Idle Diffractions

Wachendorf?

So, I am doing a little research on the history of aspherics.  I learned one thing.  The earliest written reference I found so far is a US patent by Abbe, US 697,959, filed in 1899.  Along the way, I came on the name of Fritz Wachendorf.  A new name for me, and interesting unto itself, but, even more interesting for the following, unrelated Google search experience.

Let’s say you are interested in finding out the most significant books specifically oriented to optical design.  Here is what to do:

1. Go to www.scholar.google
2. Type “F. Wachendorf” with the quotation marks

At least at the moment, where I am, the second item should look like:

[CITATION] Bestimmung der Bildfehler 5. Ordnung in zentrierten optischen …
F Wachendorf - Optik, 1949
Cited by 7 - Related articles

Now, click on Related articles and you should see, near the top,

[CITATION] Geometrical Optics
JG Baker - Fundamental formulas of physics, 1955 - Prentice-Hall
Related articles - All 2 versions

Now, click on Related articles again, and you now have pretty much the top 100 books in geometrical optics. 

I recognize the list, because I spent over 10 years, in the pre-Internet period, collecting old books in optics and this list parallels what was my collection.  That collection has since been donated to the College of Optical Sciences at the University of Arizona.  However, in a few months, the optics books in that collection that are dated before 1923 will be posted to the ORA website as they were recently scanned by Kirtas books using funding from ORA.  This will begin an exciting opportunity to get your own e-book, soft-cover, or, even hardcover version of the classics in optics, including, for example Coddington, from 1828 and Airy from 1850. There will be more on this, soon.  Try out the search series – the book list is really great.  And, there are a few articles that are interesting if you have missed them.  The one below for example. 

[CITATION] WHO? DISCOVERED CODDINGTON'S Equations?
R Kingslake - Optics and Photonics News, 1994 - opticsinfobase.org
In these formulae, s and t represent the distances from the point of incidence of the traced ray
to the sagittal and tangential object or image, measured along the traced principal ray, and r
is the radius of curvature of the refracting surface.

And, there appears to be a new book on photographic lenses out (don’t buy them all, I’m ordering mine tomorrow).  Looks good, especially if you happen to read German.

 

Connections: before optical glass there was …a furnace?

A few years ago, I came to the somewhat soft conclusion that the world of optical design can be defined to have really started in 1886, when Schott, Abbe, and Zeiss got together and, with the help of new glass formulations, started to design optics, particularly for microscopes.  But then at last fall’s UK Optical Design Meeting, Jon Maxwell, formerly of Imperial College, handed me a paper on one William Vernon Harcourt (1789-1871) and said I “might find it interesting.”  He was right – and it changed my opinion of the origins of optical design.

James Burke’s documentaries, called Connections, have always been very impressive to me, because Burke did a wonderful job explaining how seemingly unconnected scientific discoveries and other historical events build on one another to bring about technological advances. Connections is available on DVD, and some episodes are also on YouTube.

I mention Connections because Harcourt made optical glass 50 years before Schott, but he did it not because he had a passion for glass, but because he had a passion for furnaces.  Harcourt had made essentially the world’s hottest furnace, and there was then a question of what to do with it. At this point, Michael Faraday (1791-1867) apparently broached the idea of using the furnace to make optical glass. Later, G.G. Stokes (1819-1903) moved the ball forward by encouraging Harcourt to try more experiments with optical glasses (at this point Faraday had shifted his focus to electricity). In the 1830s, as science was emerging really for the first time, there was a small group in England that formed under the affiliation of the British Association for the Advancement of Science, of which Harcourt was a founding member.  If you’re interested in finding out more about these connections, there’s a nice article by E. Scott Barr in the first volume of Applied Optics, where one finds a story on Stokes.

 
Example of furnace for the manufacture of optical glass, by Henry Bessemer, circa 1850. Bessemer presented a paper on mass production of steel to the British Association for the Advancement of Science in 1856. Image from Sir Henry Bessemer, F.R.S., An Autobiography, 1905.

For more information:
E. Scott Barr, “Men and Milestones in Optics,” Applied Optics, Vol. 1, No. 1, 69-73 (1962).

