Consider a paramagnetic salt with a Debye temperature (Chapter) of 100K. A magnetic field of 100kG or 10tesla is available in the laboratory Estimate the temperature to which the salt must be pre-cooled by other means in order that significant magnetic cooling may subsequently be obtained by the isentropic demagnetization process. Take the magnetic moment of a paramagnetic ion to be 1 Bohr magneton. By significant cooling we may understand cooling to 0.1 of the initial temperature.