Insomnia has it right. I was trying to dry my first crop in a container with Damp Rid. After four days the shrooms were only partially dry. The Damp Rid had hardened over and didn't seem to be doing any work. After 24 hours in front of a fan the shrooms were reasonably dry; then I placed them back in the container with the Damp Rid. I checked back in two days and they were "cracker dry".

So the lesson I learned was not to depend on a chemical dessicant to get the ball rolling.