The small hand on my watch sweeps around the watchface at twice the speed of the Earth’s rotation.
There’s a tiny window cut out of the watchface; it’s only a few millimeters across. It’s next to the “3” printed on the watchface. The numbers one through thirty-one are printed next to the outside edge of a wheel that turns behind the window. The numbers are just large enough for one of them to be seen through the window. The wheel remains stationary (relative to the rest of the watch) throughout most of the day. At the beginning of the last hour of the day it begins to turn. It continues to turn until the next number is completely visible through the window, at the end of the first of hour of the following day.
The number in the window corresponds to the day of the month. It goes out of sync five times a year, on the first day of each month that follows a month with fewer than thirty-one days. At some point, during the first few days after the number in the window goes out of sync, I’ll pull out the little knob on the side of the watch and reset the number in the window. I used to reset the number in the window by setting the watch forward twenty-four hours (eighty-six hours on March 1, 2001). But while resetting the watch on May 1, 2002, I discovered that if I only pulled the knob out half as far as it would go, I could set the number in the window without affecting the movement of the watch hands.
I also adjust the watch when I move between time zones. This is usually done on airplanes. I’m always careful to feign casualness, while at the same time making it clear to my seatmates what I’m doing. As if I was saying, “I have to do this so often that it’s second nature.” I think they usually see through my facade though.
I flew to Phoenix last spring. Arizona doesn’t adjust for daylight savings time, so Seattle time and Phoenix time where in sync and I didn’t adjust my watch. Daylight savings time ended while I was in Phoenix; so I only adjusted my watch on the flight back to Seattle.