I note the time down on my arm with the pen—I haven’t found any paper yet.

I put the test tube back and repeat the test. This time I get 0.33. I do it twenty times total, noting the results, to minimize the effects of my error margin in starting and stopping the timer. Anyway, I end up with an average of 0.348 seconds. My arm looks like a math teacher’s chalkboard, but that’s okay.

0.348 seconds. Distance equals one-half acceleration times time squared. So acceleration equals two times distance over time squared. These formulas come easily to me. Second nature. I’m definitely skilled at physics. Good to know.

I run the numbers and come up with an answer I don’t like. The gravity in this room is too high. It’s 15 meters per second per second when it should be 9.8. That’s why things falling “feel” wrong to me. They’re falling too fast. And that’s why I’m so weak despite these muscles. Everything weighs one and a half times as much as it should.

Thing is, nothing affects gravity. You can’t increase or decrease it. Earth’s gravity is 9.8 meters per second per second. Period. And I’m experiencing more than that. There’s only one possible explanation.

I’m not on Earth.

Okay, take a breath. Let’s not jump to wild conclusions. Yes, the gravity is too high. Work from there and think of sensible answers.

I could be in a centrifuge. It would have to be pretty big. But with Earth’s gravity providing 1 g, you could have these rooms at an angle running around a track or on the end of a long solid arm or something. Set that spinning and the aggregate centripetal force plus Earth’s gravity could be 15 meters per second per second.

Why would someone make a huge centrifuge with hospital beds and a lab in it? I don’t know. Would it even be possible? How big would that radius have to be? And how fast would it go?

I think I know how to find out. I need an accurate accelerometer. Dropping things off a table and timing them is all well and fine for rough estimates, but it’s only as accurate as my reaction time on hitting the stopwatch. I need something better. And only one thing will do the job: a small piece of string.

I search the lab drawers.

After a few minutes, I have half the drawers open and have found just about every form of lab supplies except string. I’m about to give up when I finally find a spool of nylon thread.

“Yes!” I pull off a few feet of thread and cut it with my teeth. I tie a loop on one end and tie the other end around the tape measure. The tape measure will be playing the role of “dead weight” in this experiment. Now I just need something to hang it from.

I look above me at the hatch over my head. I climb up the ladder (easier now than ever before) and put the loop over the main latch handle. Then I let the tape measure’s weight pull the string taut.