The Telescope Optics
This section presents the details and a
discussion of the optics
that are presently in the Galileo IMSS 2428 telescope and the optics
we used in replicating this telescope.
Below is a schematic, not to scale, for
a visual aid to help our understanding of what the eyepiece and objective
physically look like and an optical ray diagram of a Galilean type
telescope The path of the rays of light through the
lens was reproduced from a 1860 text on Natural Philosophy.
Technical uncertainties in the optics of
Photo by Jim & Rhoda Morris taken for The TV special Brilliant Minds
Note that both lenses are double
convex or double concave in this 1860 drawing. We have found this to
true for drawings from at least 1800 up to today. See
Galileo-Telescope-Anomalies-optics This is not at all
what Galileo had a mix in his telescopex. He had both plano concave and
plano convex lenses. Is this important? Absolutely.
This is a good example of a technical error in reporting on
Galileo's choice of the lenses which are the telescope. Further it
is an error in descriptions on one of the
most historically famous, international
telescopes. An error that has stayed with us for hundreds of years
replicating its self over and over again..
Neglected errors of this sort is not
good science or reporting of science. It distort our
view of what Galileo and the early lens makers knew about optics in
the1600's and the issues of who invented what and when. From
the professional literature if true Galileo did not invent the
telescope but did invent one with higher power using lenses
with one of the surfaces of each lens with such little curve in it
that one can say that it was flat. He also used a negative lens as
the eyepiece. The use of double curved lenses and more than
two lenses are other inventions and most likely other inventers.
Galileo's telescopes are
extremely important symbols of what basic research is really about.
Words are Powerful Enough To Express
The Importance Of Basic
so we start off this section of optics with an example of the
importance of accuracy in our choice of lenses. When we look at
Galileo and through his telescope and use him and his telescopes as
symbols of what science is all about here is example of distortions
of science that misleads us about science.
There is no room for sloppiness in science or reporting about
science. The most essential tool of scientific research
is "accuracy" in the treatment and presentation of data, data from which we development conclusions. When the scientific world
present (publishes) their data publicly or in private communications
More important than the data itself is the qualification of the data.
How accurate is it and how was it taken etc.? Using this tool is one of the
reason science has been so successful. Each piece of data lays the
ground work for next collection of data etc.etc..
Our choice of lenses;
One of the many departures often
made in building replicas of Galileo telescope is to
compromise in the focal lengths of the lenses. Galileo's
objective of the #IMSS 2428 telescope has been
reported to be 98 cm.or 95.6 cm. requiring nonstandard lengths therefore costing hundreds of
dollars compared with the much cheaper standard focal length
of one diopter or 100 cm. If one uses the cheaper lens this unfortunately leads to a domino affect of compromise. It
changes the over all length of the telescope by almost an inch which in turn alters the location of the gilt decorations on the body of the telescope and it also changes the optical power. Where
does it stop? If we use the powerful story of the Galileo
telescopes to teach people about how science works. how can our
audience trust us if we don't even use the first basic rule of science,
accurate repeatable testable measurements of time length and mass in building this symbolic
Our finial choice for the lenses and
why. Conflict in the modern measurements of the
exiting lenses at IMSS
The objective: see our references
We have chosen to use the 1992 Greco etal. ref-----980mm.
f.l. measurements rather than the
1923 Ronchi's etal. 956mm focal length for the objective. There are
for this decision.
1st The over all length of the body of the telescope is too long to focus the telescope at
infinity with an eyepiece of 5 cm focal length. The eyepiece
would have to have a considerably shorter focal length resulting in powers greater than 20.(look
further on in our web site at how to determine the over all
2nd If one takes The Refractive index of
Ronchi's calculation and his measured radius of curvature
one calculates the focal length to be 980mm..rather
than 956mm. An inconsistency within the data is suggested.
3 Greco etal. must have known of the difference of his and Ronchi's measurements
because he references Ronchi therefore we feel that it can be safely assume he would have checked and rechecked his data to be sure
his measurements were correct.
