One of the great joys of doing exactly the same thing every day is that you get to be comfortably familiar with regular occurrences, and more attuned to the things that change. Right now, patches of snow notwithstanding, spring is on its way, and it is starting to get light just before the end of second period in the morning. I am also starting to hear birdsong during the morning sitting. I leave it to someone more versed in the local fauna to identify the bird in question - my usual excuse for my ignorance in these matters is that this is not my bio-region, and where I come from we don't have such specimens, or they look different, like robins, and oak trees. Anyway, I know that these birds nest around Page Street, so it is nice to hear them again, alongside the more familiar sounds.
There are always the waves of traffic coming down the hill on Oak Street, streaming through the green lights, subsiding into quietness when the lights change further west. Usually, right after I arrive in the zendo, I hear a Harley-type motorbike which makes its presence felt with a little twist of the throttle as it cruises down across Laguna Street. There is someone who lives on Lily Alley who gets in their car to go to work at six ten, just as we settle down to second period, and on Tuesday mornings, there is the Green Gulch truck, the rear sliding door clanking shut after the compost buckets are loaded. When there is fog in the Golden Gate, we can hear the deep harmonies of the foghorns on the bridge. Even in the busier soundscape of evening zazen, I measure the progress of the period by hearing church bells striking six o'clock.