The present invention related generally to a device for adding moisture to fibrous material such as cotton. The conditioning device receives a continuous cotton batt from a battery condenser. The continuous cotton batt is fed between two opposing drums. Hot moist air is fed into one drum and drawn out of the perforated surface of the drum, through the batt as it is being compressed between the two drums, and into the other drum. The opposing drums are internally compartmented by a plurality of longitudinal staves, each compartment being covered by a corresponding segment of the perforated surface. Hot dry air is fed into the compartments of the drums when the corresponding segment of the surface is not carrying the cotton batt in order to dry the surface of the drum and clear the perforations of any lint that might have been retained on the surface.