We regret to report that Professor Joseph LeConte Smith Jr., the Samuel C. Collins Professor Emeritus of Mechanical Engineering at MIT, died on May 7 at the age of 83. Following are tributes from his friends and colleagues.

From Prof. John G. Brisson, Mechanical Engineering Department, MIT:

Joe was a friend, an advisor and a mentor for me. He was probably the best engineer I ever knew. Joe loved to think about physical systems and argue about how they would work. He would often come up with unusual methods for building things that frequently would seem to others impossible and yet he would make them work.

We frequently spent a half hour or so in the morning discussing points about thermodynamics, teaching thermodynamics, designing cryogenic equipment and the various physical problems we encountered during our weekends. I remember long discussions on how to cut down a tree, the use of wedges, come-alongs, chains, chain falls, ropes and the specifics in the method of cutting a tree to provide a hinge so that the tree would fall in the proper direction. I remember a weekly discussion that went on for several months on Joe’s efforts to defeat a squirrel from getting to his bird feeder. It was a fight between Joe’s intellect and engineering abilities (that was, in this case, limited by his sense of the aesthetic) against the agility (and intellect) of the squirrel. It took months, but in the end, Joe’s indefatigable efforts reigned supreme.

He was always interested in devices and would take things apart just to see how they were built. On many occasions, my morning would begin with Joe coming into my office and handing me pieces of a device he had taken apart and he would ask me, in his Georgia-tinged speech, “Now what do you think that is?” or “Look at how this is designed. Why do you think they did it that way?” I learned so much from him.

I suppose if there is any one word that is associated with Joe it is “entropy.” Joe’s love of thermodynamics goes back to his years at Georgia Tech. He told me that he realized the person who was teaching him thermodynamics didn’t really understand it, so he felt challenged to figure it out. Ultimately, this put him on a crusade to make thermodynamics understandable to the undergraduate. When I was assigned to teach thermodynamics with Joe, I sat in the back of the class as he delivered lectures to our undergraduates. I had many thermodynamic epiphanies sitting in his class, only to look around at undergraduates who did not appreciate the insights and intellectual gems that rolled off of Joe’s tongue. I think much of Joe’s legacy is buried in his students who have fanned out across the world to teach the second law the way Joe would teach it.

His interest in education never flagged. In the conversations I had with him in the last months of his life, he was full of ideas on how we could extend concepts of thermodynamics and the second law to high school education.

The cryogenic community has lost one of its giants.

From Professor Yukikazu Iwasa, Francis Bitter Magnet Laboratory, MIT:

Professor Joseph LeConte Smith, Jr. was my first lab instructor in the Mechanical Engineering Department in my sophomore year (1958-1959). I had two lab partners, Richard Cummings, an Irish Bostonian, and someone named Lee, from Taiwan. Later when I got to know Joe very well, one of the memories he always enjoyed sharing with me—even at the very last time in December 2012 when we chatted during a colloquium honoring him—was about this odd foursome, Joe with his heavy Southern drawl, Dick with his Boston Irish accent, Lee with his Chinese English, and I with my broken Japanese English, trying our best to understand each other. Joe always concluded this story, smiling, “Well, Yuki, somehow the instructor and the students managed to survive and did quite well in the end.”

By chance I got a summer job in 1959, after my sophomore year, in the Cryogenic Engineering Laboratory then headed by Prof. Samuel Collins. It was Prof. Collins who showed me liquid helium for the first time, quietly boiling in a glass dewar, and taught me about superconductivity. In my senior year, Prof. Collins suggested superconductivity for my undergraduate/graduate thesis topic.

After I had decided to work on superconducting magnet technology, it was natural that I renewed, in the early 1970s, my acquaintance with Prof. Smith, who had succeeded Prof. Collins as he just began work on a superconducting generator. For this machine, he developed, among others, an innovative design that enabled liquid helium to be transferred continuously to a rotating cryostat.

In the mid 1980s, he and I, along with Professor Bora Mikic of the ME Department, traveled to Japan together. Originally from Kyoto, I arranged for the three of us to visit a few famous Kyoto temples between 5 and 7 a.m., before they opened to the public. The temples were absolutely still, with only the quiet sounds of young monks cleaning the gardens. What struck me was that these world-famous gardens and paintings—the very attractions to most visitors—didn’t interest Joe much. Instead, he was totally absorbed, and fascinated, by the intricate, and to him well-engineered, building structures, all made of wood and held together without metal. But, why not? After all, to me he was one of the best mechanical engineers I’ve ever met at MIT.

Until the summer of 2012, Joe, also a top hands-on engineer, was doing welding to repair the helium liquefier in his lab. I often visited his office, which was totally flooded with every item that ever reached his office which he saved, including more than a thousand old pink phone memos piled up on his desk, to discuss almost exclusively engineering matters. He was interested in every aspect of any device.

