by Pepper White
After sunset the office light made the window a mirror, and I saw myself beside the computer and imagined the Newsweek picture of "MIT's White," the brilliant young engineering professor whose research is solving the world's energy and environmental problems. I'd wear a V-necked pullover, lean back in the desk chair, and have my hands clasped behind my head and elbows out. The bookcases in the background would be full.
Back to the balloon. Time to refer to the equations and the drawing. Greene had said I need to think of the flow of information in any algorithm (solution method) I write. That means I need to take my three equations and arrange them in an order so that the result of one calculation will feed into the unknown side of the next calculation, that answer will feed into the unknown side of the next calculation, and so on. This is how I will march through time and blow up my balloon.
Mr. Apple's logo is an apple with a rainbow on it and a bite out of it. The apple is the fruit from the tree of knowledge. The rainbow is the promise that one flood was enough. A bite sounds like a byte is 8 bits. What does it all mean?
March 21
The office is home base for graduate students. Mine was upstairs from the lab, near those of Chet Yeung and West. There were five offices at the end of the hall. Ari's was on one side of mine. One of Ari's office mates was a Russian who'd left the Soviet Union in '58 with his family. Scott Rogers was on the other side of me. Ben Radovsky was across the hall.
Steve Geiger shared the office with Ben and Mary. Mary had set up a fish tank, and they also had a coffeepot and a big drafting table in the center of the room. Often those of us from neighboring offices would walk in, make a cup of tea or cotl-e, pull a chair up to the drafting table, and talk camshafts. Mr. and Mrs. Tung from Beijing were next door. They often boiled seaweedlike materials that gave off strange smells in their adapted electric coffeepot.
The office becomes the core of your sense of community. Every department is divided into subspecialties. Anycue you meet in a class may be in a different group, so you have no reason to see him or her outside or after the class. There may be an occasional chance encounter on the infinite corridor or in the student center coffee shop, but other than that, you lose contact. It's part of why the institute is such a lonely place-the knowledge and the students are segmented.
I chatted with Mary while drinking tea at the drafting table, and West interrupted.
"Mary, we need to talk about the fuel system. Paul's not pulling his weight in the experiment and--
The phone rang.
West picked it up, answered, "Mary's in a meeting now. Call back later," and hung up.
Mary's face turned red with rage. She stood up and said to West, "Don't you ever do that again. I don't care who you are or what kind of power you have. You have no right to intercept a call like that."
"Well, I think I do," West said. "What do you think, Pepper?"
It was a scummy thing to do. You have power, and, because I'm on probation I need all the powerful friends I can get. "No comment," I answered.
West continued. "Well anyway, Mary, I want you to cover for Paul. We've got to keep the project moving."
After West was out of earshot Mary said, "Why didn't you stick up for me? I thought you were my friend."
"You did pretty well for yourself. I didn't want to get involved. Besides, he's keeping me out of debt," I said.
"Well, I guess we know where your priorities are. Thanks. Thanks a lot."
"Hey, look. I'm sorry. I'll try to make it up to you someday."
March 25
La chasse aux fuites. The search for leaks. I'd fired the RCM at a compression ratio higher than ever before attempted. That was the good news. The bad news was that the pressure at the top of the stroke was about half as high as needed. That meant there were leaks.
Machinery leaks when two pieces of metal are next to each other and the pressure inside the machine pushes out whatever liquid or gas you're trying to compress. I asked Chet Yeung, the new assistant professor, who was gradually becoming my adviser as West was preparing for the start-up of his company on Route 128, for help.
Chet knew everything. Born in Hong Kong, at age five he had built Heathkit radios. One summer during high school he worked as a machinist; another summer he worked as a draftsman in a machine tool plant. Yet another summer he worked as a computer programmer. This was all before he graduated from Cal Tech with an applied mathematics degree. Chet wanted to be a mathematician, wasn't quite good enough to be a great one, but was well on his way to becoming a great engineering professor.
"So you have to put some O-rings in," he said. "And you have to look at every surface to see where the leakage paths might be and put them there." Chet pulled one of the ten notebooks off the bookshelf behind him and turned to a page in it that described O-ring design. An O-ring is a skinny rubber donut that fits in a groove and prevents the air or water from leaking.
Chet made a quick sketch of the groove dimensions, made a list of the O-ring sizes, then sent me down to Nick to have him machine the grooves.
Nick was milling a part, and "Begin the Beguine" was playing on the radio.
"You hear the news, Cap'n?" Nick asked. "A plane just took off from Miami and had to turn around. The mechanic who rebuilt the engine forgot to put some O-rings in and the bearing oil almost all leaked out. Imagine that. 'S lucky no one got killed."
O-rings are important.
March 29
All O-rings in place, it was time for another firing. The shaft was in its backmost position, held in place by a little piece of metal in a slot in the back of the shaft. There was a pendulum, basically a pipe with a hinge on one end, at the back of the shaft. The idea was to raise the pressure in the tank and then let the pendulum swing into the back of the shaft. The little piece of metal was strong enough to avoid breaking with the pull of the shaft from the air pressure, but not strong enough to hold when the pendulum hit it. The pendulum was the pipe that broke the shaft's back.
