For several years some of the graduate students, under the supervision of Dr. Scherer, have been investigating the chemical, or physical, reactions which take place in xanthation of soda cellulose. Following the previous work carried out by Scherer, Miller (1), Lin (2), and others in determining the effect of various factors (i.e. effects of temperature and aging) on rate of xanthation, the purpose of this investigation was to determine the effect of bulk number, or degree of mechanical subdivision, on rate of xanthation. In studying this it was hoped to find additional information on the relation between structure of soda cellulose and its reactions with carbon disulfide. It is possible to eliminate the factor of mechanical subdivision from consideration of the rate of reaction between CS₂ and soda cellulose. The only apparent effect is that the denser material offers greater resistance to solution and in that way very slightly modifies the degree of xanthation owing to the necessity for a somewhat longer dispersion period with the resultant possibility of decomposition. The effect of bulk number variation on either rate of reaction, or distribution of the carbon disulfide, was well within the limit of experimental error and may be disregarded. / M.S.