This lens is not the original so we have to make an
independent decision. based on measurement and experience.
and our effort to reproduce it as it was originally.
There is a fair agreement that the original eyepiece has
been misplaced. so
We We have chosen to use a plano concave eyepiece instead of the biconcave lens as is presently
the current telescope but use the same focal length based on
our arguments of telescope length and our measurements of it
We use three rational for this decision.
1st The other longer telescope IMSS 2427 uses a plano
2nd there a fair consensus that Galileo made
a number of his own lenses so it was simpler and faster for Galileo to make a plano-concave lens.
For the most part he only had to grind and finish one rather
two surfaces. Grinding is faster than polishing and he
would have only one surface to polish..
3rd There are significantly fewer errors going this
way, Errors like getting the two radii lined up etc.
which In our opinion Galileo would have certainly known
about from his experiments. never the less if our
choice has been wrong
its simple to change the lenses.
Overall length of the telescope is determined by the optics
There is an Inconsistency in the length of the IMSS
#2428 telescope. It is reported that the length of the telescope is
the same as the focal length of the objective. This does not leave
room for the eyepiece when focused on distant objects.
Total length of a telescope focused for infinity
= Focal length objective + Focal length eyepiece + lens holder over
NOTE the overall length will vary
depending how far the lens have been extended for focusing. It
both the object and the eyepiece can be used to extend or
reduce the optical length for focusing. (see figure 9) this maybe
about 10 cm plus 20 cm for both.
The present telescope at IMSS has an objective that is plano convex
with a focal length of 980 mm and a diameter of 37mm. The eyepiece
is a biconcave with a focal length of -47.5mm and a diameter of
The optical length of the telescope for an object at infinity would
be the sum of the focal lengths, namely
(980 -47.5) =
932.5 mm. add 12 mm for the over hang in the holder.
This gives calculated figure for the over all length of the IMSS
telescope closed of 944.5 mm. We have measured the
scope at IMSS, with the apparatus described above, plus a
video showing the operation,, to be 945 + or - 5mm which depends on the
position of the eyepiece and objective tube. It looked to be closed
when we measured it.
Our best guess at presents' that it can open 20
cm more giving a length of 1165mm. for focusing on nearby objects.
The catalog of early telescopes
by Alert Van Helden, page 30 lists the telescope's overall length as
980 mm., which is off by about 35 mm. or nearly 1 3/8 of an inch
different. according to our measurements
The objective has a focal length of 980 mm lens which is not a
standard production item and therefore an expensive
piece to purchase from out side sources. In stead we purchased four 1000mm fl. lenses and shortened them to the to 980mm fl . .
We tested the process with plane glass blanks and found that we
can make changes in the shape at a rate acceptable to changing the
focal length of our 1000 mm. lenses to 980 mm. See photos below
General details of the
equipment assembled to shorten the 1000 mm focal length lens to 980
We have tested the process with plane glass blanks and found that we
can make changes in the shape at a rate acceptable to changing the
focal length of our 1000 mm. lenses to 980 mm. See photos below
Here is a web site
that explains how the lens testing method that we are using works
Optical diagram of lens testing apparatus
Close up of the lens holder and optical flat
We tested the polishing machine using a 2 inch diameter 1/8"
thick plane glass blank. with 4 minutes of polishing we took
off about 46.4 millionths of an inch and converted it to a
convex surface. The photo above shows the interferogram of
our glass blank with the interference lines use to get this
measurement. It's going in the right direction with
reasonable speed. All we have to do is get good spherical
surface and not overshoot the focal length of 980 mm.
close up of the light source and the
Lens polishing /grinding
machine that we've put together for this project.
We are going
to use it in an attempt to polish down the focal length of the
1000mm lenses to 980 mm.
