Observations from five stationary neutron monitors are used to demonstrate certain interesting effects in the 11-year modulation cycle of galactic cosmic rays. These effects are large-scale rigidity-dependent hysteresis structures, steplike modulation changes, and double minima in cosmic ray intensities over the modulation cycle. A technique is developed to interpret these effects in terms of the force field solution of the cosmic ray equation of streaming. It is found that all these effects can be explained in a spherical symmetric modulation model in which the cosmic ray diffusion coefficient is separable in rigidity-dependent and heliocentric-dependent parts. The results are then compared with those of other experiments, and general agreement is found between these experiments. This agreement indicates that the specific force field approach used here is valid. In the final section it is shown, however, that spherical symmetric modulation models, and consequently the force field approximation, may be oversimplifications of the true modulation mechanism. |