Abstract : The heat exchange at the surface of a globe thermometer in equilibrium with its environment is described. A semitheoretical formula is derived, and presented graphically, to relate the diameter and emissivity of a globe to the environmental heat exchange of the particular animal species for which the globe is an analogue. Experimental data are presented which substantiate the validity of the formula. Published heat exchange data pertinent to humans are examined and the ratio of the parameter of convective heat exchange to the parameter of radiative heat exchange is determined for specified postures and directions of air movement. The values of diameter and emissivity in the globe thermometer providing the best analogue of man in these conditions are determined from this ratio. (Author)