Loss angle and dielectric constant of various celluloses were measured at frequencies of 500, 1000, 2000, and 4000 cycles by means of a conjugate Schering bridge equipped with a Wagner ground. A transition type oscillator was the source of variable frequency. The test capacitor system permitted measurement of electrode separation at the time of electrical measurement. The system could be evacuated to 0,1 micron pressure, and was enclosed in an insulated shielded box whose temperature could be controlled from 25 to 105°C. Dielectric constant was calculated to a standard density of 0.8 g/c.c, by means of the Clausius-Mosotti relation, Loss angle was calculated to standard density assuming that loss factor and density bear a linear relationship.