Originaly the sweatbox was a torture chamber. As of late every thing from greenhouses to plastic bags are called sweatboxes.

John

i read a website where a cardboard box with the top cut off and they used the aluminum foil and the shiny side out on the outside of the cardboard box and put plastic on the outside to makesure it didn't get wet. that was their sweat box, also they lined the inside of the box with a trash bag so as to not ruin the box when they watered the plants. it was interesting. it was also a mini greenhouse. LOL

OK, I get it; a sweatbox is an enclosed thingie to start plants, maintaining moisture.
Thanks,
LU