M. Cable and J.W. Smedley, “William Vernon Harcourt: pioneer glass scientist and founder of the British Association,” Glass Technology, Vol. 33, 92-97 (1992).

One of the Most Significant Collections of Scientists in History?

I am fortunate to know, and live a few miles from, Prof. Emil Wolf, known for many things, but perhaps most popular as the author of Principles of Optics, with Max Born, 1959 (they have a first edition at the U of R., my version, bought when I entered optics, in Arizona, in 1976, is the 5th edition). He was recently honored for giving one paper in each of the last 50 years – how amazing is that?  We (my wife Prof. Jannick Rolland and I) try to go over, with the kids (Yvan 16, and Roman 14), at least once a month, to collect some of his stories.  The other night, he brought out, as he often does, something from his “collection”.  This night, he offered that we could take it home and try to create a copy (without opening the frame – as you will see this reveals some interesting features of slim digital cameras).  Shown below is a photo given to him by Max Born from a conference in 1927. 

Beyond being a fascinating collection of scientists, it illustrates nicely that these slim digital cameras have some serious barrel distortion. 

Although you could expand the photo, I’ll make it easier.  Most prominent is Albert, in the front row, just right of center, unmistakable.  What about the others?  I knew many, in fact most of them.  I had a few minutes (it’s Saturday morning and I’m sitting by the fire), so I thought I’d Google (Scholar) those that I knew little about.  This, of course, became immediately much too interesting.  The first one, in the lower left corner is “I. Langmeir”, for whom I knew nothing, other than recognizing the name.  Google Scholar does not reveal him on the first page.  Straight Google points to Wikipedia, who spelled his name as “Langmuir” and labels him as an atomist.

Irving Langmuir
Following World War I, Langmuir contributed to atomic theory and the understanding of atomic structure by defining the modern concept of valence shells and ...
Biography - Patents - See also - References
en.wikipedia.org/wiki/Irving_Langmuir - Cached - Similar

Even more fun, is the next link is to CERN, and, amazingly, this photo (with better quality).  Links to follow imply he traveled often with Madame Curie, who appears two seats to the right of him.

http://doc.cern.ch//archive/electronic/cern/others/PHO/pauli-archive-pho//016.jpg

Next, to the right we find, Max Planck, known best for Planck’s constant,

Max Planck
Max Planck (April 23, 1858 – October 4, 1947) was a German physicist. He is considered to be the founder of the quantum theory, and thus one of the most ...
Biography - Religious view - Honors and awards - Publications
en.wikipedia.org/wiki/Max_Planck - Cached - Similar

There was also the following link on the lead page, that was interesting and relates to describing his Nobel prize. 

He is followed by Madame Curie, best known for contributions to understanding radioactivity.
n.wikipedia.org/wiki/Max_Planck%23Honours_and_awards&ei=3NxRS-SlEIiWtgeP_qytDA&sa=X&oi=oneline_sitelinks&resnum=1&ct=result&cd=3&ved=0CAsQ0gIoAg&usg=AFQjCNFK6GLcRm3AvCw7tyA9uqUXYrRJNQ
Marie Curie
Madame Curie was decorated with the French Legion of Honor. In Poland, she had received honorary doctorates from the Lwów Polytechnic (1912), ...
Early life - Sorbonne - New elements - Nobel Prizes
en.wikipedia.org/wiki/Marie_Curie - Cached - Similar

It is interesting to note the rest of the Google page lists biographies written on her, including one by her daughter – has anyone read this one?

Next comes H.A. Lorentz, who I recall as related to my E&M classes and some plots with someone else I cannot recall.  Again, we can resort to Wikipedia, to find:

Hendrik Lorentz
Hendrik Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the ...
Biography - Legacy - See also - References
en.wikipedia.org/wiki/Hendrik_Lorentz - Cached - Similar

The rest of the Google page is overtaken by links to one John H. Lorentz.

Lowry Hill - Biographies - John H. Lorentz
John H. Lorentz. Director of Alternative Investments. At age nine, John Lorentz completely dismantled his bicycle (much to his mother's horror) only to ...
www.lowryhill.com/biographies/ops_j_lorentz/ - Cached - Similar

I’m not going there, although I am curious to see what comes after “… only to …”

You can solve this inconvenience by noting the photo says “H. A. Lorentz” and going with that you get an interesting cover page in Google.  He received the Nobel Prize in 1902 and was selected for Project Gutenberg.  His books, some written about Einstein’s theories and some written with Einstein (and Minkowski) are available even now from Amazon. 

