The purpose of this brief report is to determine the modification of equatorial waves of an ocean or atmosphere by the imposition of two infinite zonal walls. The region of interest lies within 30 ¿S to 30 ¿N. The geometry of two infinite zonal walls is relevant to numerical models in which walls are introduced along circles of latitude and possibly to the Caroline Basin (in the western Pacific). The numerical calculations agree with analytic solutions in the asymptotic limit.