finding chart

marked up by him by hand.

You can go see it

in the UW archives.

And you can see,

maybe just barely,

that the zones are marked out

and numbered in the margin.

So what he did was sweep

along the sky there

on either side of the

sun looking for something

that's not on the chart.

And if there was

something not on the chart

then potentially that's Vulcan.

But as he reports,

he didn't find anything

that was not on the chart.

Everything was accounted for,

so no Vulcan.

Holden's negative result was

confirmed by another astronomer

who was there, a completely

independent observer.

I mean, they knew each

other, but Johann Palisa

from the Vienna, the

Imperial Observatory,

had come to Caroline

Island as well

and was doing the same

thing, looking for Vulcan.

Palisa didn't find it either.

So Holden actually published

that as far as he's concerned

it's definitively settled

that there is no Vulcan

or any other

intra-Mercurial planet.

Now not everybody accepted that,

but that was Holden's judgment,

that there was no point

in looking for it anymore.

He did use the Burnham

telescope for what it was

already famous for,

he spent many nights

observing while they were

there in the Southern sky.

And discovered 23 new

double stars there.

So the Burnham's productivity

was far from over at that point.

There is one other eclipse

trip that I know of.

The telescope got packed up

and taken to North Carolina

in 1900 for a

total solar eclipse

by Washburn Observatory

astronomer Albert Flint.

There's no record of what Flint

did with it at the eclipse,

so I like to think that he

too was looking for Vulcan

but I don't actually know that.

And the telescope is

back in Madison now

after the 1883 eclipse.

By 1886, Edward Holden

was out of here.

He had landed the job as

director of Lick Observatory.

Actually he was hired

first as president

of the University of California

and then with the promise

that when they finished

the observatory he would

become the director.

And in his place,

the third director

of Washburn Observatory,

was George C. Comstock,

who had actually been

a student of Watson's,

he had actually come from

Michigan with Watson to Madison

and had also worked under

Holden and ultimately became

the new director of

Washburn Observatory.

And it's Comstock-- So Watson

didn't last very long at all.

Holden only a few years.

It's Comstock who actually

establishes some consistent

and important research programs

here at Wisconsin.

And he defined scientific

research programs

for each of the three

major telescopes

at Washburn Observatory.

The 15 and 1/2-inch refractor,

and a transit meridian

circle telescope

that we really

haven't talked about,

and the Burnham telescope.

He had research programs

for all three of those

that dovetail together

in an important way.

For the six-inch telescope,

well really for,

also for the meridian

circle telescope as well,

the goal was to come up with accurate star positions.

Now astronomers had been

making increasingly accurate

star charts throughout

the 19th century.

This was a major program

of 19th century astronomy

worldwide, to make accurate

measurements of the stars.

You need accurate star charts

because that's what

you measure the motion,

that's what you refer the

motion of everything else to,

comets and plants

and things like that.

But measuring star positions is a little more complicated

than it sounds, there are a

number of errors that creep in.

And two particularly

troublesome ones are

something called the

aberration of starlight,

which causes star positions

to apparently shift

a little bit,

about 20 arc seconds

during the course of a

year, in a periodic way.

And the other is the effect

of the Earth's atmosphere

on star positions, which

refraction of the light

through the atmosphere,

which tends to raise

star positions away

from the horizon.

So if you measure a star

that you think is 10 degrees

above the horizon, it's actually a little bit lower than that.

Well how much lower,

you have to understand

what the refraction is doing

in order to get a

true star position.

So Comstock came

up with another,

the second of the

Washburn Observatory's

very innovative

instrument programs,

and this one was a lot more

successful than the Watson idea.

The Comstock idea used a

devise called a Loewy prism,

which is something he put

in front of the telescope.

And you see a diagram there,

maybe you can tell

what's going on there.

There's a prism, that

triangle there is a prism

out in front of the telescope,

and the prism allows

the telescope to look in

two directions at once.

So basically you

can see two stars

at 120 degrees

separated in the sky,

a huge chunk of the sky,

but they'll both appear

in the eye piece of your

telescope side by side.

And you can measure

their separation

very accurately that way.

So if one star is high

overhead and one star

is near the horizon, then

the star low on the horizon

will have a refracted

position, and the star overhead

will have basically an

un-refracted position.

And using an instrument like

this you can measure the effect

of that refraction all the

way around the horizon.

It also works to do aberration

of starlight as well.

So we won't go into that

right now, but the point is

that with this instrument

Comstock was able

to make a study of these

two very important effects

that could be used then

to correct the positions

that were coming out of the

meridian circle telescope

just down at the other

end of the observatory.

It was the six-inch

telescope that he put

the Loewy prism on, and here

you see a picture of it.

This is the Burnham six-inch

telescope now in its new role

of doing astrometry.