Chet, Scott, Nick, and I were in the test cell when we tried the first firing with the new O-rings in place. The shaft was set up and I opened the valve to let the driving pressure on the tank build up.
The air made a hissing, ringing sound as it filled the tank and the gauge climbed up through 10, 20, 30 pounds per square inch (psi). The first thunk noise came at 52 psi. I closed the valve. My pulse was up to 90.
"What was that?" I asked.
Nick answered from the back where he was holding the pendulum. "I remember that one, Cap'n; that's the first one. Nothing to be afraid of. The metal's just adjusting itself."
"Keep raising the pressure," Chet said from across the cell where he was adjusting the brightness of the oscilloscope. The oscilloscope was just like the ones I'd seen before in Weare's lab, basically a TV set with only one channel, or trace. Its beam of electrons went from left to right on the screen. As the pressure rose in the RCM's cylinder, the electron beam would be deflected upward and make a glowing graph of measured cylinder pressure versus time. The oscilloscope was our eye on the world of the very fast, the things that happen in small fractions of a second.
At 90 psi there was another thunk and the tank started to creak.
"That's as high as it was ever run, Cap'n. Any more pressure is unexplored territory," Nick said as he crossed himself with his free hand.
"Let's raise it to 110," Chet said. "There's still plenty of safety factor at that level. We'll need at least that much pressure to push through the pressure the cylinder will develop with the higher compression ratio."
The loudest thunk yet came at 105 but nothing blew up, so I kept going to 110 psi. My pulse still rose with the pressure. I closed the valve.
"Ready, Nick?"
"And waiting, Cap'n."
Nick let go of the pendulum.
It was over in an instant like a gunshot. The trace on the oscilloscope bobbed up and down.
"Looks like good news and bad news," Chet said.
"What do you mean?" I as
ked him.
"I think there are no more leaks, but we need more pressure. The piston went forward, bounced back, went forward, bounced back, and as the compressed gas cooled, the piston finally made it all the way forward."
All in half a second.
Chet added, "We're going to need a stronger tank, maybe a new starting mechanism, maybe a new shaft. Let's take a look at the shaft. Nick, do you have your micrometer handy?"
"Yes, sir, Professor," Nick said.
After we pulled the shaft back into prefiring position, Chet tightened the micrometer on the pendulum end of the shaft and then moved it down the shaft to the back of the machine.
"That's what I was afraid of," he said as the micrometer became looser and looser along the length of the shaft. "We'll need a new shaft, too. This one has been stretching with the higher force, so it becomes longer and skinnier. Before it was like it was supporting a Toyota; now it's supporting a Cadillac."
New tank, new shaft, new starting mechanism. How many months will that add to my term in the cell?
April 20
Spring was fully with us, consistently warm at last. The daffodils were out, the sky was blue with some big breezy clouds, and the sailboats were on the Charles again. I felt newborn when I met Mary in front of the Green Building.
"Did you hear about Gyftopoulos?" she asked.
"No. What about him?" I said.
"He had a heart attack."
So he's a human being after all. I wondered whether he'd had a near-death experience, whether he'd floated up above his body for a few moments in the valley of the shadow of death and said it's not time yet-there are too many more students to teach-or whether he'd just blacked out and there was nothing but the pain in his chest.
"Is he OK?" I asked.
"Yes. I heard he just got out of intensive care. He'll be in the hospital for a couple of weeks, but they think it's a mild one. He'll probably have to take off some weight and quit smoking," she answered.
"I sure hope he pulls through. He's a good man. By the way, what ever happened to your dorky lab partner? I haven't seen him around the lab for a while."
"He was booted out. They just sat him down and said to him that he couldn't do research and now he's gone. I think he's doing some kind of computer consulting or something," she said.
These guys play for keeps. If you can't produce, you're history.
April 22
I bumped into Jim Stuart going down the infinite corridor. The Ivy League knowing look had faded, had been beaten out of his eyes by all the 50 percents he'd scored on problem sets and exams. His calculator was on his belt.
"What's the deal with the calculator, Jim?" I asked.
"What about it?"
"It's on your belt. Don't you remember? I bet you would have thrown spitballs at anyone in your high school who did that," I said.
"Oh," he paused. "Yeah. Well, it's actually a really convenient way to carry it. The case protects the calculator, and it frees up my arms to carry books and other things without worrying about dropping it."
Function is greater than form.
May 12
"You made a good start, and I would have expected more progress by now," Greene said.
"I need some more time, sir. Things should ease up in the lab during the summer, so I should be able to finish off the balloon problem. Besides, this whole business of computer modeling is kind of new to me. I'm just totally stumped on how to make the equations flow."
He said, "It's important that you figure this out for yourself. I could teach you, but there's a big difference between learning and being taught. You know, it's sort of like trying to learn the language in a foreign country. Say you go out to the market and you want to buy something that's not on display-apples, for example. If you know 100 words in the language, you'll use all of them trying to communicate that 101st word that you need. In the process you may learn a few more words from the shopkeeper. When you finally hit on that 101st word, and you're taking a bite out of the apple, you've internalized the knowledge, and you'll never forget it. Capisce?"
