An experimental investigation of the fluid dynamic forces on spheres suspended in a Poiseuille flow was performed. Small spheres of polystyrene, nylon, and lucite, having diameters ranging from 0.0610 inches to 0.1257 inches were suspended in Poiseuille flows in a 0.419 inch diameter tube. Variations in particle size and density, the fluid properties, and the angle of inclination of the tube, resulted in a sphere Reynolds number (based on particle diameter and approach velocity) ranging from 80 to 250. The results are presented as curves which include the coefficients of lift and drag plotted versus Reynolds number and a dimensionless shear parameter. Existing theory and experiment are carefully reviewed and compared with the experimental results. It was found that results valid in the Stokes regime cannot be successfully extrapolated into the higher Reynolds number range investigated. New qualitative relationships are suggested: (1) that the drag of a displaced sphere is the sum of centerline and displacement effects, and (2) that the lift has a square dependency upon the shear. (Author).