That's the tube of the

telescope you see there,

and the Loewy prism is that

thing sitting out on the end

in the upper right on the

tube of the telescope there.

The telescope itself is

on the Clark mounting

and clock drive that

had belonged to Burnham.

And you can tell that it

isn't quite made for Madison

because there's actually at

the base of the telescope,

where it meets that

pedestal it's sitting on,

there are some wedges that

tip it up just a little bit.

That's 'cause we're

at 43 degrees North,

a few degrees further

North than Chicago.

So letting it sit flat

on there would not do,

you had to adjust it a

little bit with some wedges.

So that's the

Chicago mount there.

And because the telescope

is looking across

a huge arc of sky,

he had to modify the dome

of the student observatory.

Notice that telescope domes

don't normally look like that.

You usually see

a slit that opens

a little bit that

you can look through.

He modified the dome here

so that it was two shells,

each a hemisphere.

And he basically cut

the existing one in half

and built another one

outside that was larger

so the two could be overlapped.

So he could see an entire

half of the sky at once.

That's fairly unusual for

an observatory arrangement.

But that's the way

that he set it up

so that the Loewy

apparatus could be used

to measure star positions.

So Comstock was ready to do

this by the fall of 1889,

although of all things to

happen to an astronomer,

he couldn't just break an ankle

or something, he had to have

optical problems, and

he needed eye surgery

in the fall of 1889.

I'd love to talk to

some ophthalmologists

about what eye surgery

was like in 1889.

But whatever it was,

Comstock was not ready

to resume observations

until the following fall.

He was also busy

during the summer

with a lot of other things.

But he managed to

complete the observations

between about 1890 and 1892

and publish the results in 1895.

And it's this work that's

basically the final research

that the Burnham

telescope would do,

the final research program

that the Burnham telescope

would carry out.

And it's pretty important stuff

because again

we're talking 1889.

It's not just ophthalmology,

but imagine calculating,

doing the corrections

to star positions.

You do that by hand,

the math, right.

So if you've got to correct

every observation you made

for say atmospheric refraction,

first of all you want that

to be the right correction,

and it would be nice if it was

arithmetically simple to do.

And Comstock came up

through these studies

with one of the most accurate

simple rules for applying

for atmospheric both for

refraction and aberration,

so that the data reduction

would go faster in those days

before there were any

significant computing aids.

So this was significant

stuff, this was important work

for the field and was essential

even quite aside from anybody

else who's doing any work,

was essential for doing

the data reduction

to the star positions

being measured right there

at Washburn Observatory

with the meridian telescope.

So the telescope after

this, the Burnham telescope

is retired from research,

but it's not done.

It seems to have been in use.

So research is where you

usually get the good records.

If it's not

being used for research then

the records get sketchy,

but it is in the records

that the telescope underwent

a significant renovation

in 1908 when the

original wooden tube

was replaced with a steel tube.

If you weren't using

that telescope then

you wouldn't bother with that.

So, they must have been using

it in the student observatory

probably for training students.

Same thing we do with it now.

There it is after the

replacement of the wooden tube.

So that has to be after 1908,

when they did that

operation there.

And again you see it's

sitting on the Clark,

Burnham's Clark mounting

and maybe you can see it

wedged up a little

bit better there.

And now we jump a bit.

The telescope was still

in use by the 1920s

when Comstock had

retired and was succeeded

by the director,

Professor Joel Stebbins,

became director of

Washburn Observatory.

And Stebbins wanted

a new mounting

for the 15 and 1/2-inch telescope, for

the big telescope.

And the plan he settled on was

to have the university shops

build this new mounting,

which was gonna be expensive.

So he wanted to make sure

the design would work well,

so he had a small one made,

basically a prototype,

made in the university shops.

And the six-inch was remounted

on this new mounting,

which was designed by a

fellow named Oscar Romare,

and a machinist, M.H. Kidder,

of the UW Machine Shops.

So they created

this new mounting

and mounted the six-inch telescope on it.

And basically proved that

the prototype would work

so that they got the confidence to go on with the bigger one.

And the Wisconsin engineer

was quite enthusiastic

about this telescope mounting,

by far the most elaborately

equipped instrument

of its size in the world, they

perhaps hyperbolically said.

But it was pretty

advanced for its day.

A new clock drive

and setting circles

that you didn't have to

climb up on a ladder to read,

and electric controls from

the end of the telescope,

rather than having to pull

ropes and climb on ladders.

So this was a

significant advance,

this new mounting.

At this point, what happens

to the old mounting?

Well it goes into the basement

at Washburn Observatory

where the wooden tube probably

already was by this time.

And we get a clue

about that in 1927

the American

Astronomical Society

for the first time

met in Madison.

And the accounts

of the meeting say

that the Burnham telescope,

the old Burnham telescope,

the historic Burnham telescope was on display for the meeting.

And we see that in

this group photo.

