Graduate experience 1951-55

by Martin Goldsmith (MS 52 ME, PhD 55 ME)

Toward the end of the summer I made a few trips to Pasadena to start making arrangements to move there. The graduate office had some listings for living quarters. At that time there was no graduate dormitory at CIT. There were a few rooms in the ‘Old Dorm' over the coffee shop. They were pretty poor. I was directed to one private home where there was a guest room for rent. It turned out to be about two short blocks from campus, a lovely spacious Spanish-style home owned by Dr. Ruth Tolman. She was a clinical psychologist who had trained with the famous Prof. Tolman of Stanford, and married his brother, the world-renowned physicist Richard Tolman. He had died several years before, and Dr. Tolman was renting out the guest room behind the house. It was a separate structure, with a one-car garage. The room had only a bathroom, no other facilities, but opened out onto the garden. It was perfect and I jumped at the chance to live there. It was to be my home for the next four years.

A notable feature of living there turned out to be the constant stream of visitors. She knew most of the world's famous physicists, and when they visited Pasadena, they stayed at the house. We're talking about people of the stature of Oppenheimer, Rabi, and others. I'd get a chance to meet them once in a while, and it is a pretty heady experience just to lay eyes on such people. I have to admit to being star-struck in the presence of Oppie, for example. I'll never forget our most memorable last meeting. He greeted me and asked "Where can you get some laundry done around here?" Mrs. Tolman's best friends included Mrs. Bacher, the wife of the chairman of the physics department at Tech. So I'd see Prof Bacher in the backyard now and again helping with chores. Seeing the physics chair with his suspenders down, driving a fencepost is a not to be forgotten sight. Of course he got to know me, and it always puzzled my physics student friends when we were walking on the campus and Bacher would greet them with "Hello, boys" and me with "Hi, Marty".

I had enrolled with the expectation of doing one year of work for a masters degree. As it turned out, I was so delighted with the place, the ambience, the quality of the profs and the students, that by the end of the year I resolved to try for a Ph.D. More math was required (a lot more) and I was fortunate to have as a prof for applied math a recent graduate named Forrest Gilmore. He was just a whiz at teaching a mathematically-challenged fellow like me what differential equations were all about. Whatever skills I ever came to possess, I owe to the foundation he gave me. While courses in such basics as math usually used textbooks, many of the courses did not. The reason was that Caltech tended to be on the leading edge, and the course material often led to texts in later years. So it was with Jet Propulsion, taught by Frank Marble, a JPL pioneer and a very fine prof and person. His lectures consisted of detailed analyses of the thermodynamics of propulsion systems. After every lecture I would very carefully copy the notes, and they were so clear that I could probably understand what was done even today. Another course was Chemical Problems in Jet Propulsion, taught by Sol Penner, who eventually became my thesis advisor. His notes I do not have, but that material was included in a text he wrote a few years later, a copy of which is with my other papers and books (my thesis work is included in that book). That is often how it went at Caltech – last year's research is this year's lecture material. Compared to the jet propulsion and math courses, the mechanical engineering courses I took seemed pretty dull. I did take a great course in philosophy taught by Hunter Mead. He was a fine fellow, and an accomplished organist. In fact his whole house was essentially a pipe organ!

Grades per se didn't mean much at Tech. What seemed to be important was what the faculty thought about your potential. At the end of the year I got my MS and applied to continue in grad school. You can imagine my delight when I was accepted and was granted a Guggenheim Jet Propulsion Fellowship! (Newspaper clips and other papers are in the archive.) First off, that was a real ego-booster, and after a year of CIT one could use a little of that. But it also included tuition (then $600/year) and a tax-free stipend of $2000 for the year. That more than covered my expenses, and I actually started to save a little money while I was going to school.

That summer I got a job at JPL, doing some research on heat transfer in boiling fluids. This was arranged for by Prof. Rolf Sabersky, whom I had approached about doing thesis work under him. The topic had been around a while, and good experimental methods had been devised, which I was going to implement. The pay was $400/month, which I thought was fantastic when one was working essentially on one's thesis.

Looking back now I realize that making a thesis out of what was already established might have been a difficult thing to do. Anyway, I enjoyed JPL. The staff there were very good, and made me feel at home. I carpooled there with a student named Ed Zukoski, who was also in jet propulsion and doing a thesis for Prof. Marble. Ed was a very bright and hard-working guy, and he later became a prof at Caltech. He died a few years ago, but our friendship lasted all these years.

