MIT undergraduate germanium thermometer superconductivity calibration

As an MIT undergraduate working in a superconductivity lab attempting to break the (then ~20.3 K) world record, Tom's group owned a single $500 germanium thermometer. Buying a second one to hedge against failure produced six months of confusion because the two thermometers disagreed by a couple of tenths of a degree near liquid helium — and they could not determine which was correct. Used as a personal illustration that adding a second measurement can destroy confidence rather than build it.

When I was an undergraduate student working in the lab around here, we were doing superconductivity. We only owned one germanium thermometer. They cost $500, which was a lot of money back then. We decided, well, if that one breaks, we're going to be out of business — we need to buy another one. We spent six months trying to figure out which one was correct. Because you put them both down in liquid helium and start heating things up, and they're off by a couple of tenths of a degree. So which one's right? We knew what the temperature was when we only had one measurement. We had two measurements now, and we didn't have a clue. I was trying to measure 18.1 degrees versus 18.2 degrees, for which one's the better superconductor. We were trying to break the world's record. At that time it was 20.3 or something.