AbstractThe transport of aqueous urea, glucose, and sucrose through the cellulose membrane, Curophane, is described in terms of permeation and frictional coefficients. As for other cellulose materials, hydraulic flow for Cuprophane is predominantly of a capillary nature. While Cuprophane is relatively selective, reflecting more of these solutes than most other cellulose membranes, the observed flow rates through this very thin membrane are quite high. These permeation properties for Cuprophane are accommodated by the frictional description of membrane transport. The data are discussed and compared with other available data on related cellulose systems.