[en] Presented are the results of measuring neutron spectra and their integral characteristics in a graphite-water system of cylindrical geometry in the milli eV range under the temperature gradient between praphite (500 K) and water (286 K). To measure the spectra the time-of-flight method was used. The neutron temperature was determined by the Wescott method. The experimental spectra and spatial distributions of the neutron temperature and fluence are compared with the results of calculations performed in terms of the P₁ approximation using the ''Demetra'' computer code for various models of neutron scattering in water. The anisotropy effects in the neutron flux are shown to be substantial for epithermal neutrons (0.01-0.2 eV) and for less pronounced for thermal neutrons, the effects of various scattering models being significantly less than the kinetic ones