The subjects of this proposal, Ho2+xTi2-xO7-x/2, are brand new materials1 related to Ho2Ti2O7, a spin ice2,3. They have the remarkable property of remaining disordered at very low temperature and in strong applied fields. A strong quasi-elastic signal has been observed in Ho2+xTi2-xO7-x/2 which does not exist in the parent compound. We propose to characterize its temperature dependence to establish if it is of structural or magnetic origin. This will provide us with important information about the possible modification of the Ising like magnetic moments which are of central importance in the spin ice properties of a spin ice.