Abstract By the method of Smoluchowski, the spatial distribution of a fluctuation in magnetization has been calculated in two forms. For the first form, the magnetic moment and the external magnetic field are chosen as thennodynamic variables. For the second, the magnetic moment and the local magnetic field (which comprises both the external field and the Weiss molecular field) have been chosen. The correlation between spins has been related to these forms. The first choice of variables leads to a distribution of magnetic moment in the fluctuation which is described by the function (exp(k 1r)) r . With reference to the correlation between spins, it leads to the formula of van Hove. The second pair of variables leads to a distribution of magnetic moment described by the function (|sin k 2r|) r . The cross section for the magnetic scattering of neutrons at small angles, calculated with the correlation of this form, does not have a definite value unless one knows how to determine the range of correlation.