those bags you speak of - activated charcoal?? is there any sort of drip pan underneath those bags? if yes, those bags contain calcium chloride pellets which attracts moisture. if you go for a ride in the country where there are dirt roads, sometimes you see the road crews spreading white pellets on the ground. this is calcium chloride which pulls in the humidity from the air and it moistens the dirt to reduce dust from the ground. CaCL2 was used before commercial dehumidifiers were made.