As the summer ended and I went back to the campus, I was approached by Prof. Penner, who proposed to me that I do a thesis under him, working on the problem of the combustion of single drops of fuel, doing experiments and developing theory. It would involve the construction of a rather massive test chamber, capable of operating at elevated temperatures and high pressure. He had a contract with the Army Office of Ordnance Research to do the work, so financial support was not in doubt. It sounded like a winner to me, so I cleared my change of heart with Rolf Sabersky, and committed to Sol Penner. Now Rolf was a very fine person, and we remained friends until my last contact with the campus about fifteen years ago. However, linking up with Sol Penner was a opportunity whose value I did not realize at the time. Unlike many of the profs, who seldom met with their thesis students, I saw Sol at least several times a week. I was only his second graduate student, the first having already finished, so I had a lot of his time and attention. As the years passed, he left Caltech for a period of government service, and then ended up at UC San Diego, where he remains. He became a very senior leader there, much beloved by a long list of graduate students and fellow faculty. Brita and I were privileged to attend his 70th birthday party a few years ago, and the outflowing of love and admiration for the man was impressive. I contributed my share.

One of the benefits of being an assistant or a fellow was the assignment of office space. Rather than having to return to my off-campus room to study, I now shared an office with telephone, etc. This made much more efficient use of time. Moreover, a prof could find you instantly if he wanted to see you. Sol wanted to see me a lot. This year I shared the office with Gordon Macloed, an older fellow, and a very proper citizen. We got along quite well, but he left at the end of the year. The last two years my office mate was Sedat Serdengecti, a Turkish man about my age. He was a very bright guy, and a fine gentleman. I learned to love and respect him. After graduation he voluntarily returned to Turkey to do his military service, and then came back to the USA where he became a prof at Harvey Mudd, where he remained until retirement. (An interesting side note – when Brita and I met Rick and Susie McWilliams down in the Sea of Cortez, our friendship got off to a good start when Rick revealed that Sedat was his mentor at Mudd, and I told him of our prior relationship.)

There were many very interesting and impressive people on the faculty and among the students. One who has always stood out in my mind was Paul MacCready, who was then a post-doc in aero. He is the fellow who developed the Gossamer Condor and many other incredible flying machines. Another one who impressed us all greatly at the time was Moshe Ahrens, who was reputed to have been a gun-runner for the Irgun during the wars of Israeli independence. Later he became head of Israel Aircraft Industries, and Minister of Defense in the Likud government. There was Clarence Allen, who has become one of the best known seismologists in the world, and whom we often were with at dinner. The list of those who became well-known academics is endless.

Our working habits were pretty routine. In the office, or class, or lab, by 8AM. Half-hour or so for lunch at the ‘greasy spoon' (cafeteria), an hour for dinner at the Athenaeum, and back to the office until 10PM. Pretty much twelve hour working days, but less on weekends, maybe fifteen hours total. Dinner at the Ath was very enjoyable. Unlike today, the dining room catered to the grad students at night. Dinner was simple and cheap. We mostly ate a large round tables, seating eight. We generally were a mixed bag of disciplines, so all of us became familiar with the technical and people problems of the different departments. Sometimes a faculty member would stop by, and we often had visitors, who were staying upstairs in the guest quarters. These were often people of great distinction, even including Nobel Prize winners. These distinguished people would sit down and often started asking the students about their work. It is for reasons like this that I think Caltech offered an education like no other place. I do not think that the same conditions prevail today, but the education remains excellent, without doubt.

Courses continued, in mathematics, physics, and engineering. Julian Cole was a memorable instructor in applied mathematics. He tended to lecture on what interested him at the time, so things had a little researchy flavor. In his last final, the problems were extremely difficult. In fact, I couldn't finish even one of the four or five. I left my office to return the test paper, very dejected, and found my fellow students with long faces. None of us felt we had done anything with the exam. At the next meeting, we challenged Julian to show us the secrets. He started off, and lo and behold, he couldn't do them either!

