The present measurements comprise values of mean velocity and the mass concentration of a tracer in the flow downstream of a row of jets issuing normally into a free stream. The geometric configuration and velocity ratio are directly relevant to the combustion chamber of a gas turbine and the results were obtained to quantify the influence of asymmetry in the hole arrangement, on the down-stream mean-flow properties. The quantification of the influence of nonuniform pitch is of direct practical relevance and, also, is important to the development of methods for the determination of combustor performance by the solution of appropriate three-dimensional equations. A complete specification of a flow pattern, for calculation purposes, requires knowledge of boundary conditions and it is normally presumed that flow symmetry exists and corresponds to geometric symmetry. This assumption is imposed in the absence of experimental confirmation but, because of limitations of computer storage and run time, is probably essential at the present time.