With the political upheaval in the University of Illinois Physics department, David knew he would need to start looking for another job. Fortunately, interest in his work, stoked by media coverage especially in the New York Times, led to an offer from one of the top laboratories studying magnetism.
Named for a Massachusetts Institute of Technology (MIT) professor and pioneer in the production of intense magnetic fields, the Francis Bitter Magnet Laboratory at MIT was the world headquarters for basic magnetism research. “It was run by a man by the name of Benjamin Lax, a well-known solid-state physicist studying the basis of magnetism,” David says. “He liked my ideas so, when he heard I was in trouble, he arranged for me to come visit. I visited and gave a talk, and he made me an offer.”
At the time, MIT had two types of researchers: “soft money” faculty with no guarantee of funding and non-faculty with assured funding. Lax offered David a non-teaching position. “He said, ‘come to MIT and I’ll find you all the grant money you need and give you all the space you need,’” David recalls. “‘You will never be a professor at MIT, but you will have everything you will ever need to do research.’ Well, I grabbed this chance.”
“So I came to MIT,” he recalls. “My idea was to first build a shielded room which was effective enough to reduce the external magnetic field to below the level of the brain’s weak magnetic field. It had to be much better than my Illinois room.”
David had built the shielded room in Illinois alongside a carpenter named Carl Grundman. After he moved to MIT, he asked Grundman to come to Cambridge, Mass., to help him build a better shielded room there. The two worked well together. Also, because they had collaborated on the shielded room in Illinois, they could incorporate the lessons they had learned from that project. Helpfully, the University of Illinois allowed David to take materials from the now-deconstructed room on its campus, giving him a bit of a jump on his MIT room.
David designed the shielded room in about two months, then built it with Grundman and a handful of MIT carpenters and students. “Carl came out and he was my right-hand man,” David says. “There were about eight of us in all, and it took us six months to put the room together.”
The room was in the shape of a 26-sided sphere called a rhombicuboctahedron. “There are physics reasons why a sphere makes a very good magnetically shielded room, as opposed to a cube,” David says. “Twenty-six sides was just the engineering solution.” The room had three ferromagnetic layers with two layers of aluminum, with the latter joined together with silver plating. The MIT students were especially adept at completing the latter. “They were all engineering students and good at that sort of thing.”
David completed the shielded room in 1969—a pod-like structure with a stairway descending from an open panel on the side, it looked like something out of a science fiction movie—and started using it to measure the weak magnetic fields emanating from the human body. The room did an excellent job of keeping out any external magnetic fields—David estimates that it was ten times more effective than his shielded room in Illinois—but the copper coil-based detector he had developed was still noisy.
To address this problem, he turned to James Zimmerman, who had invented a superconducting quantum interference device (SQUID) several years before, when he was a researcher working with Ford Motor Co. (In those heady days, large corporations like AT&T and IBM as well as Ford were happy to maintain in-house labs conducting research with no obvious financial or commercial benefit to them.)
The introduction came by way of Ed Edelsack, a U.S. Navy funding officer who had recently awarded David a small grant. The Navy was also funding Zimmerman in his work and Edelsack suggested the two should meet. In a 2004 retrospective about his biomagnetism work in Boston, David described what happened next.
“Ed put me in touch with Jim, and it was arranged that Jim would bring one of his first SQUIDs to my lab at MIT, to look for biomagnetic signals in the shielded room. Jim arrived near the end of December, complete with SQUID, electronics, and nitrogen-shielded glass dewar. It took a few days to set up his system in the shielded room, and for Jim to tune the SQUID. Finally, we were ready to look at the easiest biomagnetic signal: the signal from the human heart, because it was large and regular. Jim stripped down to his shorts, and it was his heart that we first looked at.”
The results were nothing short of astounding; in terms of the signal measured, they were light years beyond anything David had seen with the copper coil-based detector. By combining the highly sensitive SQUID with the shielded room, which successfully eliminated outside magnetic disturbances, the two researchers were able to produce, for the first time, clear, unambiguous signals showing the magnetic fields produced by various organs of the human body. The implications of this were far reaching, with potential for a wide range of both basic science and clinical applications. David didn’t quite realize this at the time, but he and Zimmerman had just launched a new field of study, biomagnetism, one that would pay large dividends in terms of the potential benefits it could bestow.
Having demonstrated the efficacy of the new approach, which he had been thinking about and plotting for the better part of a decade, and which was rooted in his literally lifelong fascination with the principles of magnetism, David switched off the lights in the lab and he and Zimmerman went out to celebrate. It was December 31, 1969. The thrill of possibility hung in the air as they joined other revelers to ring in a new decade—indeed, a new era.
Where did they go? “I think I took him to a few New Year’s Eve parties,” David says. A few? “Well, you know, Cambridge is a swinging place.”
The answer prompts another question. A rhetorical question, perhaps, but one that still bears asking, especially given the decades of seeking, striving, learning and living that had made him who he was at that moment: a kid from the streets of Winnipeg who, through hard work and singular determination, had earned a place in academic research and turned an idea that many had dismissed as pure fancy into a reality, a reality that would have a significant impact in the years and decades to come.
Q: So it was a pretty good day, overall?
David responds with a hearty laugh. “Yes,” he says. “A very good day.”