Next comes our hero, Albert…

Albert Einstein
Albert Einstein was born in Ulm, in the Kingdom of Württemberg in the German Empire on 14 March 1879. His father was Hermann Einstein, a salesman and ...
Early life and education - Marriages and children - Patent office
en.wikipedia.org/wiki/Albert_Einstein - Cached

also on the Google cover page we find this fun image,

I may have to do something with this.

To his right, P. Langevin, again, a name to me, where we find,

Paul Langevin
Paul Langevin (23 January 1872 – 19 December 1946) was a prominent French physicist who developed Langevin dynamics and the Langevin equation. ...
Life - See also - References - Sources
en.wikipedia.org/wiki/Paul_Langevin - Cached - Similar

 

One useful quote from the Google cover page is “Paul Langevin was the first person to write the 'Newton's equation' for a Brownian particle. ...”

Also on the cover page, we find he was Madame Curie’s “companion”, which at one point he defended by offering to duel, with real pistols – someone let me know what happened next?

Continuing right, we have next E. Guye, I had not idea who we have here, Google says, basically, he was at the 1927 conference – he does not rank a listing Wikipedia, yet.  As a result, his Google cover page lists a number of different links to the 1927 conference, and an earlier one in 1911.  His name is linked with DeBroglie and Lorentz-Einstein experiments.

Towards the bottom of the page is a great blog link – “the Lousy Linguist"
http://thelousylinguist.blogspot.com/2008/06/when-conferences-meant-something.html

Here you find the quote:

One of my all time favorite pictures, this comes from what may have been the most valuable academic conference in history, the Fifth Solvay International Conference on Electrons and Photons held in Brussels, Belgium 1927. Rarely has a single conference involved such critical debate about a new theory (I'm no physicist, of course).

From Wikipedia's page: "Perhaps the most famous conference was the October 1927 Fifth Solvay International Conference on Electrons and Photons, where the world's most notable physicists met to discuss the newly formulated quantum theory.

How fun is that?  The title of the article is “When Conferences Meant Something”, how appropriate.

OK, two to go (in this row),  next we find another unknown to me, C.T.R. Wilson,

Charles Thomson Rees Wilson
C. T. R. Wilson. The 1927 Solvay conference. Born, Charles Thomson Rees Wilson 14 February 1869(1869-02-14) Midlothian, Scotland ...
en.wikipedia.org/wiki/Charles_Thomson_Rees_Wilson - Cached - Similar

Reading down the Google cover page for “C. T. R. Wilson” I realize I do know Wilson, he discovered, or invented, the cloud Chamber.  There are a number of great looking links on the page, should you be so inclined.

Finally, for today, we have another unknown to me, D.W. Richardson,

Owen Willans Richardson
Sir Owen Willans Richardson, FRS (26 April 1879 - 15 February 1959) was a British physicist who won the Nobel Prize in Physics in 1928 for his work on ...
Biography - Honours - References - Bibliography
en.wikipedia.org/wiki/Owen_Willans_Richardson - Cached - Similar

Yet another Nobel Prize winner.  This is the only case I was forced to click through to fill in the … above.  It reads “…for his work on thermionic emission, which lead (sic) to Richardson’s Law.” 

"If then the negative radiation is due to the corpuscles coming out of the metal, the saturation current s should obey the law  ."[3]

This also made available the photo below, again from this clearly monumental conference.

 

Niels Bohr and Richardson (right) at the 1927 Solvay conference

Born	26 April 1879 Dewsbury, Yorkshire, England
Died	15 February 1959 (aged 79) Alton, Hampshire, England
Nationality	United Kingdom
Fields	Physics
Institutions	University of Cambridge Princeton University King's College London
Alma mater	University of Cambridge
Doctoral advisor	J. J. Thomson
Doctoral students	Arthur Compton Clinton Davisson
Known for	Richardson's Law
Notable awards	Nobel Prize in Physics (1928) Hughes Medal (1920)

Sir Owen Willans Richardson, FRS (26 April 1879 - 15 February 1959) was a British physicist who won the Nobel Prize in Physics.