5. The all important art
This telescope was not destined to go to a colleague but
to a customer of high rank and station and is an important part of
the Galileo story, It is a symbol of his marketing and entrepreneurship.
is no strong evidence that Galileo would have done the gold leather
stamping himself his the choice of the artisan was no less critical
to him then the rest of the detail of producing this telescope,
beauty and flattery had to be part of his skill set. So as it is
today. One stopping to visit and admire this telescope
deserves no less than to be treated as one of high rank and
station if we are to gain their support of basic scientific
Developing the art work from photos contains many
complex issues. It has been a slow and exacting process extracting
the shape and detail of each of the deco elements from our high
resolution photos which show each dent, scratch, warp and hand made
irregularity. Rhoda and I have spent hundreds of pleasant hours
deciphering and unfolded the detail to get as close a match to the
orginal hot stamp as possible. the outcome of this work are more
than 20 hot die.
Below is a fairly detailed discussion of
the methods we have used to select build up, and clean up, the photo
images for the art work we have been using to make the black on
white figures to engrave the hot stamps that are used to make the
gold foil impression on the leather of the telescope. Details like
the black and white drawings also have to take into account the
impression process leaves a figure that is somewhat different than
the engraving on the stamp. p.s. (Even the
description of how it is done is long and tedious. But the results
have been satisfying).
To make a faithful replication of the gold art work
on the telescope one needs a lot of high resolution photos of the
telescope showing this detail.( our visits to Florence and Chicago
produced them and, the wonderful here-to unnoticed structural
features of the telescope). Even so it takes some time to get a
feeling for what the original figure looks like because each
component although made with the same stamp experiences a different
history of application and ware and tear.
More General Background Information
About the Art Work Decorations are
applied with a "heated" stamp pressed on a piece of
treated gold foil laid on the surface of the
leather. Up to 20 or so pounds of pressure is
applied to the leather embossing the figure and
gluing a gold film to the inside of the impression .
The stamps we are having made are out of Magnesium
plate by printed circuit board type of technology
using a photo resist coating on the magnesium. We
supply the black on white pattern for the figure to
be etched on the medal to the vender who makes a
photo negative See figures 6A and 6 B. these are
used is to exposed the image on the plate. The
unwanted portions are etched away leaving a stamp
which is cut away from the plate and then mounted on
7A Below are photos of the original telescope at IMSS and a replica
displayed in the Adler planetarium Chicago Ill. Florence,
Italy c 1930. We have modified the photos of the replica
substantially to make the decorations stand out more clearly. This
has altered the colors from their true appearance. One can see
substantial differences between the two scopes in the deco details
as well as the eyepiece which does not show the small sliding focus
6.An example of generating the
data to make a stamp for Gold embossing the Decorations.
First Guess at Shape of Die. Not good enough. By the way this is
reported to be a dolphin.
|Even the beautiful photo
below shows loss of data in the flowers on the
top and one of the feet below. In this case we
have had to take a parts of one image and add it
to another to get the lost detail.
there has been a loss of symmetry in the two
branches because of the way that the craftsman
applied the hot stamp.
So all of the individual deco's are a composite
of several photos
With our discovery of the c 1930
Guilio Cipriani, replica at the Adler planetarium presumably made
from the original number 2 in Italy we found substantial difference
between the original and the Adler. But the Adler was important
because of its finer detail than what is left of the original. Thus
we were fortunate to obtain more detailed photos and provenance.
before we committed to an order for the stamps. This has turned out
to be very important to the project
To reiterate, there are a number of reasons for the differences of
the components of the decorations.
1, damage to the figure, scratches or digs
2, different application pressure
3, different orientation by the artist applying the figure.
4, previous restoration, stretching of the leather, etc.
5, the selection of the particular design component
The above black and white figure so far is a composite of the best
images of the original telescope. The Adler
Guilio Cipriani, replica has given us some added detail for a
One of the tricky things about supplying
the art work
is that the impressions on the leather from
the hot stamp are not exactly the same as the black and
white art work supplied! The gold embossed images
are broader and less sharp than the stamp. The deeper
the stamp impression the broader the outline of the
image. Obviously the impression has walls which are
coated with the gold leaf. The walls are not truly
vertical but slant, the slant making the image broader
to the observer. The slope depends on the physical
characteristics of the leather and the depth of the
impression. The softer the interior and the harder the
surface of the leather the shallower the slope of the
walls and the broader the art work.
|The comparison above of the
variations of a single component in the art work
of Galileo's telescope versus a number of
die's and a 1920's replica by
Cipriani shows how different the outcome can be.