One day in the early 2000s, he showed me a valve used in a Toyota Camry, admiring its elegant design, which he thought would be ideal in his next cryogenic refrigerator. So, I asked him a rare non-engineering question, “Joe, what car do you drive?” Learning it was a Camry, I told my wife that evening when I returned home, “The next car we purchase will be a Toyota Camry.” Puzzled, she asked why, and I told her it was the model Joe Smith was driving. For the past 10 years, both of our cars have been Camrys.

I will miss the very gentle and kind person that Prof. Smith always was, with his broad smiling face. And of course I will always treasure his absolutely first-rate engineering knowledge and wisdom on any engineering subject. He was one of the reasons I feel grateful and lucky that I chose to study and work at MIT.

From Dr. John A. Barclay, Emerald Energy NW, LLC:

Joe’s office at MIT was an amazing collection of papers, calculations, reports and who knows what. I think the only person who knew what was in those many piles of information was Joe. He could go through a pile of papers perhaps two feet high and pick out a pertinent document! Perhaps that means chaos is in the mind of the beholder, not in the creator.

One topic I remember discussing with Joe in the early days of magnetic refrigeration above 4K (circa 1977-80) was errors in magnetic thermodynamic properties such as M as a f(B,T), Cp as a f(B,T), DTS as a f(B,T), and Stotal and Smagnetic. Joe made the observation that systematic errors in experimental data needed to be identified by simple checks on published data using various Maxwell relationships. This simple comment helped us identify and correct several experimental data sets we measured at Los Alamos.

Joe was extremely interested in novel ways to provide efficient low temperature refrigeration. He thought conceptually about thermodynamics of various gas refrigerators and had numerous graduate students investigate different ideas. In one discussion about a highly effective heat exchanger for one of his novel gas-cycle designs, I remember Joe stating the particular design would work because the enthalpy of a gas is essentially independent of the gas pressure.

One of my last conversations with Joe was at one of the CEC/ICMC conferences he regularly attended. Several of us in my team at the University of Victoria in BC were developing a novel heat exchanger to remove bulk concentrations of CO2 from biogas (~50-65% CH4 with ~30-35% CO2) by freezing it out. Joe quickly gave me a reference to a paper by one of his graduate students that showed the thermal diffusion rate was faster than the mass diffusion rate in mixtures of CO2 in various gases in vessels with walls at cryogenic temperatures (below CO2 freezing temperature at the given partial pressures).

He described experiments that the Navy had done years earlier when they tried to use a cryogenic technique to remove CO2 from air in submarines; they made solid CO2 “dust,” i.e., tiny particles that were difficult to filter out rather than bulk solid on the walls of the vessel. This was great insight from Joe that we used in the design of a novel freezing heat exchanger that very successfully removed bulk CO2 as solid on the walls of the heat exchanger. He enjoyed talking about all sorts of interesting ideas about cryogenic engineering.

From Dr. Teresa B. Peters:

I had the delight of working with Joe Smith when I was a PhD student in the Cryolab at MIT. Joe, John Brisson and I developed a novel carbonated ice cream, which Joe called snowcream. As a creative engineer, he did everything from machining parts and designing special purpose rigs to thinking through experimental results (both what we saw and what we didn’t see). He enjoyed helping me and others learn.

Joe told stories from a huge variety of past experiences, often ones that gave insight to whatever we were focused on. He shared his gifts of enthusiasm, excitement and fascination with the world. His “let’s do it” attitude and eye for first-order experiments certainly got lots of projects off the ground. In the above picture we are working on a new snowcream apparatus that we built and ran, after I finished my degree and he retired.

From Dr. Joseph V. Minervini, Plasma Science and Fusion Center, MIT:

Prof. Joseph L. Smith was an engineer’s engineer. As a former graduate student of his in the MIT Cryogenic Engineering Laborato-ry, and then later as an MIT colleague, I have had 40 years to observe, learn from him, and most importantly, respect him. When I was a student, I was amazed by the depth and breadth of his knowledge, not only in heat transfer, thermodynamics, and cryogenics, but also in fluid dynamics, superconductivity, electromagnetics, electrical machinery and almost anything else he set his focus on. And there weren’t many areas of science or technology that didn’t interest him.

Besides educating me in several of these research areas, I learned more from him by observing him in his academic and professional life, by how hard he worked and applied himself, by his dedication to teaching and the attention and devotion he gave to his students, and more importantly, by his respect for honesty and knowledge as a guiding principle of scientific research.

He was an elegant southern gentleman, dapper and well spoken, although often shy in personality. Nevertheless, he was voluble and gregarious when engaged in technical conversations. As students we often imitated his cultured southern drawl that he retained throughout his life even though he left his native Georgia as a young graduate student. He was fond of starting an answer to a probing question with the phrase, “Weellll…you seeee…” and then launching into an astonishingly insightful and well-thought-out answer.