Since I seem to have exceeded the blog guidelines, 2 pages and 1 figure, and the fire has died down, I’ll save the remaining two rows, and those missing from the photo, listed at the bottom for blogs to follow.  Feel free to respond with more tidbits.

400 Years Ago on January 7, 1610

It seems that the night of January 7, 1610, is recorded in the journal of Galileo as the night that he first saw the moons of Jupiter.  Jane Houston Jones, who writes an aperiodic newsletter for a group of amateur astronomers in Monrovia, CA, has gone to the trouble of commemorating the occasion by posting a scanned image of Galileo’s journal page to a blog site she maintains at JPL.  The link is

http://blogs.jpl.nasa.gov/?p=61

Perhaps even more importantly, she went to the trouble of typing to the side what he wrote (as his handwriting leaves a bit to be desired).  It is worth the click.

Coming soon is a running series of reviews of important antiquarian books in optics and optical design, and some physics and astronomy.  Keep a watch.

WFPC2 and COSTAR on Display

COSTAR
Corrective Optics Space Telescope Axial Replacement (COSTAR), "Contact Lenses for the Telescope," on display at the new "Moving Beyond Earth" gallery in the National Air and Space Museum's Mall building.

Image Number: WEB11281-2009
Credit: Photo by Eric Long/NASM
Copyright: Smithsonian Institution

 

 

 

In a May service mission, the systems WFPC2 and COSTAR were brought back to Earth.  WFPC2 is the oversized digital camera that recorded so many of the Hubble Space Telescope’s iconic images after its installation by shuttle astronauts in 1993. COSTAR is the other optical system that was installed in HST on that same first service mission. Its carefully designed and fabricated mirrors “popped out” into precise locations in the optical path to compensate for the famous error in Hubble’s primary mirror, allowing the originally installed science instruments to “see” sharp imagery from the telescope (WFPC2’s design incorporated its own correction and didn’t use COSTAR).

Now the camera that photographed so many stars is something of a “star” itself, on display in the main space gallery at the National Air & Space Museum in Washington, DC. And COSTAR is there too (pictured above), part of a new exhibit called “Moving Beyond Earth.” 

For more information, see this blog post at National Geographic, this recent article at The Space Review web site, or the press release for the new exhibit.

The 1st Astronomical Observatories in America

Which became an exercise in diversion, including:
the Mason-Dixon line, time-balls, chronometers, Goodyear, giants, and Indians

 

I have recently developed a theory that many, most, and perhaps nearly all of the larger aperture reflective professional astronomical telescopes in the world, built before say, 1970, may suffer from the fact that they were often polished in a horizontal position and tested in a vertical position resulting in astigmatism of varying magnitudes being polished into the mirror.  This then brings in to play my favorite topic, nodal aberration theory.  The figure below is one such example and historically is the first known physical evidence of binodal astigmatism.  For more on this topic, see the short newsletter article that I wrote at SPIE's request following my talk at SPIE annual meeting.

 

Figure 1. Through focus photographic plate taken with the 90” telescope of the Steward observatory, located on Kitt Peak in the mid-1970s. The boxes to the left and right are highly magnified regions of the star plate showing the ellipticity of some of the star images.  The two foci of the overlaid hyperbola are the locations of two positions in the star field with no astigmatism – labeled by Prof. Roland Shack, the discoverer, as binodal astigmatism, which led to a complete nodal theory of optical aberrations, my Ph.D.

 

But, that is not where this blog entry will go.  What was brought to mind was to answer the question, how many large primary mirror based telescopes were built before 1970?  This brings us to “Early American Observatories” by Willis L. Milham, which, happened to be on a recent book list that passed my way.  The “book” was in fact a collection of articles that were bound together for the author, who was “The Field Memorial Professor of Astronomy” at/by Williams College (and perhaps now you are in a position to guess where the first observatory is claimed to have been installed).  This book became the basis for two much shorter articles of the same title published in Popular Astronomy in 1937, (Vol. 45 (if my Roman numerals are right)). 