"So what do I have to do to get a B?" I asked.
He answered, "If you can make your balloon model work as you've now set it up and produce meaningful results with realistic pressures and elasticities, I'll give you a B. I'll give you till the end of the summer to do that. If there's any time left after that, you can make the model a little more realistic and I'll give you an A. This isn't related much to energy engineering but it's a good problem and that's why we call it independent study. By the way, have you come up with any more examples of entropy?"
"Uh, yeah. I've thought of a couple more," I said. "I used to race bicycles, and the key to doing well in races was always to be in a 15-man breakaway from the 100-man field. Once the breakaway is a minute or two ahead of the pack it'll never be caught. The guys in the break work together smoothly, and you only have to fight the wind one-fifteenth as much as you would if you sprinted off the front of the pack by yourself. The pack generally can't organize itself to bridge the gap, so the breakaway's lead just gets bigger and bigger."
"Umhmmm," he answered. "So the flow of information as to how to share the wind load more efficiently is more efficient in the breakaway than in the pack. Better information flow means better organization and lower entropy. I like it. What's the other example?"
"I read in the Globe that Boston is windier than Kansas, but Boston isn't as good a place for windmills because the wind direction is always changing. So a windmill in Boston would spend a lot of time turning to face the wind, and by the time it faces the wind, the wind direction may have changed again," I said, and drew a picture on his blackboard.
"So in the limiting case," Greene added, "the windmill will turn back and forth and never face the wind long enough to produce any power. The windmill turns, but that turning results in no power delivered to the propellor. You're beginning to internalize entropy."
May 15.
Heywood's exam was in Room 1-134. I made a point of arriving early, finding the janitor to open the locked door, arranging my books and notebooks, finding a wall outlet, plugging my borrowed calculator into the wall outlet, sharpening my twelve number two pencils, flossing my teeth. Everything was in order at 1: 15, fifteen minutes before the exam would start.
My scores on the four problem sets and the term project were above average. I was definitely in B territory, unless, of course, I choked on the final. A well-below-average score would put me into C-land and onto the street.
I went outside to sit on the Henry Moore sculpture in Killian Court. I tried to clear my thoughts, to be receptive to the inspiration I'd need to pass. The fresh-cut lawn smelled sweet when I closed my eyes.
At five minutes to launch I went back to the classroom. Ben Radovsky and two other guys were standing next to my desk and laughing. A little closer, I saw my calculator broken on the floor, and the twelve number two pencils at rest randomly underneath the neighboring desks.
"What happened?" I asked, panic-stricken.
Ben said, "I didn't see your calculator cord and I tripped over it."
There was no tone of apology in his voice. Obviously, my calculator setup was a faulty design and had presented a hazard to the public. Never mind there was less than a foot between my desk and the wall outlet; never mind that any thinking human being would have walked around the other way.
"Yeah, and what's so funny about that?" I asked him.
"Well, you've got to admit it's kind of funny that you set things up so carefully and tried to plan it all in advance and then this happens. It's the kind of thing that would happen to Woody Allen," Ben smirked.
"Well, I'm screwed without a calculator," I said. "Do you have an extra one?"
"No, I only brought one, and I need it."
Ari tapped me on the shoulder.
"Here, my friend," he said. "I brought two extras. Don't worry; it's fully charged."
"Oh great, thanks a lot. You've saved my life," I
answered, wanting to give him a hug. "But why'd you bring three?"
He answered, "It's just one of the principles of good engineering-redundant systems."
C H A P T E R
10
In Control
Schedule:
Summer '82: 2.023 System Dynamics and Control (Miller)
2.999 Independent Study (Greene)
2.996 Thesis
In early June Gyftopoulos walked out of the Walker dining hall. He looked a good twenty pounds thinner, and he walked slowly, more tentatively than before the heart attack. He'd wakened up to the fact that he wasn't going to be at MIT forever; you could see it in his eyes. For the first time I felt I had something he didn'tfifty or sixty years ahead of me. When he said hello, his voice was a little tentative, like his walk.
"Yes, I'm recuperating fine, Pepper. Thank you for asking. I'm starting by coming in to work two days a week, and gradually I will work back up to five."
"It's good to see you back, sir."
"It's good to be back."
I squeaked out the B in Heywood's class. It wasn't that my performance on the final was stellar, but that over half the class's performance was at least as murky as mine. So murky that Professor Heywood, in the critique he handed back with the exams, wrote, "While some of you showed complete mastery of the concepts presented, many of you did not show the organization and clarity I would have expected. Each of you might ask yourself, 'Would I want to send this exam to my parents to show them the great work I'm doing at MIT?'"
He knew how to put the needle where we would feel it. But a B is a B and I'm here for another three months minimum.
The institute is laid back in the summertime. Because the undergrads are away, the nervous energy level is reduced by several orders of magnitude. You generally take only one course, and professors go on vacation. The MIT day camp is in session, and fresh young counselors lead large groups of little kids to the swimming pool and the gym.