I elected a minor in physics, and took one course from Robert Leighton, who had to be one of the finest instructors I have ever had. Later I took a course in mathematical physics from Robert Christy. I was certainly not the brightest bulb in the chandelier in that one! I have later found out that Christy had stood up for principle in an encounter with Edward Teller, and I will forever respect him for his intellect and character. He later became the Provost, I believe.

At the end of the second year, I was granted a second year of the Guggenheim, so again, my financial status was good. Additionally, Sol Penner volunteered to pay me the same summer wage I had been given by JPL the prior summer. Remember, this work was almost entirely devoted to my thesis. The same sort of situation prevailed in my final year, when there was no Guggenheim (they were for two years, max). A grad student could only be listed as working half-time while registered, so my pay was half-pay during school. That was plenty to live on. Penner took very good care of his grad students.

Among the other requirements for the Ph.D. at that time was foreign language. German was required, and another major language was the choice of the student. After I was admitted to the Ph.D. program, I passed French by examination. I walked into the proof's office, he handed me a French text, and said "read". I started off translating away, relying on my high school training. After a few minutes he said "OK" and signed my paper. German was another story. I didn't know a word of the language, and had no time to take a course in it. So I elected to translate a rather lengthy paper written by a well-known German engineer on the topic of combustion. I worked on that bloody thing every night over a whole summer, relying on a dictionary, sweat, and Rolf Sabersky, whose mother tongue was German. When I would get absolutely stuck on some phrase, I would consult Rolf. He would often mumble about the author's tortured syntax, and once in a while he would be stuck too! Anyway, that task ended, and actually I published the translation as a RAND document after I went to work there two years later.

In the third year I took several courses because they seemed interesting, but were not central to my field of study. They were interesting, but my taking them had some interesting consequences in my final year. They included such topics as solid mechanics, taught by the famous earthquake engineer George Housner , and control theory, taught by Tsien. A great deal of my time went into constructing my lab apparatus. The detail design and major construction was accomplished by the Caltech engineering shops. The smaller parts I made myself in the ME machine shop. I had established my bona fides with the faculty member in charge, Pete Kyropoulis, in my first year, and it was important to do so. If he approved, you had the run of the shop, but woe to him that screwed up! Another facility that I used was the photo lab, presided over by Don Clark. Same caveats.

Sol had started me off on my research problem by giving me copies of several British reports on the burning of single drops of fuel. The model was very plausible, but the author, Godsave, had to assume values for several variables, including the flame diameter and temperature. Sol wanted me to see if I could calculate those values, rather than just use estimated values. I got to work on the problem, and it seemed to me that all the information necessary to make the calculations was available, at least for the very simple geometry of the model. As is pretty common with problems of that nature, you fool around for a while, then see a way of writing the equations, and then you bang on them with different methods, and finally a solution appears. When it is all written down, it looks very simple, and everyone, including the analyst, says, "well, that wasn't too hard, was it". All solutions look easy once you see them. What you don't see is all the incorrect approaches that went in the trash. Anyway, what I had calculated was a complete analysis of the simple droplet model, from first principles. So, by the time I was in my third year, I had completed the theoretical part of my thesis research. Sol had me write it up for publication, and it was published in the Journal of the American Rocket Society in the summer of 1954. Copies of this and other papers I will mentionare in my archive folder. It is typical of Penner's generosity of spirit that he insisted that I be the lead author of the paper. It was not common for professors to do that, especially if they were young and still making a name for themselves.

The big job then was to get the furnace working and make experimental measurements to corroborate the theory. The shop finally finished their work, and it was a monster. I don't remember how much it weighed, but it was solid stainless steel, and had to be many hundred pounds. There were quartz windows through which you could photograph the burning droplets. I had purchased a used Eyemo 35mm motion picture camera to record the data. It was not a usual scientific instrument, but rather a professional movie camera. I used the "Eyemo" movie camera, and a high speed scientific camera which moved the film at a very high speed continuously, with shuttering provided by a high speed repeating strobe. There are photos of all this with my thesis. I would photograph the drops as they burned, and by measuring the diameter of the image as it became smaller, I could calculate the burning rate. The first experiments, conducted at room temperature and pressure, gave results which were embarrassingly close to those predicted by my theory. Both Sol and I thought we would be accused of fraud! We found it difficult to make the crude injector I had constructed operate at elevated pressures and temperatures, so that part of the theory was never adequately tested. We did explore the influence of atmospheric oxygen content, and again, the agreement with theory was good. This work occupied the summer of 1954. A paper on the experimental results was published in the JARS in early 1956 (copy in folder), and of course all the details are in my thesis, a copy of which is in my archive of documents. Penner insisted that I be listed as the sole author of the paper, a most uncommon and generous act. The paper also shows a photograph of the experimental contraption.

