The origin of the so-called resonance disadvantage factor was investigated from the point of view of (1) the incomplete recovery of the flux at off-resonance energies and (2) the decrease in the surface flux due to the failure of the narrow resonance approximation in the moderator. The flux recovery was studied by age theory for a typical rectangular lattice of the uranium in graphite and the effect upon the absorption by the 6.7-ev resonance of U238 was found to be of the order of magnitude of 2% or less. The second problem was studied by solving for the space-energy flux by iteration. Sizeable corrections were found to be necessary for the low-lying resonances of U238 in graphite. An approximate analytical formula was presented for this correction.