We made several sets of stamps until we were
satisfied by the tests described below.
Extracting data from the figures on the
orginal to obtain a suitable reproduction is a
Below we take you through
several steps in. the process including the
creation of a guide jig for applying the
stamp that would allow the natural operator
randomness of placing the stamp on the leather.
Art work on monitor is
from Cipriani replica The art work on the telescope
has at least 20 distinct components a few can be
combined to perhaps 15 individual stamps. To save money
on the project we have put about 20 figures on a single
sheet of art work thus making a one step operation,
producing one large plate of Magnesium full of dies
which reduces the cost of put out sourcing in this step
to one tenth. The photos shown below is a single piece
test of the operation less the trimming of the die
around the working face .
Again Art work on monitor is from Cipriani
The deco components are of course on a cylindrical surface and the
camera records them on a flat surface distorting in a cylindrical
sense the figure you are trying to replicate. The technique we
developed to unfold this image distortion incorporated both
mathematical and non-mathematical methods. We printed out the
best estimate of the components of decos bands and fixed them
to a solid wood mockup of the scope. Then took photos of our work
and superimposed them, using Adobe Photoshop, on to our photos of
the original. This technique gave us a very clear view of the over
all comparison of the replication. It gave us at a single glance a
highlighted view of the differences especially the ones that
needed correction. It also clearly showed the precision of the
orginal artist making the gold imposed stampings. The authors also
made cylinders of each ring to use in a hot stamping jig discussed
below. Last but not least the mockup can be handled roughly giving
the craftsman a real time three dimensional over view a guide of the
location, sequence, and arrangement that the stamps that have to be
applied to the leather. This method helps us make a truly unique and
The plate of hot stamp dies
- The steps to make the die are
- cut the die from the plate
- hand trim it
- mount it with a stub handle to
attach to a the working handle.
Figure 7A the hot stamp in the rough cut from
a larger plate.
Applying The Gold
next to the final step is hot stamping the gold embossed
decorations. The hot stamping was quite a challenge. There is
a 60 sec video of it happening. The telescope
has a number cylindrical diameters, conical sections including
telescoping sections. For all of its simplicity its a complicated
little beast nothing really square to use as a reference point .
universal hot stamping jig.
After a number of practice sessions by us and professional craftsmen
it was clear that one could not get sufficient precision locating
all of the deco components by hand with out the aid of a series of
positioning jigs to help locate the die . Rather than making individual jigs we decided to design and make a universal jig which
is shown in the photos. Our hot stamping jig is designed to help the
craftsman navigate through the collage of better than a four hundred
impressions. This jig is essentially a self registering "T" square
that indicates to the operator what part of the decoration is being
worked on. The telescope lies in a "V" trough at the base of the
jig. In this photo we have placed a test piece in its place and are
running through a trial stamping to check the procedure. Our
universal hot stamping jig is a series of locating translational,
rotational and centering devices fitted together on to a single
base. It helps free up the operators hands to concentrate on the
stamping process. For example the wheel C in figure 4 in the photo
below carries a sample of figures to be stamped on a given band.
This is used to coordinate the application of the individual
impressions. It is connected to the telescope through a threaded rod
.We have added self centering judicial line for the rotational
orientation. It hangs on the bottom of the vertical metal 18 inch
tall strip that can be seen on the right of figure 1 . Close up
shots of most of these items are shown in the
The telescopes is covered with leather and is in the
jig to go through the gold embossing steps. The operator uses this
self orienting "T" square to locate the hot s stamp.
As out lined above there a sizeable number of
discreet patterns most of them interlock with their neighbors.
