I am diving inside a wrecked ship. My torch the only illumination. Passage
is frequently blocked by debris. Superstructures are so festooned with anemone
and seaweed, their function is unrecognizable. Microbial colonies at work
oxidizing iron form delicate fingers of rust, dissolving at the slightest
touch. The ship has been down here a long time.

If you go deep enough in the ocean, it is easy to become disoriented, unable
to discern the difference between up and down. Disorientation while diving can
be perilous. I once dove with someone who, already narcoleptic at that depth,
dropped her flashlight and headed toward it, convinced she needed to go toward
its light.

Since the deeper we go, the more frequent and longer the decompression stops
on the way back up must be, she ran the risk of running out of air. These
decompression stops – which allow for the elimination of dissolved gases from
the body – are critical. Decompress too quickly and the excess nitrogen can be
painful…or lethal.

I have been here before but with the passing of time the landscape has
altered. The ship has shifted, settled. The silt is deeper. I am no longer sure
of my way. I release a few air bubbles. They rise topside, showing me the way
up and out. Because my explorations took me so deep, I will need several
decompression stops. To the uninitiated, it may look as if I am reluctant to
leave my watery environment.

But I am following the small silver balls of oxygen. Keeping an eye on my scuba
tank gauges and taking whatever time is needed to adjust to the changes in
pressure, I float toward the light of the sun.