Hygroscopicity of Tree Barks

Experiments on the sorption of aqueous vapour by various barks at various humidities have been carried out for the first time. The results indicate that tree harks, with regard to sorption of water vapour, behave similar to wood. The maximum sorption at saturation humidity varies from 22%to 28%. Oven-drying does not reduce the sorption of water vapour by bark appreciably. The mechanism of sorption of vapours bv porous adsorbents is very briefly discussed. The importance of the data obtained to pharmacy and bark using indnstries is emphasized.