Abstract: An apparatus for tanning or dyeing includes a horizontal rotary drum which is rotatably mounted in a frame at only one axle front end thereof. The rotary drum defines a treatment chamber for tanning and dyeing which communicates with a hollow axle for admission and drainage of a liquid treatment medium. Within the interior of the rotary drum, at least two ring pocket sections are provided which are in communication with two connecting lines arranged at the axial front end of the rotary drum and extending in radial direction. With their radially external ends, each connecting line opens into the interior of the associated ring pocket section. The other end of each connecting line extends to the center of the rotary drum which center communicates with associated axial channels within the hollow axle.