So I've identified a

few of the people there,

the J.S., that's Joel Stebbins,

and G.C. just to the right,

that's George Comstock

his predecessor.

So this is the group

portrait from the conference

outside of the east entrance

of Washburn Observatory,

and notice what looks

like a stovepipe

on the ground down in front

there, that's the tube,

the original wooden tube

of the Burnham telescope

that got trotted out for this

historical appearance here.

The mounting was probably

too big and heavy to drag

out on to the lawn there.

And that's Joel

Stebbins' dog Tiko.

I'm guessing there's a ham sandwich just inside that tube.

(laughter)

Now one other person that

attended this meeting

is Philip Fox, P.F. up there.

Philip Fox at that

time was the director

of the Dearborn Observatory,

which was by then at

Northwestern University.

Fox was here.

And...

Fox became the first director

of the Adler Planetarium.

Now by this time the

Burnham telescope had been

replaced on that new mounting

with a new telescope,

which is what Stebbins

actually had in mind all along

was to get a new

larger telescope.

And that mounting that

was made for the six-inch

basically tested by

this time the telescope,

the whole telescope

is in storage,

along with the original mounting

and along with the

original wooden tube.

The Adler Planetarium

even from its very earliest,

even before it opened,

the plan was that it would

have historical instrument

exhibits as well as be a

planetarium sort of thing.

And so Philip Fox who

had been at the meeting

and seen the relics,

had seen the Burnham

telescope pieces there,

wrote to Stebbins

and asked if Stebbins

would consider donating

the Burnham telescope

as a historical artifact for

the new Adler Planetarium.

Now it turned out, Stebbins

at that point had to admit

that he had already promised them to another Chicago museum,

what would become the Museum

of Science and Industry,

which in those days was

called the Rosenwald Museum,

was also under

construction and they had

gotten in there first

and asked Stebbins

about this famous telescope.

Clearly this telescope

was famous in Chicago.

Chicago museums are asking

here about this telescope.

But it seemed both to

Stebbins and to the Rosenwald

that it would be more

appropriate at the Adler.

So they relinquished their

claim to the telescope

and Stebbins agreed to

send the original mounting

and the original tube down

to the Adler Planetarium

to go on exhibit, but

he kept the good stuff.

The real telescope, the lens

and the tube and the tail piece,

the actual functional

telescope he kept here.

And the Adler still has

the original wooden tube,

and the original Clark mounting in their collection on loan.

It's still technically

on loan from us.

We don't have any plans

to ask for it back.

But they have it there,

unfortunately not on exhibit,

but they do have them in storage

there at the planetarium.

Well so at this point,

the pieces have separated

kind of widely now.

The tube and the mounting

have gone off to Chicago

and the original telescope

is here but it's in storage

at Washburn Observatory, and

it stayed there until 1956.

Probably pretty much forgotten,

but not by an enthusiastic

amateur astronomer

from Appleton, Wisconsin,

named Jerome Knujt.

Knujt had read

about the telescope,

knew that it was here,

and by his own account

drove to Madison to see it.

And looked up Albert Whitford,

who was Joel Stebbins' successor as director of the observatory.

Asked about the

telescope and found out

that it was still in

storage in the observatory

and he asked if he

could borrow it.

I don't think we would

lend it these days,

but he must have

impressed Whitford

because Whitford's yeah,

okay, you can take it.

And so it goes on another

trip for a few years.

Comes out of storage and Knujt

had a significant observatory

up there in Appleton.

That's a picture of

him in his observatory

looking in a pretty

big telescope there.

And piggy backed on

that big telescope

is the Burnham telescope,

that's the other one up there.

His plan apparently was to

compare a six-inch refractor

with a six-inch reflector.

So beyond that I don't really

know what he had in mind,

but he had the telescope, he

had the Burnham telescope there

for a couple of years.

Nearly three years at his

observatory in Appleton.

And by the summer of

1959 it had to come back

because in the meantime

the new wing of Sterling Hall

where the astronomy

department is now

was under construction and

the planning of that new wing

included a dome on the roof

intended for the mounting,

the remounting of

this telescope.

And so it came back to

Madison and it's now been

reunited with Romare's mount.

So this is a contemporary

picture here of the telescope.

That's the Romare mount that

was installed in about 1927

originally with the steel tube Burnham refractor up there

and it's been there

now for nearly 60 years

which is longer than it spent

in any other single place

during its

peripatetic existence.

And it will soon

be 150 years old

and it's still in

active use by students

who get a brief

training session on it

and then are able to use

this famous telescope to

learn the ropes of

being an astronomer.

So it's very appropriate that

students could get to use

the oldest and perhaps

most widely traveled

of our telescopes

here in Wisconsin.

And with that I'll thank you

very much for your attention.

And...

if you'd like to read the

published version of this talk,

the citation is up there, so

thanks very much

for coming tonight.

Share this page