Joe was a student of Prof. Joseph Keenan (of Keenan and Keys Steam Tables fame) and he later took over directing the Cryogenic Engineering Laboratory from Prof. Samuel C. Collins. He learned by doing, and required almost all of his students to build something by hand in the laboratory. Even if budgets were not particularly tight at times, he almost always required his students to build devices and components that could otherwise be purchased. This was an important learning experience for a young engineer.

It was also an excuse for him to help out by exercising his highly professional ability to weld almost anything, and do it beautifully. He had a well-equipped shop at home, as well. One day he regaled me about how hard he was working chipping and removing concrete from his basement wall in order to make a walkout basement. When I mentioned that there are professional companies with powerful concrete cutting saws he could have called to do the job in a few hours, he replied, “Well, where’s the fun in that!”

Joe was a unique and important figure in the development of modern cryogenic engineering and technology. He revised the undergraduate course at MIT in thermodynamics, writing a textbook with Prof. Ernie Cravalho, with a new and modern emphasis on the second law of thermodynamics. He always said, “follow the entropy.” Frankly, I always thought his own internal process was reversible by the way he ran up and down the Building 41 stairs through his long career at MIT. It was thus sadly disappointing to witness his final illness and passing, albeit done with great dignity. I will sorely miss him.

From Laurie Huget, CSA Executive Director

We at CSA are saddened at the great loss to our community from the passing of Dr. Smith. His colleagues can attest to his high standing in the academic and research community. Personally, I was impressed by his huge enthusiasm for new ideas and pursuits. He was always willing to discuss his latest project with me when we met at conferences and in conversation he gave me his undivided attention. He was very generous with colleagues and truly a gentleman. We will miss him greatly.

From Chuck Tower, Linde LLC:

We at Linde are extremely saddened by the passing of Professor Joseph Smith, head of the Cryogenics Department at MIT. My colleagues and I have been working closely with Professor Smith for many years. We will miss his enthusiasm and passion for very important work in cryogenics, particularly liquid helium recovery systems. More than that, however, we will miss him. We had a great working relationship.

From Professor Sangkwon Jeong, Korea Advanced Institute of Science and Technology:

Since I first met Prof. Smith in 1988, he has been my continuing teacher and mentor even after I left the Cryogenic Engineering Laboratory at MIT in 1992. He possessed a warm personality and great modesty and was always approachable with a smile and lots of fascinating ideas (sometimes he called them his crazy ideas). His intellectual curiosity and practical valuable knowledge was everywhere, not only in mechanical but also electrical engineering.

As one of his PhD students, I remember we used to call him “an angel without wings” because he never lost his patience when we were lousy enough to cause some trouble with clumsy work. As an academic colleague, I remember he kept giving me constant advice and valuable lessons whenever I saw him at conferences or when I had opportunities to visit MIT. I still have a vivid memory of when he was helping me construct my experimental apparatus, which was seriously testing his welding skills with many challenging components. It was really a tough job, but he never complained about my design. He seemed in fact to enjoy doing some challenging work, which encouraged, motivated and inspired people around him. I believe his legacy in the cryogenic engineering field will be forever appreciated by successors, especially for superconducting generators, magnetic refrigeration and cryocoolers.

As an educator, he always emphasized hands-on experience as well as creative ideas on thermodynamics. His spirit of motivating students to grasp difficult and complex thermodynamics concepts was reflected in several house-made class demonstration devices, including triple state and critical point visualization apparatuses. His enthusiasm for new knowledge and intellectual capability seemed never to fade away, even in his 80s.

When I visited his house the last time in 2010, he was happy to show and explain his recent project in his personal machine shop. And then we kept talking (I listened most of the time, in fact) about different aspects of the second law of thermodynamics that night until my wife was nudging me to leave. Surely, it was not an interesting topic to my family members. He was waving his hand when we drove out of his Concord property. I regret that I was not aware of the fact that it was the last time I’d see him. I always believed he would be alive giving us constant admonition.

From Robert Hendricks, NASA Glenn Research Center:

Joe was a fantastic person. We worked together well on a variety of subjects. Always helpful and always alert to the needs and suggestions of others. A great contributor to the cryo labs at MIT, building and running SC systems. My condolences to Joe’s family and greater family of students, faculty and industrial partners. Joe will be missed and still life is everlasting for him…Amen. Sending an abundance of blessings, prayers, thoughts and healing grace.

From Dr. Glen McIntosh, McIntosh Cryogenics:

At the 1983 CEC in Colorado Springs, Colorado, Dr. Joe Smith received the Samuel C. Collins Award. The presentation was made by Sam Collins himself. After some preliminary words, Sam said, “This is no ordinary Joe Smith.” As usual, Sam hit the nail right on the head. Dr. Joe Smith was certainly not ordinary.