Cellulose is hydrolyzed by water at temperatures over 100 C. at a rate which depends on the hydrogen ion concentration, even in the range between pH 5 and 8. Since acids are produced form the cellulose at higher temperatures, the pH of the aqueous medium tends to drop. Therefore, the effect of water on any sample of cellulose is determined by the pH and by the amount of buffering material present to prevent or retard the drop. The solubility of the degraded cellulose in water is highly dependent on the pH. The solubility is high above pH 7, and therefore, although a considerable amount of cellulose dissolved at higher temperatures, the alpha-cellulose dissolved at higher temperatures, the alpha-cellulose content of the residue remained high, probably due to solution of the beta-cellulose formed. Below pH 7 the solubility is low, and therefore as alpha-cellulose decreased due to hydrolytic degradation the beta - cellulose formed remained in the solid residue. -- CCI