There are many kinds of tanks. Think tanks hold scholars who concoct ideologies; armored tanks hold soldiers who enforce them. Some tanks we fail to remember, like the Zion-born crew mate from The Matrix, and some we try to forget, like the armless top often confused for appropriate wear.
As a verb, “tank” can impart as much damage as the shell-carrying noun. “The production tanked.” If tank had a sound, it would be the sound of a sledge in the side of a water tower and the subsequent liberated insides, falling to Earth.
Another meaning of tank is found a few blocks away from my home, under the banner of sensory deprivation. Also known as isolation tanks, they are the invention of John Lilly, a neuropsychiatrist.
My local offers four sensory deprivation tanks each the size of a Yugo. Each contains a mix of body temperature water, salt, and blackness. The goal is to lie atop the water and below the darkness, held in place by a metric ton of dissolved salt.
At first, you might not believe you can lie on water like a mattress. Your neck will try to support your bobbing head, but there’s no need to strain. Floating is the default state. Drowning is near impossible.
Eventually your body relents, but minds need more convincing. After my body relaxes, my mind chatters for a while, pinging the darkness for meaning. Eventually your internal monologue slows to a sputter. Your thoughts untether and your brain can join your body in a liquid state.
This tank is the only effective hiding spot from my unresting mind. In the dark, my mind unmoors from time and place. In the absence of light, I am illuminated.