Its important to note that the
principal role of this universal jig is to locate a starting
point for one corner of each die. It is important not to acquire a machine made like appearance to the
embossing. It is vital to retain all the uncertain hand
variables that a skilled craftsman has and that is so
clearly visible on the orginal telescope. So except for the first
contact point the rest the impression has been left up to the
operator which includes rotation, and variable hand pressure.
The cylinder is a layout guide attached to the telescope thru a
threaded rod and rotates in synchronization with
the scope. It carries a full scale picture of the details of each
decoration band. The fiducial line aids the operator in applying the
hot stamp die to the leather in the appropriate location.
Finally a skilled craftsman applying the hot stamped decorations with the
aid of our self orienting "T" square. The telescope is nearing
completion. The final step is a slight darkening step to the leather
to reach the correct color scheme of the original when it was new as
described by Van Helden .
start video of the finished telescope click twice below on arrow lower
left corner of screen.---------------------
Copied from WokipediA The Free
With the loss of many of
his defenders in Rome because of
Dialogue Concerning the Two Chief World
Systems, Galileo was ordered to
stand trial on suspicion of heresy in
1633. The sentence of the Inquisition
was in three essential parts:
- Galileo was
recant his heliocentric ideas,
which were condemned as "formally
- He was ordered
imprisoned; the sentence was later
commuted to house arrest.
- His offending
Dialogue was banned; and in an
action not announced at the trial,
publication of any of his works was
forbidden, including any he might
write in the future.
After a period with
Ascanio Piccolomini (the Archbishop
Siena), Galileo was allowed to
return to his villa at
Arcetri near Florence, where he
spent the remainder of his life under
house arrest. It was while Galileo was
under house arrest when he dedicated his
time to one of his finest works,
Two New Sciences. This book has
received high praise from both
Sir Isaac Newton and
Albert Einstein. As a result of this
work, Galileo is often called, the
"father of modern physics"
It sure took some time to come
around to Galileo's discoveries
Galileo was reburied
on sacred ground at Santa Croce in
1737. He was formally rehabilitated
Pope Benedict XIV authorized the
publication of Galileo's complete
scientific works (a censored edition had
been published in
1718), and in
1758 the general prohibition against
heliocentrism was removed from the
Index Librorum Prohibitorum. On
Pope John Paul II expressed regret
for how the Galileo affair was handled,
as the result of a study conducted by
the Pontifical Council for Culture.
THESE LITTLE GUYS NEED YOUR HELP FOR THEIR FUTURE. SUPPORT BASIC RESEARCH IN THE SCIENCES.
BY CALLING AND WRITING YOUR CONGRESSPERSON TODAY.
Telescopes and Pieces of Telescopes. We are told ref 1a, 2a that
Galileo built a number, maybe as many as 60 telescopes and lens
sets, in the process of doing and reporting his famous research
work, Some believe that only the objective lens of "the data scopes"
is left and that's broken into several pieces.
Not all of the telescopes he built or had built
were used for research data purposes. But there are two telescopes
left from this era which are very important to us today, especially
a beautiful leather covered scope and a companion for comparison
demonstrates what a basic research scientist has to go through to
get funding for his work. A very serious problem that still exist
today. There are two telescopes that are assigned to Galileo that have
survived, one a roughly built paper covered working telescope, and
the other a leather covered presentation telescope, both are n display
at the IMSS in Florence Italy. The original leather telescope that
we are replicating has become as important, in later years, as the
pure research telescopes. There are at least two compelling reasons
that come to mind for this.
The first reason is because
this telescope, exists because it was beautifully built. It used an
ingenious wood stave design that allowed the various diameters of
the scope to be easily fabricated from the same flexible
construction material It was beautifully covered with leather of
different colors and embossed with myriad patterns of elegant gold
tooling. Since it was a piece of art it undoubtedly was treated with
greater consideration which accounts for its long lifetime. So in a
sense when you visits the little leather telescope or its replica be
assured that Galileo intended it as a work of beautiful art for your
deserving eyes and that he is personally offering it to you for your
The second reason for its importance is that this
piece of art served as a presentation instrument for Galileo when
he was announcing his extraordinary findings to those of wealth and
power that controlled the financing of his scientific work. He used
it as a communicating tool, a grand gift to his sponsor. It
still servers in this role today.