Sol was happy with the work, and had me start to write it up. However, as there were months left before the end of the school year, Dr. Tsein (more about him later) wanted me to do a different kind of analysis of the problem. Some sidekick of his, a Dr. Kuo, made the almost preposterous proposition that the correct model was not a diffusion flame at all, but a thermal flame model. My readers will not grasp this point, but the whole concept is rather mad. Tsien insisted that I analyze it. Penner said he would have nothing to do with it, as he considered it absurd on the face of it. But I was stuck, and I went to work. I couldn't make any sense of it – couldn't even formulate a decent model (equations). Tsien kept sending me back to try again. Finally, I reverted to arguments based on first principles, and was able to show that the problem as formulated was impossible. With much grumbling, even Tsien was forced to agree, but then he insisted that I include this mess in my thesis. Sol blew his top, and swore he wouldn't sign the thesis! Oh, the life of a grad student. In the end, the analysis was in , and Sol signed off. It became ever more clear to me that Tsien and Penner did not get along very well, and the student is of course caught in the middle.

I was scheduled to take my oral examinations early in the Fall term of 1954, so I devoted a lot of time in the summer to studying topics which I expected would be covered. This first oral was to cover the course work, but not the thesis. Some of the profs discussed with me the sorts of things they would want to discuss; others said nothing. I paid a lot of attention to my core subjects, thermodynamics, heat transfer, combustion, jet propulsion, and of course, physics and applied mathematics. The committee included seven faculty, Tsien, Penner, Marble, (for jet propulsion) Rannie (for thermodynamics), Cole (for applied mathematics), Leighton (physics), and Kyropoulos (for my major, mechanical engineering). I was the first JP victim scheduled for the year. Unbeknownst to me, the last student to be examined at the end of Spring had not done very well, but they let him go as he had to report for active military duty that summer. That really galled Tsien, and he went in with the position that the next students were going to have to do well to pass. My exam was going along with the usual ups and downs. (They were usually three hours long.) Kyro was easy, Marble was straightforward, Rannie asked me an almost philosophical question which baffled me, Penner was gentle, as might be expected, Cole was difficult, but not impossibly so, and Leighton asked most interesting questions, which I was fortunately able to ace. (One was, "If you look at beer, it appears brown, but the foam is white. Why is that?") Then came Tsien. He started off on his course in control theory, which I had taken because it was a new and very researchy topic, but which was far outside my main interest. The mathematics were not those which were customarily used in my line, and it wasn't long before I was floundering around. Time ran out, and I was dismissed. After some time, the committee filed out, and Sol told me to come with him to his office. He was very kind, and the message was that I hadn't failed, but I hadn't passed. Tsien had said that I could do better, so I would do better, and I was told that the process would be repeated in six weeks. Penner assured me that I would be getting my degree on schedule, and not to worry – just do better! Within a short time I had conversations with most of the committee. Kyro was boiling mad. He described Tsien in language unfit for a family newspaper, and proceeded to tell me exactly what he was going to ask next time. Others were studiously non-committal. Overall, I was worried, but not devastated. Some other students, due for examination later, were extremely concerned, and probably lost more sleep over it than I.

I devoted the next six weeks to studying control theory. Came the new examination, and it proved to be most interesting. Kyro asked exactly what he said he would; Marble asked very little, as I recall. Cole pointedly said that he was satisfied the last time, and Leighton said he had no further questions. Clearly battle lines were being drawn. There were several questions and discussion, and then it was Tsien's turn. He started at EXACTLY the same point we had left off. But this time I had it wired. Rattled off the analysis of that particular point, dotting the i's and crossing the t's, and Tsien was satisfied, showing his enigmatic smile. I suppose he had made his point.

