Limiting currents were measured for deposition of copper on plane vertical cathodes from unstirred solutions. Electrolyte composition ranged from 0.01 to 0.7 molal , 1.38 to 1.57 molal , and 0 to 6.38 molal glycerol. Cathode heights varied from 0.25 to 3.0 in. Limiting current densities were from 0.4 to 108 ma/cm2. A general correlation of the data may be represented by the equation: are the mass transfer Nusselt, Schmidt, and Grashof numbers, respectively. This result is in good agreement with that predicted from the boundary layer theory for mass transfer by free convection.