 

This path of investigation illustrated, yet again, just how fascinating it is to have the Internet.  The articles by Milham are a bit of a ramble, with more than a lot of trivia of who was a professor where and for how long. It seems that although Europe was actively developing observatories, with the likes of Herschel, America was not.  In fact, Airy, of Airy disk fame, is quoted as saying that in 1832 America had not a single observatory.  Not quite true it appears, but close.  Now, here is where Milham fills in for us.  He researched to find there were 11 legitimate candidates to be named early observatories in the U.S. erected by 1840.  Where “legitimate” is an attempt to rule out a 3” telescope in a wood shed, which at this point in time is in fact nearly a legitimate observatory, compared to the alternatives.  The article is readily found from the Google Scholar web site ( www.scholar.google.com) using a search like: Milham, “Early American Observatories”.

  

The outcome being that the Observatory at Williams College is not only the first, but, it is still standing (okay, it was still standing in 1937 when the article was written).  Milham has a quote from then President John Quincy Adams, in 1825, on the topic of forming universities in America (apparently there weren’t many of those either) that “Connected with the establishment of a university, or separate from it, might be undertaken the erection of an astronomical observatory, with the provision for the support of an astronomer, to be in constant attendance of observation upon the phenomena of the heavens …”  However, as it turns out, Congress never really bought into this idea, at least for the purpose of science.  The U.S. Naval Observatory was the first government-sponsored “observatory”, but I believe (and more research is needed) that it was created to help with surveying.  In fact, it appears that anyone in America who wanted the title “astronomer” on their business card in the 1800s would also most likely have the title of surveyor and often minister.  It is impressive then, to me, that the Lick Observatory (a subject of some later blog) was up and running in 1890.  If you ever find yourself in a used book store with any scholarly content, keep an eye out for the publications of the Lick Observatory, typically with publish dates in the 1890s.  These are great coffee table additions (or, if you decide not to, let me know where you saw/left it).

 

Along the way, Milham brings out a topic that has gotten more coverage recently, the importance of clocks, or, in that period, chronometers.  In and around 1840, it was still difficult to determine longitude as this can only be done well with a highly accurate clock, which did not yet exist.  This little detail causes Milham, and now me, to detour and, in his case, tell a long story of the details of placing the Mason-Dixon Line.  I assumed Mason and Dixon were politicians.  But, no, they are astronomer/surveyors!  Who knew?  If you like to clutter your brain with trivia, this is an interesting subject to pick out of the Milham article.  As it turns out then, the funding of astronomy was made in the interest of surveying and a better determination of the all important property line.  I find even now, I typically need a surveyor to keep my neighbors at bay. 

 

The article by Milham, for me, has more diversions than information on the primary mission.  In fact, it told me nothing of large reflecting telescopes, since, there are not any in America, yet.  Another example of a diversion that Milham creates, again related to time, is the topic of “time balls”, I assume like the one that remains in New York for use at New Year’s.  Again, the Internet can provide a whole series of articles on “time-balls” of the period, which were used to synchronize clocks over a large area for the purpose of accurate surveys, if I have it right.  As if this is not bad enough as a distraction, the first time balls were to be made by Goodyear (yes, that Goodyear), who had just figured out how to vulcanize rubber from the Amazon.  I am someone who has a substantial collection of books written by travelers to the Amazon, particularly in the 1800s, and as a result, I have read much on the discovery of rubber.  So, here it comes back in the form of time balls.  This all feels like an episode of James Burke series "Connections", by far the best use of a TV I ever found.

 

The final diversion for today’s blog is giants.  Now, this diversion is not directly Milham’s fault, but he contributes.  It seems there was a Dr. Humberd, who upon crossing paths with Milham, got enough of his attention to warrant receiving his own personally inscribed copy of Milham’s book.  This, of course, is the copy I have come to own.  Based on a prior experience, I now always look in the front cover of a book like this to see if there are any random names from inscriptions or book plates.  I search those names on the Internet, which turn into a full 1-hour talk on optics (I may blog sometime the first time I did this).  Humberd was a medical doctor who, yes, specialized in giants.  His claim to fame was to have reported the tallest (and apparently then dead) person in the world at 8’3”.  The person was most probably only 7’3”.  He also went to the trouble to paste in a cutout from a 1938 editorial advocating U.S. postage stamps of medical doctors.  Here, one is presented with yet another name to trace: Manasseh Cutler, “A versatile man, Cutler collected painstaking astronomical and meteorological investigations … he died in Hamilton, Mass., July 28, 1823.”  Finally, in a rare instance, this book also has a handwritten letter from Milham to Humberd.  The letter basically says to Humberd that the “observatory” he had inquired about was probably not for astronomical purposes but instead was erected to keep a watch for Indians! 

