The Stokes drag coefficients for conglomerates of between two and 167 spheres are obtained from a recently developed scheme for numerical calculations of hydrodynamic interactions [J. Chem. Phys. 100, 3780 (1994)]. Experimental data for these conglomerates were provided by Lasso and Weidmann [Phys. Fluids 29, 3921 (1986)]. The numerical results and the experimental data agree very well. It is shown that in numerical calculations of hydrodynamic interactions, all long-range contributions must be included exactly.