It is a living demonstration
that scientists even with their current track record still
have to communicate across many borders, perhaps even gild the Lilly
as Galileo did, to obtain support for their basic research work.
Scientists still have to struggle for endorsements of their studies
from the government and public on technically
matters of great concern, such as environmental research, stem cell
research, etc. It reminds us that science and religion can still be
confrontational and that the military is still one of the strongest
supporters of science.
But its greatest value is
that it has drawn people together to marvel at the sites to be seen
in the sky through two little pieces of glass. There is a macro
world out there that is still to be discovered and understood. So
this famous little leather telescope, and hopefully also
its replica, is still being pressed into the same service today as
it was originally by Galileo in 1600. It helps people gain more
enjoyment and a better understanding of the universe we share with
Here is a url for a few more details of the trip:
photos of the telescope, more of the IMSS staff,
and the country side.
is it important to make a museum grade replica in
its most complete form inside and out? Why spend hundreds of hours of research and building such a replica?
1st, One can appreciate the telescope more because it is not an almost replica, only skin deep, made
out of plastic or cardboard, with an almost correct optics
and dimensions. It serves as a more honest display for the
public to visit and study.
2nd, Its a tactile time capsule. It is a more complete record than a digital or paper one It is what the original telescope is today. with all of its
modification over the past 400 years. Further, if for some
catastrophic reason the original is lost there is at least a precise
replica to help keep the record straight as to what it was like in
3rd, Its has a greater research and
teaching value. The rather unique method in construction of this
telescope helps one to judge and understand the mechanical aptitudes
of Galileo and his associates.
4th, It helps one get a clearer picture of the early
experimenting in the kinds of materials, tools, and techniques
that had been tried for constructing telescopes
as a commercial opportunity. It demonstrates another first for Galileo. A type of telescope tube construction that was
the forerunner of some of the large polygon wood telescopes. and the
use of resin composite
construction to make telescope tubes and lens holders more rugged
and resistant to the vagaries of moisture and rough handling.
5 fifth, Then there is the poetry part of
life. If one should be the lucky enough to handle and use a
faithfully produced replica one would get the full experience that
Galileo had when he was using the telescope, the same visual and
tactual sensations that Galileo had four hundred years ago. You
would find all the good and not so good design and construction
issues, the cranky limited field of view, the color and other
optical aberration in the image, its firm light weight
constructions. Your experience would be an accurate replication of
Galileo's experience giving one a more emotional appreciation for
Galileo's skill and intuitive nature.
There is a second question in replication often
brought up for debate.
6th, From a practical point
of view it has higher monetary value if the instrument has been
After spending all the effort
required to produce a museum quality clone inside and out (optics,
supporting structure and decorations) does it make sense to destroy
all this careful work with sand paper, steel wool, dyes, acids, and
alkali solutions in the name of "antiquing" it?
There are many ways of looking at this question. I've chosen four.
How would Galileo feel about this? Just put
yourself in Galileo's place . You come back to your laboratory after
having a tasty lunch and you find that one of your technicians has
taken your most beautiful brand new presentation telescope and
worked it over to make it look like it's 400 years old. Would you be
upset or happy because it no longer shows the quality of materials
and craftsmanship you expended?
Would you want to show
this brand new beautiful instrument as a representation
of your work or antique it with sand paper, steel wool,
dyes, acids, and alkali solutions? At any rate it
would not be as disappointing as being put into jail for the rest of your life for interpreting the data from the telescope in a non-Church supported theory.
