Atomic force microscopic (AFM) images of humic acids show discrete, globular particles, where particles of the order of magnitude 100 to 300 nm dominate the image fields; the humic acids had been grown to a steady state at pH 5.0. The AFM data are consistent with our previously reported small-angle neutron scattering (SANS) study done under similar conditions. In further agreement, the cluster-cluster interactions shown in our previous SANS study may have their counterparts in closely interacting particles appearing as twin particles in the AFM images