As Spring came around, life became a matter of tidying up details, like writing up the thesis and having it prepared as an archival publication. To a generation raised with word processors, the task of producing an error-free typed manuscript in those days would seem like Catch-22. One also defended one's thesis in an oral exam, but that was not really a problem. The student ought to know more about his subject than any other person alive, and if you had a problem defending it, that would really be shame on you and shame on your thesis advisor. The attention of the upcoming graduates was turning to where we would go next. In the sciences, most were focussed on academia. Some of the engineers were also inclined that way, but most were interested in industry. We were all of us anxious to be gone. In those days, four years was the normal time for post-graduate studies. Those that got out in three were considered geniuses; those that took five were considered unlucky.

This was the time when the space and missile program was just getting underway, and all of government and industry were seeking technical graduates. All the major players came to Caltech to interview. We were advised to speak to as many of them as we could, with the reasoning that this would be the only time in your life when you could easily do so. I knew I wanted to be in the rocket racket, but I also spoke to other sorts of places, such as oil companies. Actually the places that tried to make it most attractive to me were Esso (Exxon) and GE. Esso wanted me to try to find a way to burn bunker oil efficiently. This low value by-product of the refining process could end up making them a lot of money if it could be used in high-performance applications. They promised that my financial future would be assured if I carried it off. But nice as they were, that isn't what I wanted to do. My prime interests were in the local rocket companies, Aerojet and North American Aviation. I was interviewed by the new company, Ramo-Wooldridge. They wouldn't say what their work was all about (it was to manage the Air Force missile program), but we all knew anyway. They described the job they wanted me for, and I was actually appalled, as I didn't consider myself to have the experience needed and told them so. That pissed them off, and they even called Tsien to complain about it.

In the middle of my interviews in Pasadena and around the country, Julian Cole asked me if I knew anything about RAND Corp. I didn't, but he was a consultant there, and told me a little of what they did. He said that they were looking for one or two new graduates, and would arrange an interview if I was interested. I talked to them, and the job seemed absolutely fascinating. They basically were doing planning work for things that were well beyond the present state-of-art. Anyway, I expressed interest, and they made me an offer. I still had other offers coning in, and feeling it was only proper to do so, I told RAND I felt obligated to wait for the others, although I told them I was quite sure I wanted to work for them. They said they had not hired a new graduate for a long time, and were unfamiliar with the market. Wanted to know how their offer stacked up. I told them it was somewhat lower than others, but that would not be a deterrent. They promptly upped the ante. Anyway, in a short time I formally accepted their offer, and spent some time before graduation looking for a place to live in West LA. Settled on Westwood, and the Monday after the Friday graduation, I reported for work.

At this point I ought to say something about Dr. Tsien. He had been a graduate student under von Karman at Caltech, and with others was in the pioneering group that started CIT on its way in rocketry, first at the campus and later at the new Jet Propulsion Laboratory. He was a Chinese national, with an undergraduate education in China. After the war he went to MIT for a while, and then returned to Caltech, and was now the Guggenheim Professor of Jet Propulsion. He was extremely good at applied mathematics and had a good physical sense of what went on in natural processes and engineering devices. He was also an abrupt person, often rude, and was considered arrogant by many. We students had enormous respect for him, but very few liked him. Many faculty disliked him. In about 1950, he attempted to return to China for a visit, to his family and former colleagues. He was stopped at the dock, as it were, by the FBI, and his baggage was seized. He had many technical papers with him, and he was accusedof trying to take secret material to China. My understanding was that there were no classified papers among his stuff, but owing to his association he was suspected of being a communist and perhaps a spy. He was ordered held in the USA, but the INS at the same time had an order to deport him. So he was in limbo, but it didn't affect his ability to be a professor. He could not consult with industry or government, of course, as many of his colleagues were able to do. Shortly after I left Tech, the restraining order was lifted, and he returned to China. There he is reported to have been the leader of their missile and space effort, and some say he was influential in their nuclear program as well. In a biography of him written by a Chinese author, his life in China was outlined, and I would say in mostly unflattering terms. I cannot attest to the validity of any of this. I did return to see him before he left, just out of respect, and he said he had no quarrel with the American people, who had treated him kindly, but he held our government in contempt. I think most Americans have the same reaction to the Chinese people and their government. Looking back, I think his hard ways were not harmful to the students, but may not have done much good, either. It certainly kept the students from having that devotion to him that other men, like Penner or Marble, could enjoy. I would not care to see him again.

Last updated 4/12/07.

Christopher E. Brennen