2, What would you feel about
Galileo's treatment of you? If Galileo were
alive today and came to give you, or show you one of his
telescopes for the purpose of telling you his story or
to convince you to support your local scientist, would
you take him more or less seriously if he presented you
a with sand papered, steel-woolen, dyed, acid and alkali
treated scope or a brand new carefully crafted
3,Wouldn't visitors lose a truer
connection between themselves and Galileo? Is it not
better and more impressive to you or your visitors that
when the telescope is presented for your inspection, that you really experience the feeling of what it
must have been like to be there when the telescope was
first introduced: shiny, new, and grandest
in its glory rather than being presented with one that
contained all the wear and tear of a four hundred year
4, What about giving respect and
honor to those who have given us something of value in
the past? Isn't the best way of honoring one of the
finest, most famous, though poorly treated early
experimental scientists by displaying a beautiful
replication of his instrument when it was splendidly new
and young just like Galileo, at the top of his world?
inside an outside. This gives the proud
owner a one upsmanship in something very famous and extraordinarily rare.
The American Heritage Dictionary
1a. Catalogue of Early Telescopes by
Albert Van Helden 1999 Istituto e Museo di Storia
Scienza dell Scienza, Firenzze
2a. Sidereus or The Sidereal
Messenger Galileo Galilei Translated
with introduction, conclusion, and notes by Albert
Van Helden The university of Chicago
Press Chicago and London1989
We thank Paul Valleli
of Amateur Telescope Makers of Boston for discussions on
adjustments of the focal length of the objective,
recommending several source of information and generally
paving a path to many resources including contacting
Peter Abrahams of the Antique Telescope Society who very
kindly supplied the references below. Also the is a
well rounded collection of references and
relevant information pictures plus interesting critiques
maintained by Jim Mosher. Tom Pope both experience
1, Baxandall, David.
Replicas of Two Galileo Telescopes.
Optical Society 25:3, (January 1924)
Pettit, Edison. A Telescope of Galileo. Publications
Society of the Pacific
51 (June 1939) 147-150. (#301) (replica
3(Galileo) Barr, E. Scott. Men &
Milestones in Optics, III: Galileo
Applied Optics 3:12 (1964) 1321-1328.
4(Galileo) Drake, Stillman. Galileo Gleanings VI:
Venice. Isis 50:3 (Sept. 1959) 245-254.
5(Galileo) Drake, Stillman. Galileo's First
Telescopes at Padua
and Venice. Isis
6(Galileo) Greco, Vincenzo, G.
Molesini, & F. Quercioli. Optical
Galileo's lenses. Nature 358 (July 9, 1992) 101. <&
6a V. Ronchi "Sopra i cannocchiali di Galileo," L
7(Galileo) Greco, Vincenzo et. al.
Telescopes of Galileo. Applied
Optics 32 #31
(Nov. 1993) 6219.
8(Galileo) Miniati, Mara.
Examination of an Antique Telescope.
9 (Galileo) Ringwood,
Stephen. A Galilean telescope. Quarterly
Royal Astronomical Society 35 (1994)
10 (Galileo) Sonnefeld, August.
Optical data of Galileo Galilei's
telescope. Jena Review #6 (1962) 207-212. <.jpg>
11 (Galileo)Westfall, Richard. Science and
Patronage: Galileo and
76 (1985) 11-30. <& .pdf,.tif>
(Galileo) Zik, Yaakov. Galileo and the Telescope.
13 (Galileo) Dupré, Sven. Galileo, the Telescope,
and the Science
of Optics in the
Century: A Case Study of Instrumental Practice in
Universiteit Gent, Belgium, 2002. 366pp.
14 (Galileo) Miniati, Mara, et al. Examination of a
telescope with the
Galileo. Optik 101:3 (Jan. 1996) 140-142.
(Galileo) Greco, Vincenzo et. al. Modern Optical
Testing on the
Paolo Mazzoldi, ed.; From Galileo's
16 Optoelectronics, conference Padova June
World Scientific, 1993.
ref replica Hale had made
Title: A Telescope of Galileo
Journal: Publications of the Astronomical
Society of the Pacific, Vol. 51, No. 301, p.147
Bibliographic Code: 1939PASP ..51 .147P
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