 

I am out of time ... back to the present.  Perhaps I’ll run down Cutler to see where he takes us, in the future.  To close, I encourage you to check out the Milham link.  There is a write-up of Ralph Waldo Emerson’s visit to the Hopkin’s Observatory on the campus of Williams College and, in fact, a wealth of just plain interesting material on the 1800s.  Although my “catalog” says I have it, I have not been able to locate an article by Elias Loomis in Harper’s New Monthly magazine in 1856 titled, “Astronomical Observatories in the United States” in my collection or on the Internet.  This was referenced by Milham and many others along the way.

 

The next blog entry will at least be initiated from the “Catalogue of the 16th Annual Exhibition of the Physical Society of London and the Optical Society, January 5, 6 and 7, 1926”, assuming I do not get distracted by something else first.

Figure 2: The Hopkins Observatory (in 1938), at Williams College, constructed from 1836-1838.

 
 

New Evidence on the Dates of the Oldest Telescopes

Over the weekend I received several books on the history of telescopes from a number of sources, including my ”favourite” source -- the Royal Society.  The books included Charles King’s excellent “History of the Telescope” from 1955 ($75).  If anyone is interested in a copy, there was a second copy available, although it may well be gone by now.   This small collection will form the basis for my current project, creating a list of the observatories of the world -- with two goals.  First, to find how many have primary mirrors that are over about 30" in diameter and are constructed before 1970-1980 (and therefore are likely to suffer from binodal astigmatism).  The second goal is to determine if the database contains enough information to create an optical model of at least the main telescope.  Three of the books have lists of observatories that seem significant.  The list will be posted here when I get to it (holding your breath is not recommended).

On a slightly more informative topic at the moment; this morning's e-mail brought a message from ORA employee Mark Kahan, who mentioned he was having trouble sleeping and found his way to a website on the history of astrophysics.  There he found a recently posted discussion of a painting from 1607 by Jan Brueghel that appears to show a Keplerian telescope some 5 years before it is reported in the literature by Kepler.  This is going to make going to the museum so much more interesting.  It didn’t occur to me to look for optics in the paintings.  The link, which is a quick read and shows the painting could be found at http://arxiv.org/abs/0908.2696v1 and I highly recommend reading it.

The Speed of Light: An Evolving History of Computers and Optical Design

Optical design has always been one of the technologies that have ridden the leading edge of computer technology.  In 1951, James G. Baker, well known later in his career as, among other things, the optical designer of Polaroid’s innovative SX-70 camera, took on the role of principal investigator on what was to become a four-year program to attempt to implement optical lens optimization on the emerging set of first generation mainframe computers that came to include the Mark I, Mark II, and Mark IV generations of the Harvard Card Programmed Calculator computers that were developed by Aikens (Ref. 1).  Dr. Baker summarized his goal as follows:

“…we have before us the problem of transforming the art of optical design as pursued heretofore by the author into a science of optical design, as performed automatically by calculating machines.”  – James G. Baker, 1951

In the initial benchmark, the ray trace speed for the first aspheric surface was 36 minutes per ray surface (0.0005 ray surfaces per second).  In 1998, that number was 1,000,000 ray surfaces per second. Even over the four years when Baker was writing, the ray trace speed increased one order of magnitude as the Mark I evolved to become the Mark IV. 

According to the reports, the work was initiated in August of 1950 in Cambridge MA, at Harvard using the Harvard “Mark I Sequence Controlled Calculator.” Baker reports that as of December 24 (Christmas Eve), the group was using a “reasonably complete IBM set of machines,” including, as he notes, the supremely important Card Programmed Calculator (italics per the original report).  Baker characterizes this device as a “modern tractor with ancient plowshares.”  The actual computer is shown below.  This computer physically resides in the Smithsonian.

