Drifting Through Cozumel

Dear everybody,

Post number three comes to you from below sea level. I'm in Cozumel for the week, drifting along the reef the way the current intends - the local style of diving is exactly what it sounds like: you drop in, the Gulf does the swimming, and you steer about as much as a leaf in a river. After thirty-one years of project timelines, I find the entire concept restorative.

The diving

The reef here is part of the Mesoamerican system, the second-longest in the world, and it is absurdly alive. A few highlights from the logbook:

A note on the toadfish: they are endemic to this island, they live under ledges, and at night they hum so loudly you can feel it in your chest. The divemaster claims it's a love song. Nobody has corrected him.

Things I did not photograph because I was too busy grinning into my regulator:

• The spotted eagle rays, again, because four is not enough

• A lobster having what appeared to be a bad day

• My own bubbles, which at seventy feet look like quicksilver

Why diving keeps making the list

People ask why a man who spent his career in classrooms wants to spend retirement underwater, and the answer is that it's the same job: pay attention, stay curious, try not to touch anything. The reef does the teaching. I just show up with good buoyancy.

Next stop on the map: family reunion in September, and then - if the rumor mill is right - a certain band in a very round building in Las Vegas. More on that soon.

Yours, slightly salty,

• Tom