S. M. Cox1 has considered the departure from the ‘Maxwellian' law of the annealing-rate in glass. He attributes that part of the discrepancy which cannot be accounted for on the basis of a progressively changing viscosity to changes in the equilibrium condition of the glass under the action of the stresses present. An expression for the rate of release of stress is obtained, based on a theoretical derivation of the laws governing these changes and the rate of approach to equilibrium. Unfortunately, in his brief account only the final expression is given, so that it is not possible to comment on the derivation, nor on the extent to which a fit with Morey‘s experimental results provides a confirmation of the theory.