This characterization is accurate in that the Harvard Mark I-IV series of computers were not in fact electronic digital computers at all; rather, they were electro-mechanical machines along the lines of Babbage’s 1833 devices, created by Howard Aiken at Harvard beginning in 1937 with funding from IBM, and in fact were driven by a 50-foot-long drive shaft.  Aiken had come across the original hardware developed by Babbage in 1833 when he tried to develop (with only limited success) the first mechanical computer; the hardware was essentially lost in the archives at Harvard.  In studying the machine, Aiken came upon the concept of “a switchboard on which are mounted various pieces of calculating machine apparatus.” This became the Mark I.  It is worth noting that the Mark I was only 10X faster than the 1833 machine.

The final selected set of ray trace equations that were adopted based on optimal timing considerations is provided as a historical reference below.  The run time for the spherical version of the equation, in 1953, was 7.6 seconds per surface.

Further Reading

1. “A Manual of Operation for the Automatic Sequence Controlled Calculator,” Volume 8 in the Charles Babbage Institute Reprint Series for the History of Computing, Tomash Publishers for MIT, a 1985 facsimile reprint of the 1946 original edition.

2. James G. Baker, “The Utilization of Automatic Calculating Machinery in the Field of Optical Design,” compiled and edited by James G. Baker, Volumes 2-12, 1952 – 1954.

If anyone is aware of a copy of this report, please respond. One copy, recently discarded by Perkin-Elmer, found its way to Dr. Baker just before he died.  Does anyone know where his papers now reside?  I heard that they are somewhere in Kentucky or Tennessee.  One copy is known to exist at the Wright Patterson Air Force Base.  No other copies are known.  There were 38 copies originally printed.

For a perspective on ray trace speed and optical design, the plot below is an interesting metric proposed by Prof. Grievenkamp of Arizona.  It is a plot of the number of rays surfaces per second per dollar for computers historically used in optical design.  Additional data would be great to add.

The Lick Observatory: First Glimpses of Galaxies

Recently, a series of “best of” images for the Hubble were circling on the Internet.  One of the finalists (not sure who the judges were, but it is a nice choice) is of the Sombrero galaxy in a very nice side on view. 

Image credit: NASA/Hubble Heritage Team

It reminds me of one of I think the most astonishing items under the heading “History of Science.”  That is that in spite of the commissioning of the first modern-era reflecting telescopes on Mt. Hamilton, known as the Lick Observatory (does anyone know anything about Lick?), which from 1890 to 1928 created readily accessible images of what are now known as galaxies, no one realized that these images represented collections of stars, and they were referred to as nebulae.  At this point, I’m actually in search of whom to credit with the transition, should anyone out there know.  From my book-collecting days, I have some of the Publications of the Lick Observatory from 1893, 1908, and 1913 and similar publications for the Crossley Reflector in England, commissioned around 1891.  It is amazing to me, in the time of what we consider some of the greatest scientists, including Einstein, this went unrecognized for so long.  It is one of the things that I find most fascinating about the older books. 

Below are some of the images from this collection.  I included the galaxy that is considered most like ours: Andromeda.  In fact, I included three images, taken in 1893, 1899, and 1908 (or at least published in – more study needed).  In this period, there are many items limiting this process.  The telescope is the first factor, and in some ways the least limiting.  Photography is advancing at that point, but exposure times onto glass plate negatives are prohibitive.  Finally, the printing from the negatives to the publication is probably the most limiting.  Scanning these also adds to the process. 

Andromeda galaxy image, 1893

Andromeda galaxy image, 1899

 
Andromeda galaxy image, 1908

For this note, I’ve included the Owl nebula and the Dumb-Bell nebula, as these are true nebula that have held these common names through the years and are likely to appear again as the latest Hubble images emerge. 

 
Owl nebula image, 1908

The publications of the Lick Observatory in this period are now online (Google “Publications of the Lick Observatory”). I see that a few are on the market, for over 10 times what I paid, back when.  I’ll return with more on this topic, but, in the interim – check it out.