Sensory deprivation tanks are fantastic! Inside of the pitch-black float tanks is a water and salt solution kept at a temperature comparable to external body heat. These conditions create a sense of calmness and can relieve pain. What this also provides is optimal conditions for out of body experiences if one chooses to go that route.
The first float tank was created by the neuropsychologist, Dr. John C. Lilly at the National Institute for Mental Health in 1954. He was obsessed with consciousness. His directive was to explore altered states and internal space. On his website http://johnclilly.com/ it quotes at the top "In the province of the mind, there are no limits." And he's right.
My first experience was a 60-minute float, which in hindsight, I should have paid for the 90 minutes. The float started slow. I didn't know what to expect, and I had to get over the idea that I was in this tank, naked, that other people lay naked in as well. The water is cleaned regularly and highly filtered between each float. Then I had to mess around with the fact that I could see that same thing whether my eyes were open or closed. Once I got over my silly thoughts, the disconnect from the body began to take hold. It was calm. I was relaxed.
I feel like someone who has had practice with meditation or breathwork may have a better idea of what to do inside of the tank. I only say that because while I was in a meditative state, I began to let go. In doing so, a beautiful internal design began to take form. I was at my grandparent's old farmhouse that I can vaguely remember from my childhood. Everything was very distinguishable but encompassed with a beautiful purple hue. There wasn't any specific actions that were entertaining; I was only sitting under a tree eating a pear. The image and where it came from was enough to have me in a state of wonder. Everything made of different purple colors was beautiful. It was every shade of purple unimaginable. I hadn't thought about that house in many years. What happened, was I exploring my subconscious? Was I reliving a childhood experience that I had once forgotten? Did I tap into a parallel universe and view a different version of myself experiencing myself? Just as this exploration was starting to seem extremely interesting, I heard a voice in my head come out with "show me what you got, loverboy." Immediately after the loverboy comment, the music came over the speakers in the pod signaling my time was up.
The float experience was great. I felt refreshed, calm, and repaired. My skin was as soft as a baby's skin for about four days. If someone is interested in the idea of float tanks, then I highly suggest they explore their curiosity. They won't be disappointed.
Is sensory deprivation the lost clue to what the sarcophagi were used for in Giza? There haven't been any mummies found in the pyramids there, were they using these for sensory deprivation?