Dosa, a mixture of animal glue and clum is used to size washi. Possible deterioration effects were examined. It was found that applying alum lowers paper ph, but if the paper is reasonably alkaline then the ph lowering is not too great; the greater the increase in acidity, the faster the rate of deterioration. The glue alone has little effect on the deterioration rate but does increase the tensile strength of the washi. Results are tabulated and illustrated graphically. References.